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otter	What is the primary item in an otter's diet?	Fish.	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	What is the primary item in an otter's diet?	fish	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	What is an otter's den called?	Holt	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	What is an otter's den called?	holt	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Why is the giant otter becoming increasingly rare?	Poaching, habitat loss, and toxins in gold mining.	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Why is the giant otter becoming increasingly rare?	poaching, habitat loss, and the use of mercury in illegal alluvial gold mining	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	How do otters keep themselves warm without blubber?	A layer of air trapped in their fur.	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	How do otters keep themselves warm without blubber?	a layer of air trapped in their fur	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	How are otters playful animals?	The slide down snowy slopes, apparently for sheer enjoyment.	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	How are otters playful animals?	They slide repeatedly down snowy slopes for sheer enjoyment.	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	What animals are related to otters?	weasels, polecats, and badgers	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	What traps a layer of air, and keeps them dry and warm under water?	Long guard hair	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	The collective noun romp is sometimes used for a group of what?	Otters	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Is it true that otters eat a variety of fish?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Are otters playful animals?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Are otters very active?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Are male otters dog-otters?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	An otter 's den is what?	A holt	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Sea otters eat what?	Shellfish and other invertebrates	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Is the myth of Otter 's Ransom the starting point of the Volsunga saga ?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Are Male otters dog-otters , females are bitches and babies are cubs or pups ?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Is an otter 's den called a holt ?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
otter	Have most otters fish as the primary item in their diet , supplemented by frogs , crayfish and crabs ?	yes	data/set1/a7	otter Otters are amphibious (or in one case aquatic) carnivorous mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, as well as others. With 13 species in 7 genera, otters have an almost worldwide distribution. An otter's den is called a holt. Male otters are dog-otters, females are bitches and babies are cubs or pups. The collective noun romp is sometimes used for a group of otters, being descriptive of their often playful nature. Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all but the sea otter have long muscular tails. They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water. Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high metabolic rates. For example Eurasian otters must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10Â°C an otter needs to catch 100 g of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day. Most otters have fish as the primary item in their diet, supplemented by frogs, crayfish and crabs. Some are expert at opening shellfish, and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion. Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter lives actually in the sea. Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups in a few species these groups may be fairly large. The following are short descriptions of a selection of species (see below for full list) The northern river otter (Lontra canadensis) became one of the major animals hunted and trapped for fur in North America after European contact. As one of the most playful, curious, and active species of otter, they have become a popular exhibit in zoos and aquaria, but unwelcome on agricultural land because they alter river banks for access, sliding, and defense . River otters eat a variety of fish and shellfish, as well as small land mammals and birds. They grow to 1 m (3 to 4 feet) in length and weigh from 5 to 15 kg (10 to 30 pounds). In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover. A sea otter in Morro Bay, California Sea otters (Enhydra lutris) live along the Pacific coast of North America. Their historic range included shallow waters of the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have some 200,000 hairs per square cm of skin, a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable. Sea otters eat shellfish and other invertebrates (especially clams, abalone, and sea urchins ), frequently using rocks as crude tools to smash open shells. They grow to 1 to 1.5 m (2.5 to 5 feet) in length and weigh 30 kg (about 65 pounds). Although once near extinction, they have begun to spread again, from remnant populations in California and Alaska. Unlike most marine mammals such as (seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land. This sub-species (Lutrogale perspicillata maxwelli) of the smooth-coated otter was the subject of the book Ring of Bright Water by the British naturalist Gavin Maxwell, and is named after him. It is native to the Tigris-Euphrates alluvial salt marsh of Iraq, but it has been suggested that it may have become extinct as a result of the large-scale drainage that has taken place in the region since the 1960s . Eurasian otter This species (Lutra lutra) inhabits Europe, and its range also extends across most of Asia and parts of North Africa. In the British Isles they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of chlorinated hydrocarbon pesticides and as a result of habitat-loss and water pollution (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly, and by 1999 estimated numbers indicated a recovery to under 1000 animals . The UK Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. Roadkill deaths have become one of the significant threats to the success of their re-establishment. The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 feet), and is more aquatic than most other otters. The word "otter" derives from the Old English word otr, otor or oter. This and cognate words in other Indo-European languages ultimately stem from a root which also gave rise to the English words "water", "wet" and "winter". Norse mythology tells of the dwarf Ãtr habitually taking the form of an otter. The myth of Otter's Ransom is the starting point of the Volsunga saga. In some Native American cultures, otters are considered totem animals. The time of year associated with this is also associated with the Aquarius sign of the Zodiac, through which the sun passes January 20-February 19. An otter in Southwold, Suffolk, England Genus Lutra Eurasian otter (Lutra lutra) Hairy-nosed otter (Lutra sumatrana) Lutra bravardi Lutra libyca Lutra palaeindica Lutra simplicidens Genus Hydrictis Speckle-throated otter (Hydrictis maculicollis) Genus Lutrogale Smooth-coated otter (Lutrogale perspicillata) Genus Lontra Northern river otter (Lontra canadensis) Southern river otter (Lontra provocax) Neotropical river otter (Lontra longicaudis) Marine otter (Lontra felina) Genus Pteronura Giant otter (Pteronura brasiliensis) Genus Aonyx African clawless otter (Aonyx capensis) Congo clawless otter (Aonyx congicus) Oriental small-clawed otter (Aonyx cinereus) Genus Enhydra Sea otter (Enhydra lutris) Image:Amblonyx_cinereus.jpg\| Oriental small-clawed otter Image:giantotter.jpg\|Giant otter Image:Lutra_longicaudis.jpg\|Long-tailed otter in Tortuguero, Costa Rica Image:Otters.jpg\|otters at the Perth Zoo, Western Australia See for an explanation of how to generate footnotes using the and tags, and the template below. --> } Gallant, D., L. Vasseur, & C.H. BÃ©rubÃ© (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. Journal of Wildlife Management 71:258â265. * The Somerset Otter Group * The Otter Trust * International Otter Survival Fund * Otternet * North American River Otter Related Wikipedia Articles Northern river otter Animal Chordata Mammal Carnivora Mustelidae Amblonyx Aonyx Enhydra Lontra Lutra Lutrogale Pteronura amphibious aquatic animal carnivore mammal Rank (zoology) Family (biology) Mustelidae weasel polecat badger species genus holt collective noun sea otter metabolic rate Eurasian otter sea otter fish frog crayfish crab shellfish sea otter #List of species fur bird foot (length) pound (mass) Morro Bay Pacific Bering Strait Kamchatka Peninsula hair skin invertebrate clam abalone sea urchin tool Animal shell California Alaska Pinniped whale blubber smooth-coated otter Ring of Bright Water Gavin Maxwell Tigris-Euphrates alluvial salt marsh Iraq Asia North Africa British Isles chlorinated hydrocarbon pesticide Habitat (ecology) pollution Scotland Ireland animals Biodiversity Action Plan Roadkill giant otter Old English language Indo-European languages root (linguistics) Norse mythology Norse dwarves Ãtr Volsunga saga totem animals Aquarius (astrology) Zodiac Southwold Suffolk England Lutra Eurasian otter Hairy-nosed otter Hydrictis Speckle-throated otter Lutrogale Smooth-coated otter Lontra Northern river otter Southern river otter Neotropical river otter Marine otter Pteronura Giant otter Aonyx African clawless otter Congo clawless otter Oriental small-clawed otter Enhydra Sea otter
penguin	Do penguins feed on krill?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Do penguins feed on krill?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is the largest living species of penguin?	Emperor Penguin	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is the largest living species of penguin?	the Emperor Penguin (Aptenodytes forsteri)	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Do penguins live almost exclusively in the Southern Hemisphere?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Do penguins live almost exclusively in the Southern Hemisphere?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is "tobogganing"?	when penguins slide on their bellies across the snow	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is "tobogganing"?	Tobogganing is when penguins slide on their bellies across the snow.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Why are penguins countershaded?	for camouflage	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Why are penguins countershaded?	for camouflage	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins afraid of humans?	no	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins afraid of humans?	no	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How much time to penguins spend on land?	half of their life	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How much time to penguins spend on land?	They spend half of their life on land.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How many species of penguins are there?	between 17 and 20 living species	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How many species of penguins are there?	Penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How are Isabelline penguins different from most penguins?	they have brown rather than black plumage	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How are Isabelline penguins different from most penguins?	Because they are born with brown rather than black plumage.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins birds?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins birds?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Do penguins have a better than average sense of hearing for birds?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Do penguins have a better than average sense of hearing for birds?	No	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins considered "higher waterbirds"?	yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins considered "higher waterbirds"?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What order do penguins belong to?	Sphenisciformes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What order do penguins belong to?	Sphenisciformes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is the largest living species of penguin?	Emperor Penguin	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is the largest living species of penguin?	Emperor	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How tall were the tallest prehistoric penguins?	1.80 meters	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	How tall were the tallest prehistoric penguins?	as tall as an adult human	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What makes penguins so agile in the water?	Their wings have become flippers	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What makes penguins so agile in the water?	Smooth plumage preserves a layer of air, ensuring buoyancy, wings are flippers	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Why do penguins "tobaggan"?	It conserves energy while moving quickly	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Why do penguins "tobaggan"?	Conserves energy while moving quickly	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Who spend half of their life on land and half in the oceans?	Penguins	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What is also the distance that Antarctic tourists are told to keep from penguins?	3 meters	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What have become flippers, useless for flight in the air?	Penguins' wings	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What happens when mothers lose a chick?	They sometimes attempt to "steal" another chick.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is it true that each penguin gets a turn in the center?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are all penguins countershaded?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins astonishingly agile?	In the water they are.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Are penguins at risk?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is it also possible that penguin comes from the Latin pinguis , fat ?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Have penguins an average sense of hearing for birds ?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Can larger penguins dive deep in case of need ?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is the smallest penguin species the Little Blue Penguin -LRB- also known as the Fairy Penguin -RRB- , which stands around 40 cm tall -LRB- 16 in -RRB- and weighs 1 kg -LRB- 2.2 lb -RRB- ?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is it not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage , or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae ?	It is not even known.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is the largest living species the emperor penguin -LRB- aptenodytes forsteri -RRB-?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	Is the smallest penguin species the little blue penguin -LRB- also known as the fairy penguin -RRB- , which stands around 40 cm tall -LRB- 16 in -RRB- and weighs 1 kg -LRB- 2?	Yes	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
penguin	What happened in a region not quite 2000 km south of the equator 35 mya?	At least one giant penguin.	data/set1/a3	penguin A penguin encounters a human during Antarctic summer. Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the Southern Hemisphere. The number of penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin (e.g. Williams, 1995; Davis & Renner, 2003); the actual situation seems to be more complicated (Banks et al. 2002). Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. Also eligible to be a separate species is the Northern population of Rockhopper penguins (Davis & Renner, 2003). Although all penguin species are native to the southern hemisphere, they are not, contrary to popular belief, found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. At least ten species live in the temperate zone; one lives as far north as the GalÃ¡pagos Islands: the GalÃ¡pagos Penguin. The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2000 km south of the Equator 35 mya , in a climate decidedy warmer than today. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend half of their life on land and half in the oceans. Penguins seem to have no special fear of humans and have approached groups of explorers without hesitation. This is probably on account of there being no land predators in Antarctica or the nearby offshore islands that prey on or attack penguins. Instead, penguins are at risk at sea from predators such as the leopard seal. Typically, penguins do not approach closer than about 3 meters (9 ft); they become nervous at about that distance. This is also the distance that Antarctic tourists are told to keep from penguins (tourists are not supposed to approach closer than 3 meters, but are not expected to withdraw if the penguins come closer). 250px Penguins are superbly adapted to an aquatic life. Their wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded - that is, they have a white underside and a dark (mostly black) upperside. This is for camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach 6 to 12 km/h (3.7 to 7.5 mph), though there are reports of velocities of 27 km/h (17 mph) (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep in case of need. Dives of the large Emperor Penguin have been recorded which reach a depth of 565 m (1870 ft) and last up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds (Wever et al 1969); this is used by parents and chicks to locate one another in crowded colonies (Jouventin et al 1999). Their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis (Sivak et al 1987). Penguins have a thick layer of insulating feathers which are designed to keep them warm in water (heat loss in water is much greater than in air). The Emperor penguin (the largest penguin) has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood which gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that each penguin gets a turn in the center of the heat pack. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. Some penguins mate for life, others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and the young. During the cold season on the other hand the mates separate for several months to protect the egg. Usually, the male stays with the egg and keeps it warm while the female goes to sea to find food for the baby. When the female comes back, they switch roles. When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crÃ¨ches . Isabelline AdÃ©lie penguin on Gourdin Island, December 2002 Perhaps one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called Isabelline penguins, possibly in reference to the legend that the archduchess Isabella of Austria vowed not to change her undergarments until her husband united the northern and southern Low Countries by taking the city of Ostend--which took three years to accomplish. Isabellinism is different from albinism, though the faded color of the plumage calls albinism to mind. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well camouflaged against the deep, and are often passed over as mates. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006). See the gallery for images of most living species. ORDER SPHENISCIFORMES Basal and unresolved taxa (all fossil) * Waimanu - basal (Middle-Late Paleocene) Perudyptes (Middle Eocene of Atacama Desert, Peru) - basal? Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina: Clarke et al. 2003) Delphinornis (Middle/Late Eocene ?- Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Archaeospheniscus (Middle/Late Eocene - Late Oligocene) - Palaeeudyptinae? New subfamily 2? Marambiornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Mesetaornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) - Palaeeudyptinae, basal, new subfamily 1? Tonniornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Wimanornis (Late Eocene -? Early Oligocene of Seymour Island, Antarctica) Duntroonornis (Late Oligocene of Otago, New Zealand) - possibly Spheniscinae Korora (bird) (Late Oligocene of S Canterbury, New Zealand) Platydyptes (Late Oligocene of New Zealand) - possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily? ''Spheniscus gen. et sp. indet (Late Oligocene/Early Miocene of Hakataramea, New Zealand) Madrynornis (Puerto Madryn Late Miocene of Argentina) - possibly Spheniscinae Pseudaptenodytes (Late Miocene/Early Pliocene) Dege (penguin) (Early Pliocene of South Africa) - possibly Spheniscinae Marplesornis (Early Pliocene) - possibly Spheniscinae Nucleornis (Early Pliocene of Duinfontain, South Africa) - possibly Spheniscinae Inguza (Late Pliocene) - probably Spheniscinae; formerly Spheniscus predemersus * Family Spheniscidae Subfamily Palaeeudyptinae - Giant penguins (fossil) * Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily * Anthropornis (Middle Eocene ?- Early Oligocene of Seymour Island, Antarctica) - tentatively assigned to this subfamily Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi * Icadyptes (Late Eocene of Atacama Desert, Peru) * Palaeeudyptes (Middle/Late Eocene - Late Oligocene) - polyphyletic; some belong in other subfamilies * Pachydyptes (Late Eocene) * Anthropodyptes (Middle Miocene) - tentatively assigned to this subfamily Subfamily Paraptenodytinae - Stout-legged penguins (fossil) * Arthrodytes (San Julian Late Eocene/Early Oligocene - Patagonia Early Miocene of Patagonia, Argentina) * Paraptenodytes (Early - Late Miocene/Early Pliocene) Subfamily Palaeospheniscinae - Slender-legged penguins (fossil) * Eretiscus (Patagonia Early Miocene of Patagonia, Argentina) * Palaeospheniscus (Early? - Late Miocene/Early Pliocene) - includes Chubutodyptes Subfamily Spheniscinae - Modern penguins * Aptenodytes - Great penguins (2 species) * Pygoscelis - Brush-tailed penguins (3 species) * Eudyptula - Little penguins (2 species) * Spheniscus - Banded penguins (4 species) * Megadyptes - Yellow-eyed Penguin * Eudyptes - Crested penguins (6-8 living species) Taxonomy: Clarke et al. (2003) and Ksepka et al. (2006) apply the phylogenetic taxon Spheniscidae what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish (Clarke et al. 2003) the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious and in any case is confusing; the established Linnean system is thus followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005 (Bertelli & Giannini 2005, Baker et al. 2006, Ksepka et al. 2006, Slack et al. 2006), the evolution of the living genera can be considered resolved by now. According to the comprehensive review of the available evidence by Ksepka et al. (2006), the basal penguins lived around the time of the CretaceousâTertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian-Maastrichtian boundary, around 70-68 mya (Baker et al. 2006, Slack et al. 2006) The exact divergence dates according to Baker et al. (2006) mentioned in this section are not as precisely resolved as it appears to be due to uncertainties of the molecular clock used. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs which follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant). The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya (Slack et al. 2006). While they were not as well adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were - as opposed to most other diving birds, living and extinct - already adapting to underwater locomotion. Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39-38 mya Contra Baker et al. (2006). , primitive penguins had spread to South America and were in the process of expanding into Atlantic waters (Clarke et al. 2003). During the Late Eocene and the Early Oligocene (40-30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least 2 major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other - which is or includes the paleeeudyptines as recognized today - occurred on most Antarctic and subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around ten known species of penguins ranging from medium to huge size apparently coexisted some 35 mya during the Priabonian (Late Eocene) (Jadwiszczak 2006). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae - were they considered valid -, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi) (Ksepka et al. 2006). The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya. In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Interestingly, their decline and disappearance coincides with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful (Baker et al. 2006). A new lineage, the Paraptenodytes which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation which gave rise to the penguin biodiversity of our time. Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships (Bertelli & Giannini 2005). The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic (Baker et al. 2006). Presumedly diverging from other penguins around 40 mya (Baker et al. 2006), it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution. The genus Aptenodytes appears to be the basalmost divergence among living penguins; they have bright yellow-orange neck, breast, and bill patches, incubate by placing their eggs on their feet, and when they hatch, they are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today. Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian In fact, it is fairly likely that during the Bartonian, there was a near-synchronous but allopatric split between the ancestors of Aptenodytes, Pygoscelis, and the common ancestor of all remaining genera (Baker et al. 2006). , but the range expansion and radiation which lead to the present-day diversity probably did not occur until much later, around the Burdigalian stage of the Early Miocene, roughly 20-15 mya (Baker et al. 2006). The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins in nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya (Baker et al. 2006). While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4-2 mya (Baker et al. 2006). The Megadyptes - Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15-14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene (Baker et al. 2006). It is most interesting to note that the geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record (Baker et al. 2006). The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond (Baker et al. 2006). Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14 to 12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond Waimanu remains unknown and not well resolved by molecular or morphological analyses. The latter tend to be confounded by the strong adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) which comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes (Fain & Houde 2004). Inside this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes (e.g. Slack et al. 2006) or to Procellariiformes (Baker et al. 2006) has been suggested. Some (e.g. Mayr 2005) think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. The Auk of the Northern Hemisphere is superficially similar to penguins, they are not related to the penguins at all, but considered by some to be a product of moderate convergent evolution Convergence and divergence in the evolution of aquatic birds by Marcel Van Tuinen, Dave Brian Butvill, John A. W. Kirsch and S. Blair Hedges The word Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), Oxford English Dictionary. Accessed March 21, 2007. applied to the Great Auk, which had white spots in front of its eyes (although its head was black), or from an island off Newfoundland known as Pengwyn, due to a large white rock. (In the latter case, the name may also have come from Breton.) This theory is supported by the fact that penguins look remarkably like Great Auks in general shape. It is also possible that penguin comes from the Latin pinguis, âfatâ. This is supported by the fact that the corresponding words in most other languages (e.g., French pingouin, German Pinguin) have i instead of e as the first vowel. However, a Welsh 'i' is often sound-shifted to an 'e' in the English language, . Another theory states that the word is an alteration of âpen-wingâ, with reference to the rudimentary wings of both Great Auks and penguins, but there is no evidence for this. Tux the Linux kernel mascot Penguins are popular around the world, primarily for their unusually upright, waddling pace and (compared to other birds) lack of fear of humans. Their striking black and white plumage is often likened to a tuxedo suit. Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. Penguins have also been the subject of many books and documentary films such as Happy Feet and Surf's Up, both CGI-Animated Animal Adventure Films, March of the Penguins, a documentary based on the migration process of Emperors, and a parody film entitled Farce of the Penguins. Mistakenly, some artists and writers have penguins based in the North Pole. This is incorrect as there are almost no wild penguins in the northern hemisphere, and those only barely (northernmost of the GalÃ¡pagos). Penguins have also found their way into a number of cartoons and television dramas, perhaps the most notable of these is Pingu - created by Silvio Mazzola in 1986 and covering more than 100 short episodes. Image:Emperor penguins.jpg\|Emperor Penguins Aptenodytes forsteri Image:Koenigspinguine.jpg\|King Penguins Aptenodytes patagonicus Image:Manchot 04.jpg\|Chinstrap Penguin Pygoscelis antarctica Image:Pygoscelis_papua.jpg\|Gentoo Penguin Pygoscelis papua Image:RoyalPenguins2.JPG\|Royal Penguin Eudyptes schlegeli Image:Eudyptes chrysocome.jpg\|Southern Rockhopper Penguin Eudyptes chrysocome Image:Fiordland penguin (Mattern).jpg\|Fiordland Penguin Eudyptes pachyrhynchus Image:SnaresPenguin (Mattern).jpg\|Snares Penguin Eudyptes robustus Image:Macaroni_penguin.jpg\|Macaroni Penguin Eudyptes chrysolophus Image:MegadyptesAntipodes.jpg\|Yellow-eyed Penguin Megadyptes antipodes Image:Little Penguin.jpg\|Little Penguin or Fairy Penguin Eudyptula minor Image:penguin.jackass.arp.500pix.jpg\|African Penguin or Jackass Penguin Spheniscus demersus Image:Spheniscus mendiculus.jpg\|Galapagos Penguins Spheniscus mendiculus Image:Humboldt Penguin.jpg\|Humboldt Penguin Spheniscus humboldti Image:Magellanic-penguin02.jpg\|Magellanic Penguin Spheniscus magellanicus Image:Adelie penguins at iceberg.jpg\|AdÃ©lie penguins Pygoscelis adeliae at iceberg in Ross Sea, Antarctica Image:Emperor chick with parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick) Image:Emperor penguin 2 chicks and a parent.jpg\|Emperor Penguins Aptenodytes forsteri (a parent with a chick and lonely chick behind) Image:Kaiserpinguinjunges.jpg\|Emperor Penguins Aptenodytes forsteri - a chick Image:Eudyptes chrysolophus at south georgia.jpg\|Macaroni penguin at South Georgia Island Image:Pygoscelis antarctica feeding a chick.jpg.jpg\|Chinstrap Penguin feeding a chick in Antarctica Image:Adelie chicks in antarctica and Ms Explorer.jpg\|AdÃ©lie chicks in Antarctica Image:Seal and king penguins.jpg\|Southern Elephant Seal and King Penguins * 2 new fossil penguin species found in Peru- * Acosta Hospitaleche, Carolina (2004): Los pingÃ¼inos (Aves, Sphenisciformes) fÃ³siles de Patagonia. SistemÃ¡tica, biogeografÃa y evoluciÃ³n. Doctoral thesis, Department of Natural Sciences and Museum, Universidad Nacional de La Plata. La Plata, Argentina. [in Spanish] PDF fulltext * Baker, Allan J.; Pereira, Sergio Luiz; Haddrath, Oliver P. & Edge, Kerri-Anne (2006): Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling. Proc. R. Soc. B 273: 11-17. PDF fulltext * Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29â38. PDF fulltext * Bertelli, Sara & Giannini, Norberto P. (2005): A phylogeny of extant penguins (Aves: Sphenisciformes) combining morphology and mitochondrial sequences. Cladistics 21(3): 209â239. (HTML abstract) * Clarke, Julia A.; Olivero, Eduardo B. & Puerta, Pablo (2003): Description of the earliest fossil penguin from South America and first Paleogene vertebrate locality of Tierra Del Fuego, Argentina. American Museum novitates 3423: 1-18. PDF fulltext * Davis; Lloyd S. & Renner; M. (1995). Penguins . London: T & A D Poyser. ISBN 0-7136-6550-5 * Fain, Matthew G. & Houde, Peter (2004): Parallel radiations in the primary clades of birds. Evolution 58(11): 2558-2573. PDF fulltext * Jadwiszczak, Piotr (2006): Eocene penguins of Seymour Island, Antarctica: taxonomy. Polish Polar Research 27(1), 3â62. PDF fulltext * Jouventin, P; Aubin, T. & T Lengagne (1999) "Finding a parent in a king penguin colony: the acoustic system of individual recognition" Animal Behaviour 57: 1175â1183 * Ksepka, Daniel T., Bertelli, Sara & Giannini, Norberto P. (2006): The phylogeny of the living and fossil Sphenisciformes (penguins). Cladistics 22(5): 412â441. (HTML abstract) * Marples, B. J. (1962): Observations on the history of penguins. In: Leeper, G. W. (ed.), The evolution of living organisms. Melbourne, Melbourne University Press: 408-416. * Mayr, G. (2005): Tertiary plotopterids (Aves, Plotopteridae) and a novel hypothesis on the phylogenetic relationships of penguins (Spheniscidae). Journal of Zoological Systematics and Evolutionary Research 43(1): 61-71. PDF fulltext * Sivak, J.; Howland, H. & McGill-Harelstad, P. (1987) "Vision of the Humboldt Penguin (Spheniscus humboldti) in Air and Water " Proceedings of the Royal Society of London. Series B, Biological Sciences. 229(1257): 467-472 * Slack, Kerryn E.; Jones, Craig M.; Ando, Tatsuro; Harrison G. L. "Abby"; Fordyce R. Ewan; Arnason, Ulfur & Penny, David (2006): Early Penguin Fossils, plus Mitochondrial Genomes, Calibrate Avian Evolution. Molecular Biology and Evolution 23(6): 1144-1155. PDF fulltext Supplementary Material Wever, E.; Herman, P.; Simmons, J. & Hertzler D (1969) "Hearing in the Blackfooted Penguin, Spheniscus demersus, as Represented by the Cochlear Potentials" PNAS 63(3): 676-680 Williams; Tony D. (1995). The Penguins - Spheniscidae . Oxford: Oxford University Press. ISBN 0-19-854667-X * Penguin World * penguinpage.net - Penguin research projects on the web * Penguin information on 70South * Information about penguins at pinguins.info * PBS Nature: The World of Penguins * Integrated Taxonomic Information System * Seaworld Penguin Information * Penguin Videos on the Internet Bird Collection Related Wikipedia Articles Paleocene Gentoo Penguin Animal Chordata Aves Richard Bowdler Sharpe Charles Lucien Jules Laurent Bonaparte genus Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus Sphenisciformes#Systematics human order (biology) family (biology) Aquatic animal flightless bird bird Southern Hemisphere species biodiversity subfamily White-flippered Penguin Eudyptula Little Penguin Royal Penguin Macaroni penguin Rockhopper Penguin Antarctica temperate GalÃ¡pagos Islands GalÃ¡pagos Penguin Emperor Penguin mass Little Penguin Bergmann's Rule prehistoric subantarctic Equator mya (unit) krill fish squid sealife Antarctica prey leopard seal Orca AdÃ©lie Ross Sea Antarctica Drygalski ice tongue wing plumage tail countershading camouflage orca leopard seal Emperor Penguin hearing (sense) seabird colony eye nearsighted supraorbital gland chick Emperor Penguin crÃ¨che (zoology) Isabella of Austria Penguin#Gallery of living species Basal (phylogenetics) fossil Waimanu Spheniscidae Archaeospheniscus Korora Spheniscus Pseudaptenodytes Inguza Palaeeudyptinae fossil Anthropornis nordenskjoeldi Anthropornis nordenskjoeldi Icadyptes Palaeeudyptes Pachydyptes Anthropodyptes fossil Paraptenodytes Palaeospheniscinae fossil Palaeospheniscus Aptenodytes Pygoscelis Eudyptula Spheniscus Megadyptes Eudyptes phylogenetic taxonomy Linnean taxonomy phylogeny evolution biogeography alpha taxonomy Basal (phylogenetics) CretaceousâTertiary extinction event New Zealand Byrd Land plate tectonics most recent common ancestor sister clade Campanian Maastrichtian molecular clock Cretaceous morphology (biology) trophic web Flightless Cormorant fossil Paleocene New Zealand mya (unit) Waimanu loon Argentina Bartonian Eocene South America Atlantic Oligocene Nordenskjoeld's Giant Penguin New Zealand Giant Penguin New Zealand paraphyletic subfamily Palaeeudyptinae phylogeny Patagonia Antarctic subantarctic adaptive radiation Seymour Island Priabonian monophyletic Anthropornis nordenskjoeldi Icadyptes salasi Peru mya (unit) Paleogene toothed whale Paraptenodytes Neogene Palaeospheniscinae biodiversity clade Antarctic Peninsula Patagonia Aptenodytes Pygoscelis morphology (biology) autapomorph adaptation (biology) habitat allopatric Burdigalian Miocene genus Spheniscus Eudyptula South America carotenoid Antarctic Circumpolar Current Chattian Pliocene latitude Galapagos Penguin Langhian Tortonian global cooling paleoclimatology ice age Spheniscus Middle Miocene Climate Transition Antarctic ice sheet Waimanu grebe homoplasies DNA sequence paleognath fowl waterfowl stork Rallidae seabird Charadriiformes Ciconiiformes Procellariiformes Plotopteridae anhinga cormorant Pelecaniformes Auk Northern Hemisphere convergent evolution Welsh language 2007-03-21 Great Auk Breton language Latin language Tux Linux kernel black tie Happy Feet Surf's Up (film) CGI animal adventure movies March of the Penguins Farce of the Penguins Pingu Silvio Mazzola Emperor Penguin King Penguin Chinstrap Penguin Gentoo Penguin Royal Penguin Southern Rockhopper Penguin Fiordland Penguin Snares Penguin Macaroni Penguin Yellow-eyed Penguin Little Penguin African Penguin Galapagos Penguin Humboldt Penguin Magellanic Penguin adelie iceberg Ross Sea Antarctica Emperor Penguin Emperor Penguin Emperor Penguin Macaroni penguin Chinstrap Penguin Antarctica Southern Elephant Seal King Penguin Proceedings of the Royal Society#Proceedings of the Royal Society B Evolution (journal)
polar_bear	What is the last word on the page?	Connecticut	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is the last word on the page?	(SSN-22)	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is polar bear a mammal?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is polar bear a mammal?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is polar bear a carnivore?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is polar bear a carnivore?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is largest polar bear on record?	2200 lb	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is largest polar bear on record?	A huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960.	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is polar bear's skin color?	white or cream	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is polar bear's skin color?	Black	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How long is polar bear's guard hair?	5-15 cm	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How long is polar bear's guard hair?	5-15 cm	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is cause of polar bear's skin diseases?	mites or other parasites	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What is cause of polar bear's skin diseases?	Mites or other parasites	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Why polar bear is a special species?	The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced.	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What do fossil and DNA evidence tell us?	The polar bear diverged from the brown bear about 200 thousand years ago.	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	What do fossil and DNA evidence tell us?	The polar bear diverged from the brown bear roughly 200 thousand years ago.	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Does a polar bear live in the Arctic?	yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Does a polar bear live in the Arctic?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is a polar bear white in color?	yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is a polar bear white in color?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is a polar bear at high risk of extinction?	yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	Is a polar bear at high risk of extinction?	Yes	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How heavy is a male polar bear?	300-600 kg (660-1320 lb)	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How heavy is a male polar bear?	Most adult males weigh 350-650 kg	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How heavy was the largest polar bear on record?	1002 kg (2200 lb)	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)
polar_bear	How heavy was the largest polar bear on record?	He allegedly weighed 1002 kg	data/set1/a4	polar bear The polar bear (Ursus maritimus) is a bear native to the Arctic. Polar bears and Kodiak bears are the world's largest land carnivores, with most adult males weighing 300-600 kg (660-1320 lb); adult females are about half the size of males. Its fur is hollow and translucent, but usually appears as white or cream colored, thus providing the animal with effective camouflage. Its skin is actually black in color. Its thick blubber and fur insulate it against the cold. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. A semi-aquatic marine mammal, the polar bear has adapted for life on a combination of land, sea, and ice, and is the apex predator within its range. Polar Bears International It feeds mainly on seals, young walruses, and whales, although it will eat anything it can kill. The polar bear is a vulnerable species at high risk of extinction. Zoologists and climatologists believe that the projected decreases in the polar sea ice due to global warming will reduce their population by two thirds by mid-century. Database entry includes a lengthy justification of why this species is listed as vulnerable. . Local long-term studies show that 7 out of 19 subpopulations are declining or already severely reduced. See also HTML excerpts: population status reviews and Table 1 summarizing polar bear population status per 2005. Polar Bears and Conservation and In the USA, the Center for Biological Diversity petitioned to up-list the legal conservation status of polar bears to threatened species in 2005. See also the Center's website on the issue. This petition is still under review. Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. Most adult males weigh 350 650 kg (770 1500+ lb) and measure 2.5 3.0 m (8.2 9.8 ft) in length. Adult females are roughly half the size of males and normally weigh 150 250 kg (330 550 lb), measuring 2 2.5 m (6.6 8.2 ft), but double their weight during pregnancy. Stirling makes no mention of length, these are from SeaWorld The great difference in body size makes the polar bear among the most sexually dimorphic of mammals, surpassed only by the eared seals. At birth, cubs weigh only 600 700 g or about a pound and a half. The largest polar bear on record was a huge male, allegedly weighing 1002 kg (2200 lb) shot at Kotzebue Sound in northwestern Alaska in 1960. A Polar Bear resting. A polar bear's fur provides camouflage and insulation. Although the fur appears white, in fact the individual hairs are translucent, like the water droplets that make up a cloud; the coat may yellow with age. Stiff hairs on the pads of a bear's paws provide insulation and traction on the ice. Polar bears gradually molt their hair from May to August; Kolenosky G. B. 1987. Polar bear. Pp. 475â485 in Wild furbearer management and conservation in North America (M. Novak, J. A. Baker, M. E. Obbard, and B. Malloch, eds.). Ontario Fur Trappers Association, North Bay, Ontario, Canada. however, unlike other Arctic mammals, polar bears do not shed their coat for a darker shade to camouflage themselves in the summer habitat. It was once conjectured that the hollow guard hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. . An infrared image of a polarbear. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 Â°C (50 Â°F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing inside the guard hairs in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again. The guard hair is 5-15 cm over most of the body of polar bears. However, in the forelegs, males have significantly longer, increasing in length until 14 years of age. The ornamental foreleg hair is suggested as a form of an attractive trait for females, likened to the lion mane. The polar bears ears and tail are smaller than other bears, and its legs are stocky, as expected from Allen's rule for a northerly animal. Its feet are very large, however, presumably to distribute load like snowshoes when walking on snow or thin ice. The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract through cannibalism. . Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease. The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death. The ursidae family is believed to have differentiated from other carnivora about 38 million years ago. The ursinae genus originated some 4 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago. The oldest known polar bear fossil is less than 100 thousand years old. Fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear. However, more recent genetic studies have shown that some clades of Brown Bear are more closely related to polar bears than to other brown bears, meaning that the polar bear is not a true species according to some species concepts. Marris, E. 2007. Nature 446, 250-253. Linnaeus at 300: The species and the specious In addition, polar bears can breed with brown bears to produce fertile grizzlyâpolar bear hybrids, . . indicating that they have only recently diverged and are not yet truly distinct species. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species. A comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world. Polar bears still have vestigial hibernation induction trigger in their blood, but they do not hibernate in the winter as the brown bear does. Only female polar bears enter a dormant state referred to as "denning" during pregnancy, though their body temperature does not decrease during this period as it would for a typical mammal in hibernation. . A Polar Bear in Churchill, Manitoba When the polar bear was originally documented, two subspecies were identified: Ursus maritimus maritimus by Constantine J. Phipps in 1774, and Ursus maritimus marinus by Peter S. Pallas in 1776. . This distinction has since been invalidated. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes only one species distributed in nineteen discrete subpopulations across five countries. #Canadian Arctic Archipelago #Greenland, Denmark #Svalbard, Norway #Central Siberia and Franz-Josef Land, Russia #Alaska, USA The 19 subpopulations show seasonal fidelity to geographic areas, but DNA studies show significant interbreeding among them. . Three Polar Bears investigate the submarine USS Honolulu from the North Pole. Mother and two cubs climbing up Guillemot Island, Ukkusiksalik National Park. Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea. The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000. The main population centers are: * Wrangell Island and western Alaska * Northern Alaska * Canadian Arctic archipelago * Greenland * Svalbard-Franz Josef Land * North-Central Siberia Their range is limited by the availability of sea ice which they use as a platform for hunting seals, the mainstay of their diet. Seals and polar bears tend to gather around fissures in the ice called polynyas. . The destruction of its habitat on the Arctic ice threatens the bear's survival as a species. T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba. The most severe and topically recognized threats to the polar bear are the drastic changes taking place in their natural habitat, which is literally melting away due to global warming. . The United States Geological Survey, for example, in November 2006, stated that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs. A 1999 study by scientists from the Canadian Wildlife Service of polar bears in the Hudson Bay showed that global warming is threatening polar bears with starvation. Rising temperatures cause the sea-ice from which the bears hunt to melt earlier in the year, driving them to shore weeks before they have caught enough food to survive the period of scarce food in the late summer and early fall and leading to a 22% decline in the local subpopulation. There is a photographically confirmed case from the beginning of the 20th century of a Svalbard polar bear drifting on ice as far south as the northern coast of the Norwegian mainland. It was found and killed near the village of Berlevag. More recent sightings in Berlevag, including one in the summer of 2005, remain unconfirmed. Polar bears are enormous, aggressive, curious, and potentially dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. Males are normally solitary except for mating season, and females are usually social towards one another. Despite a recurring internet meme that all polar bears are left-handed, . . there is no scientific evidence to support such a contention. Researchers studying polar bears have failed to find any evidence of left-handedness in all bears and one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness. . The polar bear is the most carnivorous member of the bear family. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, . but will eat anything it can kill: birds, eggs, rodents, shellfish, crabs, beluga whales, walrus calves, muskox, reindeer, and other polar bears. Although carnivorous, they have been observed to eat plants, including berries, roots, and kelp, however these do not form a significant part of their diet. Its biology is specialized to digest fat from marine mammals and cannot derive much nutrition from terrestrial food. , Most animals can easily outrun a polar bear on the open land or in the open water, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves taken at the edge of sea-ice in the winter and spring, or on the carcasses of dead adult walruses or whales. They live off of their fat reserves through the late summer and early fall when the sea-ice is at a minimum. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although such an adult walrus kill has been recorded on tape. Polar bear vs Walrus Humans are the only regular predators of polar bears, although the bears have occasionally been found in the stomachs of Orcas. Orcinus orca Orca (Killer Whale) As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers. The resulting high concentrations make the liver poisonous to humans, causing Hypervitaminosis A. . Polar bear diving in a zoo. Polar bears are excellent swimmers and have been seen in open Arctic waters as far as from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005. . Polar bears, being both curious and scavengers will, where they come into contact with humans, investigate and consume garbage. This has been documented at the dump in Churchill, Manitoba prior to its closure. . Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. . . To protect the bears, the Churchill dump was closed in 2006. Garbage is now recycled or transported to Thompson, Manitoba. Hudson Bay Post Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons are known to be toxic to other animals because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency. . Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area. . The relevant chemicals have been classified as persistant organic pollutants by the UN, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and other, have been banned, but their concentrations in polar bear tissues continued to rise for decades as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend. . Mother with cub at Svalbard A mother and cubs in Churchill, Manitoba Polar bears mate in April/May over a one week period needed to induce ovulation. The fertilized egg then remains in a suspended state until August or September. During these 4 months, the females then eat prodigial amounts in preparation for pregnancy, doubling their body weight or more. When food becomes scarce in August because of ice breakup, they dig a maternity den in a snow drift and enter a dormant state similar to hibernation. In areas where food is available year-round, they may not enter a den until October. Cubs are born in December without awakening the mother. She remains dormant while nursing her cubs until the family emerges from the den in March. Cubs are weaned at two or three years of age and are separated from their mother. Sexual maturity typically comes at the age of four, but may be delayed by up to two years. In the 1990's less than 20% cubs in the Western Hudson Bay were weaned at eighteen months, as opposed to 40% of cubs in the early 1980's. In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago. In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year. The USGS has also published research which purports that the percentage of Alaskan polar bears that den on sea ice has changed from 62% between the years 1985-1994, to 37% over the years 1998-2004. The Alaskan population thus now more resembles the world population, in that it is more likely to den on land. . Projected change in polar bear habitat from 2001â2010 to 2041â2050. From USGS The World Conservation Union listed polar bears as a vulnerable species, one of three sub-categories of threatened status, in May 2006. Their latest estimate is that 7 out of 19 subpopulations are declining or already severely reduced. The United States Geological Survey forecasts that two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming. The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080 they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago. Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year. Ice is also breaking up earlier in the year, forcing bears ashore before they have time to build up sufficient fat stores, or forcing them to swim long distances, which may exhaust them, leading to drowning. The results of these effects of global warming have been thinner, stressed bears, decreased reproduction, and lower juvenile survival rates. The Humane Society of the United States "Threats to the Polar Bear's Survival" Polar bear Because of the inaccessibility of the Arctic, there has never been a comprehensive global survey of polar bears, making it difficult to establish a global trend. The earliest preliminary estimates of the global population were around 5,000-10,000 in the early 1970s, but this was revised to 20,000-40,000 in the 1980s. Part of this increase may indicate recovery as a result of conservation measures implemented in the early 1970s, but it is principally a revised estimate based on a growing base of data. Current estimates bound the global population between 20,000-25,000. Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area. In the Western Hudson Bay in Canada, for example, there were an estimated 1194 polar bears in 1987, and 935 in 2004. . The need for species protection has been disputed by two professionals: H. Sterling Burnett and Mitchell K. Taylor. Burnett, a Senior Fellow of the right-wing advocacy group National Center for Policy Analysis, has claimed that the total global population of polar bears increased from 5,000 to 25,000 between the 1970s and 2007. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote a letter to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. These two people have attracted disproportionate media attention, even though their views are refuted by all polar bear scientists. . PBI Ask the Experts First polar bear shot in the S. A. AndrÃ©e's Arctic balloon expedition of 1897. Hunters from around the Arctic have harvested hundreds of polar bears annually since at least the 18th century. The harvest grew rapidly in the 1960's, peaking around 1968 with a global total of 1250 bears that year. Although the polar bear was not deemed endangered at the time, the growing threat encouraged countries to regulate polar bear hunting around that time. Norway passed a series of increasingly strict regulations from 1965 to 1973. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973 the International Agreement on the Conservation of Polar Bears (known as the Oslo Agreement among experts) was signed by the five nations whose Arctic territory is inhabited by polar bears: U.S., Canada, Norway, Denmark (via its territory Greenland) and Russia (then the Soviet Union). Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers), and conduct further research. International Agreement on the Conservation of Polar Bears, November 15, 1973, Oslo Climate Change, Polar Bears, and International Law, Nigel Bankes, University of Calgary Faculty of Law. (DRAFT. Not for quotation.) The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations. All nations except Norway allow hunting by the Inuit, and Canada and Denmark allow trophy hunting by tourists. Many environmental and animal protection groups fear that global warming will have a tremendous impact on the viability of polar bear populations and fear that continued trophy hunting will have further negative consequences. Play fight About 60% of the world's polar bears live in Canada, where conservation laws are a provincial jurisdiction. Hunting quotas and restrictions relating to Indian status are in effect, but vary by province. About 500 bears are killed per year by humans across Canada, a rate believed by scientists to be unsustainable in some areas, notably Baffin Bay. Canada has allowed recreational hunters accompanied by local guides and dog-sled teams since 1970, but the practice was not common until the 1980s. Conservation initiatives conflict with northern resident's income from fur trade and recreational hunting, which can bring in $20,000 to $35,000 Canadian dollars per bear, mostly from American hunters. Inuit are skeptical of conservation concerns because of increases in bear sightings near settlement in recent years. The territory of Nunavut accounts for 80% of Canadian kills. Their government has condemned the American initiative to grant threatened status to polar bears, and northern residents are strongly concerned about it. In 2005 the Government of Nunavut increased the quota from 400 to 518 bears, CBC News, 10 Jan 2005, "Nunavut hunters can kill more polar bears this year" despite protests from some scientific groups. CBC News, 4 Jul 2005, "Rethink polar bear hunt quotas, scientists tell Nunavut hunters" While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s) . Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits. The Government of the Northwest Territories maintain their own quota of 72 - 103 bears within the Inuvialuit communities of which some are set aside for sports hunters. Polar bears at the Detroit Zoo. Because many marine mammal populations had plummeted due to over-hunting, the United States passed the federal Marine Mammal Protection Act in 1972, which prohibited the harassment, injuring or killing of all marine mammal species, including polar bears. This prohibited the importation of polar bear trophies into the U.S. by sport hunters. The Humane Society of the United States "What You Can Do to Protect Polar Bears" In 1994, the United States modified the Marine Mammal Protection Act, allowing the importation of sport-hunted polar bear trophies into the country and clearing the way for an increase in polar bear hunting. Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S. The Humane Society of the United States "Support the Polar Bear Protection Act" In May 2007, legislation was introduced in both houses of the United States Congress (H.R. 2327, called the Polar Bear Protection Act) to reverse the 1994 legislation and ban the importation of dead polar bears. The Humane Society of the United States "The Polar Bear Protection Act" . On June 27 this legislation was defeated in congress and not passed. American Hunter In February 2005 the environmental group, Center for Biological Diversity, with broad support from environmentalists, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. The FWS did not respond to the petition, despite being required to do so within 90 days under United States law. On December 14 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. Global Warming Threatens Polar Bears with Extinction! Tell the Bush Administration to protect polar bears and their critical habitat Russia declared a complete protection in 1955, but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population in October 2000. Until 2005, Greenland placed no limit on hunting by indigenous people. In 2005, it imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time. The Humane Society of the United States "Hitting Polar Bears When They Are Down" Since 1973, Norway has had a complete ban on polar bear hunting. thumbPolar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjÃ¸rne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts. Also, a polar bear was chosen as mascot for the 1988 Winter Olympics held in Calgary, Canada. The Polar Bear is the mascot of Bowdoin college. Both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. East, a young adult book by prolific writer Edith Pattou weaves a story around a mysterious ice bear held in an enchantment by The Troll Queen. East is an ALA Notable Book and is a retelling of the classic story of Beauty and the Beast. * Arctic National Wildlife Refuge * Grizzly-polar bear hybrid * USS Connecticut (SSN-22) ARKive - images and movies of the polar bear (Ursus maritimus) Smithsonian National Museum of Natural History species account-Polar Bear * Nunavut Dept of Environment * USGS Polar Bear Studies Related Wikipedia Articles Animal Chordate Mammal Carnivora bear Ursus (genus) Constantine John Phipps 1774 bear Arctic Kodiak bear carnivore camouflage blubber fur Thermal insulation marine mammal apex predator Pinniped walrus whale vulnerable species Zoologists climatologists sea ice global warming IUCN Center for Biological Diversity threatened species Kodiak bear Carnivora Siberian tiger kilogram metre sexually dimorphic eared seals gram fur camouflage Transparency (optics) cloud guard hair Optical Society of America infrared photography hydrogen peroxide lion Allen's rule snowshoes dermatitis heavy metals ethylene glycol Leptospirosis rabies morbillivirus ursidae carnivora ursinae brown bear fossil Fossils molar (tooth) clades Brown Bear species concept grizzlyâpolar bear hybrid American Society of Mammalogists U.S. Fish and Wildlife Service Ecological niche Phenotype ABC Islands (Alaska) common ancestor hibernation induction trigger Hibernation Dormancy Churchill, Manitoba Constantine J. Phipps Peter S. Pallas Canadian Arctic Archipelago Greenland Denmark Svalbard Norway Siberia Franz-Josef Land Russia Alaska USA seasonal fidelity USS Honolulu (SSN-718) North Pole Ukkusiksalik National Park marine mammal circumpolar Arctic Ocean James Bay Canada Canadian Arctic Svalbard Franz Josef Land Pinniped habitat destruction National Geographic HarperCollins United States Geological Survey Arctic shrinkage Alaska Beaufort Sea Canadian Wildlife Service global warming bear ringed seal beluga whale walrus muskox reindeer berry kelp National Research Council of Canada Human Orcas fish Retinol liver Hypervitaminosis A swimming Waste Landfill Churchill, Manitoba Manitoba styrofoam plastic car batteries ethylene glycol hydraulic fluid motor oil Thompson, Manitoba bioaccumulation halocarbon PCBs pesticides ecological pyramid lipophilicity blubber hormone immunoglobulin G retinol hermaphroditic persistant organic pollutant DDT Svalbard Churchill, Manitoba Manitoba weaning Alaska United States Geological Survey World Conservation Union vulnerable species United States Geological Survey 2050 global warming Arctic archipelago Greenland Hudson Bay Canada National Center for Policy Analysis Heartland Institute Nunavut S. A. AndrÃ©e's Arctic balloon expedition of 1897 IUCN Marine Mammal Protection Act International Agreement on the Conservation of Polar Bears United States Canada Norway Denmark Greenland Russia Soviet Union icebreaker University of Calgary Inuit trophy hunting IUCN Inuit Nunavut Inuit Northwest Territories Inuvialuit Detroit Zoo Marine Mammal Protection Act Center for Biological Diversity United States Fish and Wildlife Service Department of the Interior Endangered Species Act threatened species 14 December 2006 Greenpeace Natural Resources Defense Council California December 27 2006 United States Department of the Interior global warming Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population Coca-Cola Polar Beverages Nelvana Bundaberg Rum Klondike bar penguins Northern Hemisphere Toonie panserbjÃ¸rne His Dark Materials Lost (TV series) 1988 Winter Olympics Bowdoin Canada licence plate East (novel) Edith Pattou Arctic National Wildlife Refuge Grizzly-polar bear hybrid USS Connecticut (SSN-22)

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