context
stringlengths 545
71.9k
| questionsrc
stringlengths 16
10.2k
| question
stringlengths 11
563
|
|---|---|---|
overview social darwinism is a term scholars use to describe the practice of misapplying the biological evolutionary language of charles darwin to politics , the economy , and society . many social darwinists embraced laissez-faire capitalism and racism . they believed that government should not interfere in the “ survival of the fittest ” by helping the poor , and promoted the idea that some races are biologically superior to others . the ideas of social darwinism pervaded many aspects of american society in the gilded age , including policies that affected immigration , imperialism , and public health . charles darwin charles darwin ’ s on the origin of species ( 1859 ) is one of the most important books in the annals of both science and history . in origin and in his subsequent writing darwin offered a revolutionary scientific theory : the process of evolution through natural selection. $ ^1 $ in short , natural selection means that plants and animals evolve over time in nature as new species arise from spontaneous mutations at the point of reproduction and battle with other plants and animals to get food , avoid being killed , and have offspring . darwin pointed to fossil records , among other evidence , in support of his theory . social darwinism soon , some sociologists and others were taking up words and ideas which darwin had used to describe the biological world , and they were adopting them to their own ideas and theories about the human social world . in the late nineteenth and early twentieth centuries , these social darwinists took up the language of evolution to frame an understanding of the growing gulf between the rich and the poor as well as the many differences between cultures all over the world . the explanation they arrived at was that businessmen and others who were economically and socially successful were so because they were biologically and socially “ naturally ” the fittest . conversely , they reasoned that the poor were “ naturally ” weak and unfit and it would be an error to allow the weak of the species to continue to breed . the believed that the dictum “ survival of the fittest ” ( a term coined not by charles darwin but by sociologist herbert spencer ) meant that only the fittest should survive. $ ^2 $ unlike darwin , these sociologists and others were not biologists . they were adapting and corrupting darwin ’ s language for their own social , economic , and political explanations . while darwin ’ s theory remains a cornerstone of modern biology to this day , the views of the social darwinists are no longer accepted , as they were based on an erroneous interpretation of the theory of evolution . social darwinism , poverty , and eugenics social darwinian language like this extended into theories of race and racism , eugenics , the claimed national superiority of one people over another , and immigration law . many sociologists and political theorists turned to social darwinism to argue against government programs to aid the poor , as they believed that poverty was the result of natural inferiority , which should be bred out of the human population . herbert spencer gave as an example a young woman from upstate new york named margaret , whom he described as a “ gutter-child. ” because government aid had kept her alive , margaret had , as spencer wrote , “ proved to be the prolific mother ” of two hundred descendants who were “ idiots , imbeciles , drunkards , lunatics , paupers , and prostitutes. ” spencer concluded by asking , “ was it kindness or cruelty which , generation after generation , enabled these to multiply and become an increasing curse to the society around them ? ” $ ^3 $ these ideas inspired the eugenics movement of the nineteenth and twentieth centuries , which sought to improve the health and intelligence of the human race by sterilizing individuals it deemed `` feeble-minded '' or otherwise `` unfit . '' eugenic sterilizations , which disproportionately targeted women , minorities , and immigrants , continued in the united states until the 1970s. $ ^4 $ social darwinism , immigration , and imperialism the pernicious beliefs of social darwinism also shaped americans ' relationship with peoples of other nations . as a massive number of immigrants came to the united states during the second industrial revolution , white , anglo-saxon americans viewed these newcomers—who differed from earlier immigrants in that they were less likely to speak english and more likely to be catholic or jewish rather than protestant—with disdain . many whites believed that these new immigrants , who hailed from eastern or southern europe , were racially inferior and consequently `` less evolved '' than immigrants from england , ireland , or germany. $ ^5 $ similarly , social darwinism was used as a justification for american imperialism in cuba , puerto rico , and the philippines following the spanish-american war , as many adherents of imperialism argued that it was the duty of white americans to bring civilization to `` backwards '' peoples . during and after world war ii , the arguments of social darwinists and eugenicists lost popularity in the united states due to their association with nazi racial propaganda . modern biological science has completely discredited the theory of social darwinism . what do you think ? describe charles darwin ’ s theory of evolution in your own words . how does it differ from herbert spencer 's idea of social darwinism ? how did the ideas of social darwinism influence politics and society in the gilded age ?
|
during and after world war ii , the arguments of social darwinists and eugenicists lost popularity in the united states due to their association with nazi racial propaganda . modern biological science has completely discredited the theory of social darwinism . what do you think ?
|
why was social darwinism used as a justification ?
|
what is this object ? the bactrian camel was used to haul trade goods along the silk roads leading out of china across the western regions into central asia and beyond . how was it made ? this object was made from light-colored earthenware clays , partly using molds with added sections that were joined together . the insides were often hollow or had holes to prevent unwanted distortion of the object when fired . the polychrome ( multicolored ) glaze is called sancai ( literally `` three colors '' ) , typically made from a lead glaze with mineral pigments of copper ( for green ) , iron ( for brown and amber ) , and cobalt ( for blue ) , and fired at a temperature of about 800–1000 c° . the production of sancai wares flourished between the late 600s and mid-700s , mainly in northern china . before this period , colors on most ceramics were limited to a relatively finite range of green and brown glazed wares . how was it used ? this object was placed in a tomb for the wealthy located in the northern regions of china . tang dynasty ( 618-906 ) tombs of this type were multichambered constructions , often with passageways and niches where such objects would have been placed after the tomb owner ’ s body had been interred and funerary rituals completed . because of the lead glaze , which could be toxic if used in daily activities , such objects would not have been used by the living , but prepared especially for burial . how does this object reflect the life and times when it was made ? objects such as this one , even though it was intended for burial , gives us a colorful view of life during the high tang dynasty ( 618–906 ) . it makes specific reference to the trade routes . camels were used to transport goods across the arid regions of the northwestern part of the tang empire . called the `` ships of the desert , '' these hardy animals could travel long stretches without water , and their padded feet were adapted to traversing the many sand dunes along the way . this camel carries a cushion between its two humps along with mixed cargo ( note the small white vessel below the front hump ) . the cushion is decorated with a comical face . many similar glazed earthenware objects have been found in tang tombs . some have musicians or travelers perched atop the camel . other figures of camels are stacked with bolts of silk . silk was the primary export commodity in demand outside of china . the tang capital of chang-an ( modern xi ’ an ) was transformed into one of the largest and most cosmopolitan cities in the world at that time . it was a magnet for trade and commerce .
|
tang dynasty ( 618-906 ) tombs of this type were multichambered constructions , often with passageways and niches where such objects would have been placed after the tomb owner ’ s body had been interred and funerary rituals completed . because of the lead glaze , which could be toxic if used in daily activities , such objects would not have been used by the living , but prepared especially for burial . how does this object reflect the life and times when it was made ?
|
were the ancient chinese aware of the toxic properties of lead ?
|
what is this object ? the bactrian camel was used to haul trade goods along the silk roads leading out of china across the western regions into central asia and beyond . how was it made ? this object was made from light-colored earthenware clays , partly using molds with added sections that were joined together . the insides were often hollow or had holes to prevent unwanted distortion of the object when fired . the polychrome ( multicolored ) glaze is called sancai ( literally `` three colors '' ) , typically made from a lead glaze with mineral pigments of copper ( for green ) , iron ( for brown and amber ) , and cobalt ( for blue ) , and fired at a temperature of about 800–1000 c° . the production of sancai wares flourished between the late 600s and mid-700s , mainly in northern china . before this period , colors on most ceramics were limited to a relatively finite range of green and brown glazed wares . how was it used ? this object was placed in a tomb for the wealthy located in the northern regions of china . tang dynasty ( 618-906 ) tombs of this type were multichambered constructions , often with passageways and niches where such objects would have been placed after the tomb owner ’ s body had been interred and funerary rituals completed . because of the lead glaze , which could be toxic if used in daily activities , such objects would not have been used by the living , but prepared especially for burial . how does this object reflect the life and times when it was made ? objects such as this one , even though it was intended for burial , gives us a colorful view of life during the high tang dynasty ( 618–906 ) . it makes specific reference to the trade routes . camels were used to transport goods across the arid regions of the northwestern part of the tang empire . called the `` ships of the desert , '' these hardy animals could travel long stretches without water , and their padded feet were adapted to traversing the many sand dunes along the way . this camel carries a cushion between its two humps along with mixed cargo ( note the small white vessel below the front hump ) . the cushion is decorated with a comical face . many similar glazed earthenware objects have been found in tang tombs . some have musicians or travelers perched atop the camel . other figures of camels are stacked with bolts of silk . silk was the primary export commodity in demand outside of china . the tang capital of chang-an ( modern xi ’ an ) was transformed into one of the largest and most cosmopolitan cities in the world at that time . it was a magnet for trade and commerce .
|
because of the lead glaze , which could be toxic if used in daily activities , such objects would not have been used by the living , but prepared especially for burial . how does this object reflect the life and times when it was made ? objects such as this one , even though it was intended for burial , gives us a colorful view of life during the high tang dynasty ( 618–906 ) .
|
what region of t'ang china was this object made in ?
|
when the museo del palacio de bellas artes opened on november 29 , 1934 in mexico city , the general public finally had a chance to see diego rivera 's man , controller of the universe . at 15.75 x 37.5 feet , this epic work demands attentive viewing . less than ten months earlier rivera ’ s first version—originally titled man at the crossroads—was destroyed at rockefeller center in new york city after months of controversy . rivera was in the midst of a prolific period when he began this mural . his retrospective exhibition at moma opened in december 1931 to positive reviews and contemporaneous mural projects in san francisco and detroit enhanced his celebrity as one of the greatest mexican muralists . yet something went amiss with the rockefeller commission : whether it was censorship , a miscommunication or something in between , rivera ’ s man at the crossroads became one of the most infamous artworks that never was . in the later ( surviving ) version at the museo del palacio de bellas artes , man , controller of the universe , a worker at the center directs an enormous machine at the crossroads of the political ideologies dominating this period : capitalism ( to the figure ’ s right ) and communism ( to the figure ’ s left ) . though the composition is bursting with activity , rivera establishes order by using the central figure as a vertical axis : if we fold the scene down the middle , spaces and objects ( like the two giant magnifying glasses ) align . this arrangement encourages comparisons between the two sides . for example , at the top of the capitalist side ( on our left , the central figure 's right ) the brutalities of world war i are on display . rivera underscores how capitalist nations use technology ( poison gas , machine guns , and warplanes ) as destructive forces . by contrast , the top of the communist side ( our right , the central figure 's left ) highlights the glories of the russian revolution , whose momentum overflows into the lower part of the composition . if we continue to focus on the right side , we see key figures in the worker ’ s movement ( león trotsky , friedrich engels , and karl marx ) standing at the foot of a headless classical sculpture brandishing a swastika . as our gaze moves to the lower right , we realize workers are seated on the sculpture ’ s decapitated head . on the other side of the composition , rivera places another classical sculpture ( this one anachronistically wears a christian cross ) . though the figure lacks hands , his face and lightning bolt reveal him as zeus , the supreme greek god . by defacing these classical sculptures , rivera critiques traditional art history ( and its seemingly rarefied tastes ) as well as the political elite ( from the empires of antiquity to the catholic church and fascists ) that—in his view—had repressed the popular masses throughout human history . through this symbolic beheading , the communists have replaced the dominant ideology in europe with a new way of thinking . though the statue on the other side holds a ray of lightning , his handless state renders him powerless amidst the turmoil in capitalist countries : behind the sculpture ’ s base workers in new york city fight against the police while the wealthy ( whose ranks include a bespectacled nelson rockefeller ) , indulge in debauchery between the magnifying glass on the left and the central worker . the “ pie slice ” across from this scene features vladimir lenin holding the hands of workers of distinct races . despite being a small fragment of the mural , this tableau is at the heart of the controversy rivera faced in the united states . though rivera enjoyed tremendous success , he also faced harsh controversy , for both his political beliefs and artistic practice . though he considered his murals at the detroit institute of arts ( 1932-33 ) among his greatest works , his work there faced opposition due to the depiction of men of different races working together . the most notorious controversy of his career came as he painted man at the crossroads , the mural for rockefeller center ’ s radio corporation of america ( rca ) building in 1933 ( the fresco that he later based man , controller of the universe on ) . of the hundreds of characters in man at the crossroads , lenin caused the most debate . an april 24th headline from the new york world-telegram stated “ rivera perpetrates scenes of communist activity for rca walls—and rockefeller , jr. foots bill. ” ten days later nelson rockefeller , rivera ’ s patron and member of a famously wealthy family , asked the artist to remove lenin . when rivera refused , he was paid in full and dismissed . the murals were covered up and later destroyed , as rivera ’ s supporters rallied to save the work . e.b . white ’ s “ i paint what i see , ” written in protest , poignantly highlights this meeting of differing political ideologies : i paint what i paint , i paint what i see , i paint what i think , said rivera [ ... ] i 'll take out a couple of people drinkin' and put in a picture of abraham lincoln ; [ ... ] but the head of lenin has got to stay ! it 's no good taste in a man like me , said john d 's grandson , nelson . [ ... ] for this , as you know , is a public hall . and people want doves , or a tree in fall , and tho your art i dislike to hamper , i owe a little to god and gramper . and after all , it 's my wall… we 'll see if it is , said rivera . [ 1 ] as white predicted , rivera had the last laugh . eight decades later his mural exists in two places : physically , in the museo ; and , as befitting a censored work , thriving in art history scholarship . essay by doris bravo [ 1 ] as quoted from e.b . white , `` i paint what i see '' ( the new yorker , may 1993 ) additional resources : palacio de bellas artes , mexico city detroit fresco cycle diego rivera chronology from moma
|
at 15.75 x 37.5 feet , this epic work demands attentive viewing . less than ten months earlier rivera ’ s first version—originally titled man at the crossroads—was destroyed at rockefeller center in new york city after months of controversy . rivera was in the midst of a prolific period when he began this mural .
|
the essay said diego destroyed man at the crossroads , however the last paragraph has me confused re `` physically , in the museo ; '' , does this mean man at the crossroads still exists ?
|
key points ( adapted from the ap* art history curriculum framework ) periods and definitions prehistory ( or the prehistoric period ) refers to the time before written records , however , human expression existed across the globe long before writing . writing emerged at different times in different parts of the world . the earliest writing is found in ancient mesopotamia , c. 3200 b.c.e . often , art history texts begin with the prehistoric art of europe . however , very early art is found worldwide . homo sapiens ( modern humans are a subspecies ) - homo sapiens migrated out of africa between 120,000 and 50,000 years ago . the stone age is a prehistoric period when stone implements were widely used . the stone age is divided into the paleolithic ( old stone age ) and neolithic ( new stone age ) . after the stone age , the next periods are known as the bronze age and the iron age . historians distinguish the neolithic period by the transition from people living as hunter-gatherers to the development of farming and the domestication of animals . the `` neolithic revolution '' allowed people to create a more settled way of life . this happened at different times in different parts of the world . the first agriculture occurred in southwest asia—in an area historians call the `` fertile crescent . '' prehistory was a time of major shifts in climate and environment . modern archaeology uses a stratigraphic process , where archaeologists precisely record each level and the location of all objects . art making the earliest peoples were hunter-gatherers ( until about 12,000 years ago ) who created imagery in many different media—fired ceramics , painting , sculpture and who built architecture . the oldest “ art ” found to date are rock paintings and sculpture from c. 77,000 years ago . in asia , we have found paleolithic and neolithic cave paintings that feature animal imagery ( in the mountains of central asia and iran ) . animal imagery has also been found in rock shelters throughout central india . in prehistoric china , we find ritual objects created in jade , ( beginning a 5,000-year tradition of working with the precious medium ) . ritual , tomb , and memorializing arts are found across neolithic asia , including impressive funerary steles from saudi arabia and yemen . in europe , we have found small human figural sculptures ( central europe ) , cave paintings ( france and spain ) , and outdoor , monumental stone assemblages ( british isles ) that date from the paleolithic and neolithic periods . in the pacific region , people migrated from asia approximately 45,000 years over land bridges . the earliest created objects have been dated to c. 8,000 years ago . the lapita peoples , who moved eastward from melanesia to polynesia beginning about 4,000 years ago , created pottery with incised geometric designs that appear across the region in multiple media today . on the american continent , peoples who migrated from asia ( before 10,000 b.c.e . ) first made sculptures from animal bone and later from clay . ** ap art history is a registered trademark of the college board , which was not involved in the production of , and does not endorse , this product .
|
the first agriculture occurred in southwest asia—in an area historians call the `` fertile crescent . '' prehistory was a time of major shifts in climate and environment . modern archaeology uses a stratigraphic process , where archaeologists precisely record each level and the location of all objects .
|
hello can you give me a range of time for the following 4 pre-historic ages ?
|
key points ( adapted from the ap* art history curriculum framework ) periods and definitions prehistory ( or the prehistoric period ) refers to the time before written records , however , human expression existed across the globe long before writing . writing emerged at different times in different parts of the world . the earliest writing is found in ancient mesopotamia , c. 3200 b.c.e . often , art history texts begin with the prehistoric art of europe . however , very early art is found worldwide . homo sapiens ( modern humans are a subspecies ) - homo sapiens migrated out of africa between 120,000 and 50,000 years ago . the stone age is a prehistoric period when stone implements were widely used . the stone age is divided into the paleolithic ( old stone age ) and neolithic ( new stone age ) . after the stone age , the next periods are known as the bronze age and the iron age . historians distinguish the neolithic period by the transition from people living as hunter-gatherers to the development of farming and the domestication of animals . the `` neolithic revolution '' allowed people to create a more settled way of life . this happened at different times in different parts of the world . the first agriculture occurred in southwest asia—in an area historians call the `` fertile crescent . '' prehistory was a time of major shifts in climate and environment . modern archaeology uses a stratigraphic process , where archaeologists precisely record each level and the location of all objects . art making the earliest peoples were hunter-gatherers ( until about 12,000 years ago ) who created imagery in many different media—fired ceramics , painting , sculpture and who built architecture . the oldest “ art ” found to date are rock paintings and sculpture from c. 77,000 years ago . in asia , we have found paleolithic and neolithic cave paintings that feature animal imagery ( in the mountains of central asia and iran ) . animal imagery has also been found in rock shelters throughout central india . in prehistoric china , we find ritual objects created in jade , ( beginning a 5,000-year tradition of working with the precious medium ) . ritual , tomb , and memorializing arts are found across neolithic asia , including impressive funerary steles from saudi arabia and yemen . in europe , we have found small human figural sculptures ( central europe ) , cave paintings ( france and spain ) , and outdoor , monumental stone assemblages ( british isles ) that date from the paleolithic and neolithic periods . in the pacific region , people migrated from asia approximately 45,000 years over land bridges . the earliest created objects have been dated to c. 8,000 years ago . the lapita peoples , who moved eastward from melanesia to polynesia beginning about 4,000 years ago , created pottery with incised geometric designs that appear across the region in multiple media today . on the american continent , peoples who migrated from asia ( before 10,000 b.c.e . ) first made sculptures from animal bone and later from clay . ** ap art history is a registered trademark of the college board , which was not involved in the production of , and does not endorse , this product .
|
in the pacific region , people migrated from asia approximately 45,000 years over land bridges . the earliest created objects have been dated to c. 8,000 years ago . the lapita peoples , who moved eastward from melanesia to polynesia beginning about 4,000 years ago , created pottery with incised geometric designs that appear across the region in multiple media today .
|
neolithic - how many years ago was this ?
|
key points ( adapted from the ap* art history curriculum framework ) periods and definitions prehistory ( or the prehistoric period ) refers to the time before written records , however , human expression existed across the globe long before writing . writing emerged at different times in different parts of the world . the earliest writing is found in ancient mesopotamia , c. 3200 b.c.e . often , art history texts begin with the prehistoric art of europe . however , very early art is found worldwide . homo sapiens ( modern humans are a subspecies ) - homo sapiens migrated out of africa between 120,000 and 50,000 years ago . the stone age is a prehistoric period when stone implements were widely used . the stone age is divided into the paleolithic ( old stone age ) and neolithic ( new stone age ) . after the stone age , the next periods are known as the bronze age and the iron age . historians distinguish the neolithic period by the transition from people living as hunter-gatherers to the development of farming and the domestication of animals . the `` neolithic revolution '' allowed people to create a more settled way of life . this happened at different times in different parts of the world . the first agriculture occurred in southwest asia—in an area historians call the `` fertile crescent . '' prehistory was a time of major shifts in climate and environment . modern archaeology uses a stratigraphic process , where archaeologists precisely record each level and the location of all objects . art making the earliest peoples were hunter-gatherers ( until about 12,000 years ago ) who created imagery in many different media—fired ceramics , painting , sculpture and who built architecture . the oldest “ art ” found to date are rock paintings and sculpture from c. 77,000 years ago . in asia , we have found paleolithic and neolithic cave paintings that feature animal imagery ( in the mountains of central asia and iran ) . animal imagery has also been found in rock shelters throughout central india . in prehistoric china , we find ritual objects created in jade , ( beginning a 5,000-year tradition of working with the precious medium ) . ritual , tomb , and memorializing arts are found across neolithic asia , including impressive funerary steles from saudi arabia and yemen . in europe , we have found small human figural sculptures ( central europe ) , cave paintings ( france and spain ) , and outdoor , monumental stone assemblages ( british isles ) that date from the paleolithic and neolithic periods . in the pacific region , people migrated from asia approximately 45,000 years over land bridges . the earliest created objects have been dated to c. 8,000 years ago . the lapita peoples , who moved eastward from melanesia to polynesia beginning about 4,000 years ago , created pottery with incised geometric designs that appear across the region in multiple media today . on the american continent , peoples who migrated from asia ( before 10,000 b.c.e . ) first made sculptures from animal bone and later from clay . ** ap art history is a registered trademark of the college board , which was not involved in the production of , and does not endorse , this product .
|
the earliest writing is found in ancient mesopotamia , c. 3200 b.c.e . often , art history texts begin with the prehistoric art of europe . however , very early art is found worldwide .
|
is there really a prehistoric art which is 77000 yrs old ?
|
walking amidst the endless crowd of tall buildings in chicago ’ s downtown neighborhoods , the twenty-first century viewer , overwhelmed by the colossal hancock tower ( 1970 ) almost misses the comparatively stocky , whole-block office buildings and stores in chicago ’ s loop that first gave rise to the term “ skyscraper ” in the late nineteenth century . at the intersection of state and madison streets , however , one building with large glass windows and a rounded corner entryway covered with lavish decoration stands out . in contrast to its relatively plain neighbors , the pedestrian ’ s eye is immediately attracted to the structure ’ s bronze-colored ground floor and broad white façade stretching twelve stories above it . this is louis sullivan ’ s carson , pirie , scott building , a department store constructed in two stages in 1899 and 1903-04 . sullivan ’ s building is an important example of early chicago skyscraper architecture , and can also be seen as a fascinating indicator of the relationship between architecture and commerce . the firm of adler & amp ; sullivan first became known in chicago in the early 1880s for the design of the auditorium building ( see below ) and other landmarks utilizing new methods of steel frame construction and a uniquely american blend of art nouveau decoration with a simplified monumentality . by the mid-1890s , sullivan struck out on his own and wrote his treatise on skyscraper architecture , “ the tall office building artistically considered , ” in 1896 . in it , sullivan analyzed the problem of high-rise commercial architecture , arguing with his famous phrase “ form must ever follow function ” that a building ’ s design must reflect the social purpose of a particular space . sullivan illustrates this philosophy by describing an ideal tripartite skyscraper . first , there should be a base level with a ground floor for businesses that require easy public access , light , and open space , and a second story also publicly accessible by stairways . these floors should then be followed by an infinite number of stories for offices , designed to look all the same because they serve the same function . finally , the building should be topped with an attic storey and distinct cornice line to mark its endpoint and set it apart from other buildings within the cityscape . for sullivan , the characteristic feature of a skyscraper was that it was tall , and so the building ’ s design should serve that goal by emphasizing its upward momentum . by the turn of the century , sullivan adapted these ideas to a new context , a department store for the schlesinger & amp ; mayer company that was soon purchased by carson , pirie , scott . in contrast to sullivan ’ s earlier office buildings ( like the 1891 wainwright building in st. louis—image left ) , carson , pirie , scott in downtown chicago was intended to meet its patron ’ s needs in a much different way . instead of emphasizing the beehive of identical windows meant to reflect the identical work taking place in each individual office , in the carson pirie scott building , sullivan highlighted instead the lower street-level section and entryway to draw shoppers into the store . this was done in a number of ways . the windows on the ground floor , displaying the store 's products , are much larger than those above . the three doors of the main entrance were placed within a rounded bay on the corner of the site , so that they are visible from all directions approaching the building . the corner entryway and the entire base section are differentiated from the spare upper stories by a unified system of extremely ornate decoration . the cast-iron ornament contains the same highly complicated , delicate , organic and floral motifs that had become hallmarks of sullivan ’ s design aesthetic . for sullivan , the decorative program served a functional project as well , to distinguish the building from those surrounding it , and to make the store attractive to potential customers . the upper parts of the carson , pirie , scott building also reflect sullivan ’ s adaptation of his skyscraper theory to a department store . each successive story of the white terra-cotta façade contains identical windows , in this case the three-sectioned “ chicago ” window common to late nineteenth-century skyscrapers in the city . there is an overhanging cornice at the very top that seems to signify the end of the building ’ s ascent , and makes the slightly set-back attic level distinct from the broad mid-section and the dark cast-iron decoration of the base level . unlike sullivan ’ s office buildings , however , the building ’ s primary thrust is horizontal rather than vertical . sullivan ’ s design emphasizes the long , uninterrupted lines running under each window from each side of the building towards the entry bay , while the decorative base at the bottom and the cornice line at the top flow seamlessly around the corner . the wide rectangular window frames and relatively squat twelve-story frame were intended to meet the specific requirements of a department store , whose mission called for expansive open spaces to display products to customers , not endless individual offices . some later critics like lewis mumford and sigfried giedion viewed the lower , ornamental section of sullivan ’ s carson pirie scott building as an uncomfortable disruption to the otherwise stripped-down , planar style they favored . nevertheless , the building ’ s continuous operation well into the twenty-first century speaks not only to the prestige of sullivan ’ s name , but also to the sustained value of architecture as a corporate symbol . with its elaborate decorative program and attention paid to the functional requirements of retail architecture , sullivan ’ s design was a remarkably successful display for the department store ’ s products , even if it diverged from the wholly vertical effect of his earlier skyscrapers . essay by dr. margaret herman additional resources : louis sullivan , `` the tall office building artistically considered , '' 1896
|
this is louis sullivan ’ s carson , pirie , scott building , a department store constructed in two stages in 1899 and 1903-04 . sullivan ’ s building is an important example of early chicago skyscraper architecture , and can also be seen as a fascinating indicator of the relationship between architecture and commerce . the firm of adler & amp ; sullivan first became known in chicago in the early 1880s for the design of the auditorium building ( see below ) and other landmarks utilizing new methods of steel frame construction and a uniquely american blend of art nouveau decoration with a simplified monumentality .
|
in the second paragraph , when is early ?
|
walking amidst the endless crowd of tall buildings in chicago ’ s downtown neighborhoods , the twenty-first century viewer , overwhelmed by the colossal hancock tower ( 1970 ) almost misses the comparatively stocky , whole-block office buildings and stores in chicago ’ s loop that first gave rise to the term “ skyscraper ” in the late nineteenth century . at the intersection of state and madison streets , however , one building with large glass windows and a rounded corner entryway covered with lavish decoration stands out . in contrast to its relatively plain neighbors , the pedestrian ’ s eye is immediately attracted to the structure ’ s bronze-colored ground floor and broad white façade stretching twelve stories above it . this is louis sullivan ’ s carson , pirie , scott building , a department store constructed in two stages in 1899 and 1903-04 . sullivan ’ s building is an important example of early chicago skyscraper architecture , and can also be seen as a fascinating indicator of the relationship between architecture and commerce . the firm of adler & amp ; sullivan first became known in chicago in the early 1880s for the design of the auditorium building ( see below ) and other landmarks utilizing new methods of steel frame construction and a uniquely american blend of art nouveau decoration with a simplified monumentality . by the mid-1890s , sullivan struck out on his own and wrote his treatise on skyscraper architecture , “ the tall office building artistically considered , ” in 1896 . in it , sullivan analyzed the problem of high-rise commercial architecture , arguing with his famous phrase “ form must ever follow function ” that a building ’ s design must reflect the social purpose of a particular space . sullivan illustrates this philosophy by describing an ideal tripartite skyscraper . first , there should be a base level with a ground floor for businesses that require easy public access , light , and open space , and a second story also publicly accessible by stairways . these floors should then be followed by an infinite number of stories for offices , designed to look all the same because they serve the same function . finally , the building should be topped with an attic storey and distinct cornice line to mark its endpoint and set it apart from other buildings within the cityscape . for sullivan , the characteristic feature of a skyscraper was that it was tall , and so the building ’ s design should serve that goal by emphasizing its upward momentum . by the turn of the century , sullivan adapted these ideas to a new context , a department store for the schlesinger & amp ; mayer company that was soon purchased by carson , pirie , scott . in contrast to sullivan ’ s earlier office buildings ( like the 1891 wainwright building in st. louis—image left ) , carson , pirie , scott in downtown chicago was intended to meet its patron ’ s needs in a much different way . instead of emphasizing the beehive of identical windows meant to reflect the identical work taking place in each individual office , in the carson pirie scott building , sullivan highlighted instead the lower street-level section and entryway to draw shoppers into the store . this was done in a number of ways . the windows on the ground floor , displaying the store 's products , are much larger than those above . the three doors of the main entrance were placed within a rounded bay on the corner of the site , so that they are visible from all directions approaching the building . the corner entryway and the entire base section are differentiated from the spare upper stories by a unified system of extremely ornate decoration . the cast-iron ornament contains the same highly complicated , delicate , organic and floral motifs that had become hallmarks of sullivan ’ s design aesthetic . for sullivan , the decorative program served a functional project as well , to distinguish the building from those surrounding it , and to make the store attractive to potential customers . the upper parts of the carson , pirie , scott building also reflect sullivan ’ s adaptation of his skyscraper theory to a department store . each successive story of the white terra-cotta façade contains identical windows , in this case the three-sectioned “ chicago ” window common to late nineteenth-century skyscrapers in the city . there is an overhanging cornice at the very top that seems to signify the end of the building ’ s ascent , and makes the slightly set-back attic level distinct from the broad mid-section and the dark cast-iron decoration of the base level . unlike sullivan ’ s office buildings , however , the building ’ s primary thrust is horizontal rather than vertical . sullivan ’ s design emphasizes the long , uninterrupted lines running under each window from each side of the building towards the entry bay , while the decorative base at the bottom and the cornice line at the top flow seamlessly around the corner . the wide rectangular window frames and relatively squat twelve-story frame were intended to meet the specific requirements of a department store , whose mission called for expansive open spaces to display products to customers , not endless individual offices . some later critics like lewis mumford and sigfried giedion viewed the lower , ornamental section of sullivan ’ s carson pirie scott building as an uncomfortable disruption to the otherwise stripped-down , planar style they favored . nevertheless , the building ’ s continuous operation well into the twenty-first century speaks not only to the prestige of sullivan ’ s name , but also to the sustained value of architecture as a corporate symbol . with its elaborate decorative program and attention paid to the functional requirements of retail architecture , sullivan ’ s design was a remarkably successful display for the department store ’ s products , even if it diverged from the wholly vertical effect of his earlier skyscrapers . essay by dr. margaret herman additional resources : louis sullivan , `` the tall office building artistically considered , '' 1896
|
for sullivan , the characteristic feature of a skyscraper was that it was tall , and so the building ’ s design should serve that goal by emphasizing its upward momentum . by the turn of the century , sullivan adapted these ideas to a new context , a department store for the schlesinger & amp ; mayer company that was soon purchased by carson , pirie , scott . in contrast to sullivan ’ s earlier office buildings ( like the 1891 wainwright building in st. louis—image left ) , carson , pirie , scott in downtown chicago was intended to meet its patron ’ s needs in a much different way . instead of emphasizing the beehive of identical windows meant to reflect the identical work taking place in each individual office , in the carson pirie scott building , sullivan highlighted instead the lower street-level section and entryway to draw shoppers into the store .
|
how many buildings has carson built in all ?
|
walking amidst the endless crowd of tall buildings in chicago ’ s downtown neighborhoods , the twenty-first century viewer , overwhelmed by the colossal hancock tower ( 1970 ) almost misses the comparatively stocky , whole-block office buildings and stores in chicago ’ s loop that first gave rise to the term “ skyscraper ” in the late nineteenth century . at the intersection of state and madison streets , however , one building with large glass windows and a rounded corner entryway covered with lavish decoration stands out . in contrast to its relatively plain neighbors , the pedestrian ’ s eye is immediately attracted to the structure ’ s bronze-colored ground floor and broad white façade stretching twelve stories above it . this is louis sullivan ’ s carson , pirie , scott building , a department store constructed in two stages in 1899 and 1903-04 . sullivan ’ s building is an important example of early chicago skyscraper architecture , and can also be seen as a fascinating indicator of the relationship between architecture and commerce . the firm of adler & amp ; sullivan first became known in chicago in the early 1880s for the design of the auditorium building ( see below ) and other landmarks utilizing new methods of steel frame construction and a uniquely american blend of art nouveau decoration with a simplified monumentality . by the mid-1890s , sullivan struck out on his own and wrote his treatise on skyscraper architecture , “ the tall office building artistically considered , ” in 1896 . in it , sullivan analyzed the problem of high-rise commercial architecture , arguing with his famous phrase “ form must ever follow function ” that a building ’ s design must reflect the social purpose of a particular space . sullivan illustrates this philosophy by describing an ideal tripartite skyscraper . first , there should be a base level with a ground floor for businesses that require easy public access , light , and open space , and a second story also publicly accessible by stairways . these floors should then be followed by an infinite number of stories for offices , designed to look all the same because they serve the same function . finally , the building should be topped with an attic storey and distinct cornice line to mark its endpoint and set it apart from other buildings within the cityscape . for sullivan , the characteristic feature of a skyscraper was that it was tall , and so the building ’ s design should serve that goal by emphasizing its upward momentum . by the turn of the century , sullivan adapted these ideas to a new context , a department store for the schlesinger & amp ; mayer company that was soon purchased by carson , pirie , scott . in contrast to sullivan ’ s earlier office buildings ( like the 1891 wainwright building in st. louis—image left ) , carson , pirie , scott in downtown chicago was intended to meet its patron ’ s needs in a much different way . instead of emphasizing the beehive of identical windows meant to reflect the identical work taking place in each individual office , in the carson pirie scott building , sullivan highlighted instead the lower street-level section and entryway to draw shoppers into the store . this was done in a number of ways . the windows on the ground floor , displaying the store 's products , are much larger than those above . the three doors of the main entrance were placed within a rounded bay on the corner of the site , so that they are visible from all directions approaching the building . the corner entryway and the entire base section are differentiated from the spare upper stories by a unified system of extremely ornate decoration . the cast-iron ornament contains the same highly complicated , delicate , organic and floral motifs that had become hallmarks of sullivan ’ s design aesthetic . for sullivan , the decorative program served a functional project as well , to distinguish the building from those surrounding it , and to make the store attractive to potential customers . the upper parts of the carson , pirie , scott building also reflect sullivan ’ s adaptation of his skyscraper theory to a department store . each successive story of the white terra-cotta façade contains identical windows , in this case the three-sectioned “ chicago ” window common to late nineteenth-century skyscrapers in the city . there is an overhanging cornice at the very top that seems to signify the end of the building ’ s ascent , and makes the slightly set-back attic level distinct from the broad mid-section and the dark cast-iron decoration of the base level . unlike sullivan ’ s office buildings , however , the building ’ s primary thrust is horizontal rather than vertical . sullivan ’ s design emphasizes the long , uninterrupted lines running under each window from each side of the building towards the entry bay , while the decorative base at the bottom and the cornice line at the top flow seamlessly around the corner . the wide rectangular window frames and relatively squat twelve-story frame were intended to meet the specific requirements of a department store , whose mission called for expansive open spaces to display products to customers , not endless individual offices . some later critics like lewis mumford and sigfried giedion viewed the lower , ornamental section of sullivan ’ s carson pirie scott building as an uncomfortable disruption to the otherwise stripped-down , planar style they favored . nevertheless , the building ’ s continuous operation well into the twenty-first century speaks not only to the prestige of sullivan ’ s name , but also to the sustained value of architecture as a corporate symbol . with its elaborate decorative program and attention paid to the functional requirements of retail architecture , sullivan ’ s design was a remarkably successful display for the department store ’ s products , even if it diverged from the wholly vertical effect of his earlier skyscrapers . essay by dr. margaret herman additional resources : louis sullivan , `` the tall office building artistically considered , '' 1896
|
sullivan ’ s building is an important example of early chicago skyscraper architecture , and can also be seen as a fascinating indicator of the relationship between architecture and commerce . the firm of adler & amp ; sullivan first became known in chicago in the early 1880s for the design of the auditorium building ( see below ) and other landmarks utilizing new methods of steel frame construction and a uniquely american blend of art nouveau decoration with a simplified monumentality . by the mid-1890s , sullivan struck out on his own and wrote his treatise on skyscraper architecture , “ the tall office building artistically considered , ” in 1896 .
|
tell me please , because here there are first features of art deco ?
|
this delicate but large-scale work on paper , which depicts a female nude reclining intimately alongside a wolf , represents the assimilation of several themes that kiki smith has explored throughout her decades-long career . featuring an act of bonding between human and animal , the piece speaks not only to smith ’ s fascination with and reverence for the natural world , but also her noted interests in religious narratives and mythology , the history of figuration in western art , and contemporary notions of feminine domesticity , spiritual yearning , and sexual identity . lying with the wolf is one in a short series of works executed between 2000 and 2002 that illustrates women ’ s relationships with animals , drawing from representations found in visual , literary , and oral histories . smith is most interested in narratives that speak to collectively shared mythologies ; these include folk tales , biblical stories and victorian literature , yet the once-familiar stories are then fragmented and conflated with one another to form new clusters of meaning and association . intimate relationships with nature many of smith ’ s works from this period feature a female protagonist who is based on little red riding hood as well sainte geneviève , the patron saint of paris . geneviève is herself often associated with saint francis of assisi because of her close relationships with animals and her ability , in particular , to domesticate wolves . other works in the series include geneviève and the may wolf__— a bronze sculpture in which a standing female figure calmly embraces the wolf—and rapture , which is perhaps more closely aligned to red riding hood , as it depicts a woman stepping out from the stomach of the recumbent creature . the pair as depicted in lying with the wolf , however , seems locked in a more intimate embrace , as the wolf nuzzles affectionately into the nude woman ’ s arms . she wraps herself around the animal ’ s body in a gesture of comforting , her fingers stroking the soft fur beneath its ears and along the side of its stomach . the wolf ’ s wildness is tamed , and both figures seem to nurture one another , floating within the abstract space of the textured paper surface upon which they are delicately drawn . smith imbues a story that is normally quite violent with a kind of tenderness that is characteristic of her overall aesthetic . feminist approaches to narrative it has been suggested by some critics that smith ’ s reinterpretations of red riding hood and sainte geneviève represent a feminist approach to popular folktales . this is supported by her placement of “ woman ” amidst the natural world , but also , importantly , at a structural level : in the way in which the two narratives are fragmented and combined . borrowing from divergent sources in order to forge a new storyline , smith demonstrates the slippery relationship between a visual image and its multiple references , adopting a narrative style indebted to feminist re-writings of history . as the curator helaine posner has explained : “ instead of presenting them in their traditional roles as predator and prey , smith re-imagined these characters as companions , equals in purpose and scale. ” the distinction between “ predator ” and “ prey ” might be thought of as a metaphor for hierarchies of power in human relationships , which have traditionally been drawn along the lines of gender , race , and class . because patriarchal societies typically grant more power to men , while requiring women to be submissive or dependent , we can think of this “ overturning ” in smith ’ s art as a political statement against such inequalities . the artistic narratives portrayed in her work are ones in which binaries are flipped and opposing qualities are merged ; in so doing , smith asserts a critical feminist position that favors the articulation of multiple meanings . “ walking around in a garden ” `` my career has stopped being linear . a couple of years ago , the story line or narrative fell apart ... '' * as is the case with lying with the wolf , several of smith ’ s works integrate a diverse list of themes and motifs that she has accumulated over the course of her career . the artist continuously re-imagines tropes she has used in past works , with the result that her practice does not seem to progress through discrete artistic stages . rather , she works in cycles and layers ; she has described her career as an act of meandering , or “ walking around in a garden. ” kiki smith grew up in a vibrant artistic family ; she is the daughter of the sculptor tony smith and the opera singer jane lawrence smith . she has spoken fondly of the victorian house in which she was raised in south orange , new jersey , and how it captured her young imagination , as a historical artifact with its own memories and indices to the past . the notion of “ home ” has been central to her practice , and she likens it to the human body , a theme that is pervasive across her oeuvre . domesticity , fragility , and the humble materials of craft and folk arts feature strongly in her work . abjection and the body while kiki smith ’ s early work is aligned with the collaborative and activist art scene of the 1980s , she became known for intimate explorations of the human body in the following decade , often through life-sized sculpture that honored the figural tradition in western art . these works emphasized the body ’ s vulnerability and made reference to feminist theories of the “ abject , ” which conceived of the body as a messy , porous , and boundary-less system . blood pool , for instance , features a small , apparently violated figure , huddled into a fetal position on the floor . many other works of this period feature bodily fluids or marks of injury . mysticism and mythologies throughout the 1990s , smith would come to embrace her religious upbringing , creating works that are spiritual , ethereal , and markedly more decorative . celestial motifs and references to the natural world became ubiquitous , although these themes are still deeply connected to the body . as an investigation of the body in its capacity for fertility , reproduction , and nurturing , this turn towards the natural environment would eventually lead smith to her interest in animals and our connections to them . lying with the wolf is an extension of this yearning to connect the earthly with the spiritual and the personal with the collective . essay by allison young *as quoted in christopher lyon , “ free fall : kiki smith on her art ” in kiki smith , ed . helaine posner and christopher lyon , new york , ny : the monacelli press , inc : page 37 .
|
these works emphasized the body ’ s vulnerability and made reference to feminist theories of the “ abject , ” which conceived of the body as a messy , porous , and boundary-less system . blood pool , for instance , features a small , apparently violated figure , huddled into a fetal position on the floor . many other works of this period feature bodily fluids or marks of injury .
|
clearly the woman figure is on the ground in a highly vulnerable position , but is that all we take from it ?
|
this delicate but large-scale work on paper , which depicts a female nude reclining intimately alongside a wolf , represents the assimilation of several themes that kiki smith has explored throughout her decades-long career . featuring an act of bonding between human and animal , the piece speaks not only to smith ’ s fascination with and reverence for the natural world , but also her noted interests in religious narratives and mythology , the history of figuration in western art , and contemporary notions of feminine domesticity , spiritual yearning , and sexual identity . lying with the wolf is one in a short series of works executed between 2000 and 2002 that illustrates women ’ s relationships with animals , drawing from representations found in visual , literary , and oral histories . smith is most interested in narratives that speak to collectively shared mythologies ; these include folk tales , biblical stories and victorian literature , yet the once-familiar stories are then fragmented and conflated with one another to form new clusters of meaning and association . intimate relationships with nature many of smith ’ s works from this period feature a female protagonist who is based on little red riding hood as well sainte geneviève , the patron saint of paris . geneviève is herself often associated with saint francis of assisi because of her close relationships with animals and her ability , in particular , to domesticate wolves . other works in the series include geneviève and the may wolf__— a bronze sculpture in which a standing female figure calmly embraces the wolf—and rapture , which is perhaps more closely aligned to red riding hood , as it depicts a woman stepping out from the stomach of the recumbent creature . the pair as depicted in lying with the wolf , however , seems locked in a more intimate embrace , as the wolf nuzzles affectionately into the nude woman ’ s arms . she wraps herself around the animal ’ s body in a gesture of comforting , her fingers stroking the soft fur beneath its ears and along the side of its stomach . the wolf ’ s wildness is tamed , and both figures seem to nurture one another , floating within the abstract space of the textured paper surface upon which they are delicately drawn . smith imbues a story that is normally quite violent with a kind of tenderness that is characteristic of her overall aesthetic . feminist approaches to narrative it has been suggested by some critics that smith ’ s reinterpretations of red riding hood and sainte geneviève represent a feminist approach to popular folktales . this is supported by her placement of “ woman ” amidst the natural world , but also , importantly , at a structural level : in the way in which the two narratives are fragmented and combined . borrowing from divergent sources in order to forge a new storyline , smith demonstrates the slippery relationship between a visual image and its multiple references , adopting a narrative style indebted to feminist re-writings of history . as the curator helaine posner has explained : “ instead of presenting them in their traditional roles as predator and prey , smith re-imagined these characters as companions , equals in purpose and scale. ” the distinction between “ predator ” and “ prey ” might be thought of as a metaphor for hierarchies of power in human relationships , which have traditionally been drawn along the lines of gender , race , and class . because patriarchal societies typically grant more power to men , while requiring women to be submissive or dependent , we can think of this “ overturning ” in smith ’ s art as a political statement against such inequalities . the artistic narratives portrayed in her work are ones in which binaries are flipped and opposing qualities are merged ; in so doing , smith asserts a critical feminist position that favors the articulation of multiple meanings . “ walking around in a garden ” `` my career has stopped being linear . a couple of years ago , the story line or narrative fell apart ... '' * as is the case with lying with the wolf , several of smith ’ s works integrate a diverse list of themes and motifs that she has accumulated over the course of her career . the artist continuously re-imagines tropes she has used in past works , with the result that her practice does not seem to progress through discrete artistic stages . rather , she works in cycles and layers ; she has described her career as an act of meandering , or “ walking around in a garden. ” kiki smith grew up in a vibrant artistic family ; she is the daughter of the sculptor tony smith and the opera singer jane lawrence smith . she has spoken fondly of the victorian house in which she was raised in south orange , new jersey , and how it captured her young imagination , as a historical artifact with its own memories and indices to the past . the notion of “ home ” has been central to her practice , and she likens it to the human body , a theme that is pervasive across her oeuvre . domesticity , fragility , and the humble materials of craft and folk arts feature strongly in her work . abjection and the body while kiki smith ’ s early work is aligned with the collaborative and activist art scene of the 1980s , she became known for intimate explorations of the human body in the following decade , often through life-sized sculpture that honored the figural tradition in western art . these works emphasized the body ’ s vulnerability and made reference to feminist theories of the “ abject , ” which conceived of the body as a messy , porous , and boundary-less system . blood pool , for instance , features a small , apparently violated figure , huddled into a fetal position on the floor . many other works of this period feature bodily fluids or marks of injury . mysticism and mythologies throughout the 1990s , smith would come to embrace her religious upbringing , creating works that are spiritual , ethereal , and markedly more decorative . celestial motifs and references to the natural world became ubiquitous , although these themes are still deeply connected to the body . as an investigation of the body in its capacity for fertility , reproduction , and nurturing , this turn towards the natural environment would eventually lead smith to her interest in animals and our connections to them . lying with the wolf is an extension of this yearning to connect the earthly with the spiritual and the personal with the collective . essay by allison young *as quoted in christopher lyon , “ free fall : kiki smith on her art ” in kiki smith , ed . helaine posner and christopher lyon , new york , ny : the monacelli press , inc : page 37 .
|
the artistic narratives portrayed in her work are ones in which binaries are flipped and opposing qualities are merged ; in so doing , smith asserts a critical feminist position that favors the articulation of multiple meanings . “ walking around in a garden ” `` my career has stopped being linear . a couple of years ago , the story line or narrative fell apart ... '' * as is the case with lying with the wolf , several of smith ’ s works integrate a diverse list of themes and motifs that she has accumulated over the course of her career .
|
is the coloration around her legs and arm supposed to be blood ?
|
this delicate but large-scale work on paper , which depicts a female nude reclining intimately alongside a wolf , represents the assimilation of several themes that kiki smith has explored throughout her decades-long career . featuring an act of bonding between human and animal , the piece speaks not only to smith ’ s fascination with and reverence for the natural world , but also her noted interests in religious narratives and mythology , the history of figuration in western art , and contemporary notions of feminine domesticity , spiritual yearning , and sexual identity . lying with the wolf is one in a short series of works executed between 2000 and 2002 that illustrates women ’ s relationships with animals , drawing from representations found in visual , literary , and oral histories . smith is most interested in narratives that speak to collectively shared mythologies ; these include folk tales , biblical stories and victorian literature , yet the once-familiar stories are then fragmented and conflated with one another to form new clusters of meaning and association . intimate relationships with nature many of smith ’ s works from this period feature a female protagonist who is based on little red riding hood as well sainte geneviève , the patron saint of paris . geneviève is herself often associated with saint francis of assisi because of her close relationships with animals and her ability , in particular , to domesticate wolves . other works in the series include geneviève and the may wolf__— a bronze sculpture in which a standing female figure calmly embraces the wolf—and rapture , which is perhaps more closely aligned to red riding hood , as it depicts a woman stepping out from the stomach of the recumbent creature . the pair as depicted in lying with the wolf , however , seems locked in a more intimate embrace , as the wolf nuzzles affectionately into the nude woman ’ s arms . she wraps herself around the animal ’ s body in a gesture of comforting , her fingers stroking the soft fur beneath its ears and along the side of its stomach . the wolf ’ s wildness is tamed , and both figures seem to nurture one another , floating within the abstract space of the textured paper surface upon which they are delicately drawn . smith imbues a story that is normally quite violent with a kind of tenderness that is characteristic of her overall aesthetic . feminist approaches to narrative it has been suggested by some critics that smith ’ s reinterpretations of red riding hood and sainte geneviève represent a feminist approach to popular folktales . this is supported by her placement of “ woman ” amidst the natural world , but also , importantly , at a structural level : in the way in which the two narratives are fragmented and combined . borrowing from divergent sources in order to forge a new storyline , smith demonstrates the slippery relationship between a visual image and its multiple references , adopting a narrative style indebted to feminist re-writings of history . as the curator helaine posner has explained : “ instead of presenting them in their traditional roles as predator and prey , smith re-imagined these characters as companions , equals in purpose and scale. ” the distinction between “ predator ” and “ prey ” might be thought of as a metaphor for hierarchies of power in human relationships , which have traditionally been drawn along the lines of gender , race , and class . because patriarchal societies typically grant more power to men , while requiring women to be submissive or dependent , we can think of this “ overturning ” in smith ’ s art as a political statement against such inequalities . the artistic narratives portrayed in her work are ones in which binaries are flipped and opposing qualities are merged ; in so doing , smith asserts a critical feminist position that favors the articulation of multiple meanings . “ walking around in a garden ” `` my career has stopped being linear . a couple of years ago , the story line or narrative fell apart ... '' * as is the case with lying with the wolf , several of smith ’ s works integrate a diverse list of themes and motifs that she has accumulated over the course of her career . the artist continuously re-imagines tropes she has used in past works , with the result that her practice does not seem to progress through discrete artistic stages . rather , she works in cycles and layers ; she has described her career as an act of meandering , or “ walking around in a garden. ” kiki smith grew up in a vibrant artistic family ; she is the daughter of the sculptor tony smith and the opera singer jane lawrence smith . she has spoken fondly of the victorian house in which she was raised in south orange , new jersey , and how it captured her young imagination , as a historical artifact with its own memories and indices to the past . the notion of “ home ” has been central to her practice , and she likens it to the human body , a theme that is pervasive across her oeuvre . domesticity , fragility , and the humble materials of craft and folk arts feature strongly in her work . abjection and the body while kiki smith ’ s early work is aligned with the collaborative and activist art scene of the 1980s , she became known for intimate explorations of the human body in the following decade , often through life-sized sculpture that honored the figural tradition in western art . these works emphasized the body ’ s vulnerability and made reference to feminist theories of the “ abject , ” which conceived of the body as a messy , porous , and boundary-less system . blood pool , for instance , features a small , apparently violated figure , huddled into a fetal position on the floor . many other works of this period feature bodily fluids or marks of injury . mysticism and mythologies throughout the 1990s , smith would come to embrace her religious upbringing , creating works that are spiritual , ethereal , and markedly more decorative . celestial motifs and references to the natural world became ubiquitous , although these themes are still deeply connected to the body . as an investigation of the body in its capacity for fertility , reproduction , and nurturing , this turn towards the natural environment would eventually lead smith to her interest in animals and our connections to them . lying with the wolf is an extension of this yearning to connect the earthly with the spiritual and the personal with the collective . essay by allison young *as quoted in christopher lyon , “ free fall : kiki smith on her art ” in kiki smith , ed . helaine posner and christopher lyon , new york , ny : the monacelli press , inc : page 37 .
|
other works in the series include geneviève and the may wolf__— a bronze sculpture in which a standing female figure calmly embraces the wolf—and rapture , which is perhaps more closely aligned to red riding hood , as it depicts a woman stepping out from the stomach of the recumbent creature . the pair as depicted in lying with the wolf , however , seems locked in a more intimate embrace , as the wolf nuzzles affectionately into the nude woman ’ s arms . she wraps herself around the animal ’ s body in a gesture of comforting , her fingers stroking the soft fur beneath its ears and along the side of its stomach . the wolf ’ s wildness is tamed , and both figures seem to nurture one another , floating within the abstract space of the textured paper surface upon which they are delicately drawn .
|
the forearm and hands seems to be missing , perhaps chewed off by an animal or symbolising something to do with having ones hands taken away ?
|
gauguin ’ s return to paris from his first stay in tahiti in august 1893 did not go quite as he had hoped : no fanfare , no hero ’ s welcome , and most disappointingly of all no sales . gauguin and “ art pottery ” despite some critical interest in his work , success still seemed to elude him . what was more , after years of support , his wife mette cut off any ties with him . broke and without a family , he went to brittany where living costs were cheaper , but readjusting to life in “ civilized ” france proved a challenge . a drunken brawl with a bunch of breton sailors shattered his ankle , an injury from which he would never completely recover . enough was enough , apparently . in june 1895 he departed for tahiti never to return . it is in this tempestuous period that he produced arguably his masterpiece in the medium of ceramics : oviri . from wood-carvings and ceramics to highly finished marble works , sculpture was integral to gauguin ’ s artistic practice . his works in clay , all produced in paris in the mid-80 ’ s to the mid-90 ’ s , owe much to the great ceramist ernest chaplet who offered gauguin assistance in firing and glazing as well as access to his kiln in rue blomet , montparnasse . oviri was the largest and the last of these series . ceramics appealed to him for several reasons ; the first was financial , not only is clay cheap , but given its practical usages , gauguin hoped , misguidedly as it turned out , that his pottery would attract more buyers than his painting . then there was his famous love of non-european art , such as the inca and pre-columbian pottery he encountered in his peruvian childhood . gauguin viewed such works—both decorative and utilitarian—as capable of expressing profound emotions as much so-called high art , hence the term “ art pottery ” he used to describe them . gauguin was not entirely alone in wishing to elevate this humble medium . towards the end of the nineteenth century there was a noticeable crumbling of the hierarchies that had separated the fine artist from the craftsman , the distinction say between the liberal and the mechanical artist which had held sway since the renaissance . in tahitian culture there were no such fine distinctions , instead , the craftsman/artist was defined quite differently , as gauguin came to discover , being neither warrior/hunter nor homemaker/carer , over there he was neither fully male nor fully female but occupied , socially speaking , an androgynous middle ground somewhere between the two . this ambiguous sense of gendered identity appealed to gauguin ’ s subversive spirit . certainly the creative potential of androgyny intrigued him and is often commented on in discussions of oviri . oviri a shortened form of oviri-moe-aihere ( the savage who sleeps in the wild forest ) , the tahitian goddess of death and mourning , the name itself fascinated gauguin : savage , brutal , bloodthirsty . he used it , like a nom de guerre , to refer to himself , as though taking on the goddess ’ s terrible aspects . here she stands , then : under her feet a dead she-wolf ; in her hands the crushed form of its cub ; the red glaze suggestive of the trickling flow of their blood . there is no known source for the episode , which was probably gauguin ’ s invention . this left the way open for various interpretations : that the wolves represent the savagery of the goddess herself ; that by killing them she is somehow absorbing their violent capabilities ; even that they are gauguin himself . in a number of letters he draws the comparison , recalling , for instance , how degas once described him as “ the hungry wolf without a collar. ” others see a veiled allusion to the practice of infanticide , outlawed by the time of gauguin ’ s arrival , that was carried out by the areoi , tahiti ’ s priestly elite . the image evokes notions of sacrifice or perhaps stories of the vengeful mother archetype , drawing connections between oviri and delacroix ’ s medea about to kill her children of 1838 . whatever story it tells , its earliest manifestations in terms of design can be traced to a work produced two years earlier during his first stay in tahiti , where are you going ? it is here , in the stocky , sculptural and distinctly androgynous frame of the foreground figure , carrying in her arms a wolf-cub that we get our first glimpse of oviri . how different the ceramic is to the painting , though . perhaps due to the personal crisis that he experienced on his return to paris or perhaps due to the medium itself with its direct contact between hand and clay . oviri is a far more radical departure , an atavistic assault on the canons of grace , harmony and beauty . ugly seems hardly adequate to describe this twisted and condensed avatar of primal , destructive forces , the huge goggle eyes floating inhumanly around her disproportioned head . the block-like figure , lacking any piercings or projecting parts , like egyptian statuary , commands a frontal view . when seen from the back , though , we are presented with a wholly different image , another work of art almost . what had looked from the front to be hair appears now as a cocoon-like covering , the chrysalis underneath , incipient , on the point of breaking out . the contrast with oviri , the murderess , is striking . from this angle , the work also bears a striking likeness to rodin ’ s balzac , a sculpture he had been working on since 1891 . although not exhibited publicly until 1898 , gauguin certainly knew of the commission and perhaps was aware of the direction rodin was taking with it . in both works we find the same dramatic reduction of form , rejecting any reference to the classical past , tapping instead into a more primordial impulse , in oviri 's case a force at once female and male , in which the destructive , death-wielding act of crushing the wolf-cub finds its creative , life-giving antithesis in the organic , bud-like form of its reverse . a grave marker it was this confounding of the ultimate boundary , that between death and life , that might well have prompted gauguin in 1900 , knowing that he had not long to live , to ask a friend to send him his oviri from paris intending it for his tombstone . his friend never got round to it ; a merciful oversight given the stoneware would not have weathered well in that tropical climate . instead it went on to feature in the artist ’ s retrospective of 1906 , an exhibition picasso saw and most probably drew inspiration from when composing his les demoiselles d ’ avignon . in 1978 , a bronze cast was made of the sculpture , which was placed before gauguin ’ s grave in the marquesas . acknowledged as a masterpiece , in 1987 the original entered the collection of the musée d ’ orsay . essay by ben pollitt additional resources this sculpture at the musée d ’ orsay barbara landy , `` the meaning of gauguin 's 'oviri ' ceramic , '' burlington magazine , vol . 109 ( 1967 ) , pp . 242 , 244-246 . ( jstor )
|
oviri was the largest and the last of these series . ceramics appealed to him for several reasons ; the first was financial , not only is clay cheap , but given its practical usages , gauguin hoped , misguidedly as it turned out , that his pottery would attract more buyers than his painting . then there was his famous love of non-european art , such as the inca and pre-columbian pottery he encountered in his peruvian childhood .
|
what were the `` practical '' applications of the clay works that gauguin was producing ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ?
|
other then disease , what other things or events decreased the population of native americans ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote .
|
why is there a question asked about mercantilism in the previous quiz when in fact , it is only introduced in this section ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact .
|
what kind of disease was the most deadly ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today .
|
why was sugar so important ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency .
|
would n't salt be the first global commodity ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world .
|
do you happen to have a simple definition ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state .
|
why did the indians body ( immune system ) could n't repel the incoming viruses and other ... when the past topic ( native indian topic ) said that their bodies were well-nourished , strong and prepared ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ?
|
how did tea affect cultural norms in europe and the americas ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption .
|
why was the demand for slaves so high ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries .
|
were paying jobs an abstract idea back then ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ?
|
were languages ( like englush or portuguese ) exchanged in the columbian exchange ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom .
|
does every country/state/continent have a cash crop ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange .
|
why did so many more natives die of diseases they were not immune too than europeans ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange .
|
i 'm sure there were diseases that killed lives stalk and maybe crops , right ?
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world . the process by which commodities , people , and diseases crossed the atlantic is known as the columbian exchange . commerce in the new world as europeans expanded their market reach into the colonial sphere , they devised a new economic policy to ensure the colonies ’ profitability . the philosophy of mercantilism shaped european perceptions of wealth from the 1500s to the late 1700s . mercantilism held that only a limited amount of wealth , as measured in gold and silver bullion , existed in the world . in order to gain power , nations had to amass wealth by mining these precious raw materials from their colonial possessions . mercantilists did not believe in free trade , arguing instead that the nation should control trade to create wealth and to enhance state power . in this view , colonies existed to strengthen the colonizing nation . colonial mercantilism , a set of protectionist policies designed to benefit the colonizing nation , relied on several factors : colonies rich in raw materials cheap labor colonial loyalty to the home government control of the shipping trade under this system , the colonies sent their raw materials—harvested by enslaved people or native workers—to europe . european industry then produced and sent finished materials—like textiles , tools , manufactured goods , and clothing—back to the colonies . colonists were forbidden from trading with other countries . commodification quickly affected production in the new world . american silver , tobacco , and other items—which were used by native peoples for ritual purposes—became european commodities with monetary value . before the arrival of the spanish , for example , the inca people of the andes consumed chicha , a corn beer , for ritual purposes only . when the spanish discovered chicha , they bought and traded for it , detracting from its spiritual significance for market gain . this process disrupted native economies and spurred early commercial capitalism . the columbian exchange : goods introduced by europe , produced in new world as europeans traversed the atlantic , they brought with them plants , animals , and diseases that changed lives and landscapes on both sides of the ocean . these two-way exchanges between the americas and europe/africa are known collectively as the columbian exchange . of all the commodities in the atlantic world , sugar proved to be the most important . indeed , in the colonial era , sugar carried the same economic importance as oil does today . european rivals raced to create sugar plantations in the americas and fought wars for control of production . although refined sugar was available in the old world , europe ’ s harsher climate made sugarcane difficult to grow . columbus brought sugar to hispaniola in 1493 , and the new crop thrived . over the next century of colonization , caribbean islands and most other tropical areas became centers of sugar production , which in turn fueled the demand to enslave africans for labor . the columbian exchange : from the new world to the old world though of secondary importance to sugar , tobacco also had great value for europeans as a cash crop—a crop cultivated for sale instead of personal consumption . native americans had been growing tobacco for medicinal and ritual purposes for centuries before european contact , believing tobacco could improve concentration and enhance wisdom . to some , its use meant achieving an entranced , altered , or divine state . tobacco was unknown in europe before 1492 , and it carried a negative stigma at first . the early spanish explorers considered native people 's use of tobacco to be proof of their savagery . however , european colonists then took up the habit of smoking , and they brought it across the atlantic . europeans ascribed medicinal properties to tobacco , claiming that it could cure headaches and skin irritations . even so , europeans did not import tobacco in great quantities until the 1590s . at that time , it became the first truly global commodity ; english , french , dutch , spanish , and portuguese colonists all grew it for the world market . native peoples also introduced europeans to chocolate , made from cacao seeds and used by the aztec in mesoamerica as currency . mesoamerican indians consumed unsweetened chocolate in a drink with chili peppers , vanilla , and a spice called achiote . this chocolate drink—xocolatl—was part of ritual ceremonies like marriage . chocolate contains theobromine , a stimulant , which may be why native people believed it brought them closer to the sacred world . the columbian exchange : from the old world to the new world the crossing of the atlantic by plants like cacao and tobacco illustrates the ways in which the discovery of the new world changed the habits and behaviors of europeans . europeans changed the new world in turn , not least by bringing old world animals to the americas . on his second voyage , christopher columbus brought pigs , cows , chickens , and horses to the islands of the caribbean . many native americans used horses to transform their hunting and gathering into a highly mobile practice . travelers between the americas , africa , and europe also included microbes : silent , invisible life forms that had profoundly devastating consequences . native peoples had no immunity to old world diseases to which they had never been exposed . european explorers unwittingly brought with them chickenpox , measles , mumps , and smallpox , decimating some populations and wholly destroying others . one disease did travel the other direction—syphilis , a lethal sexually transmitted disease , came with travelers from the new world to europe for the first time . the columbian exchange embodies both the positive and negative environmental and health results of contact as well as the cultural shifts produced by such contact . what do you think ? what was the best commodity introduced to the new world by the columbian exchange ? what was the worst ? how did the columbian exchange shift cultural norms of native americans ? of european colonizers ? try to draw your own diagram of the columbian exchange on a world map .
|
overview mercantilism , an economic theory that rejected free trade and promoted government regulation of the economy for the purpose of enhancing state power , defined the economic policy of european colonizing countries . christopher columbus introduced horses , sugar plants , and disease to the new world , while facilitating the introduction of new world commodities like sugar , tobacco , chocolate , and potatoes to the old world .
|
what was the most deadly ?
|
summary of customary units of volume cups | pints | quarts | gallons : - : | : - : | : - : | : - : $ 16 $ | $ 8 $ | $ 4 $ | $ \goldd1 $ $ 4 $ | $ 2 $ | $ \goldd1 $ | $ \dfrac14 $ $ 2 $ | $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac18 $ $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac14 $ | $ \dfrac { 1 } { 16 } $ what is volume ? volume measures capacity . for example , the volume of a bowl is the amount of space inside the bowl or how much water , for example it would take to fill the bowl . in the us customary system of measurement , the most common units of volume are cups , pints , quarts and gallons . how big are customary units of volume ? a juice box contains about $ 1 $ cup of liquid . a pint is equal to $ 2 $ cups . a water bottle contains about $ 1 $ pint of liquid . a quart is equal to $ 2 $ pints . a large shampoo bottle contains about $ 1 $ quart of liquid . a gallon is equal to $ 4 $ quarts . a milk jug contains about $ 1 $ gallon of liquid . want to learn more about customary units of volume ? check out this video . practice set 1 : estimating volume want to try more problems like this ? check out this exercise , converting larger units to smaller units $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ 1 \text { quart } = \greend { 4 } \text { cups } $ $ 1 \text { quart } = \greend { 2 } \text { pints } $ $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ to convert larger units to smaller units we multiply the number of larger units by the green conversion factor for the appropriate smaller units . example : converting gallons to quarts $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ $ \blued { 2 } \text { gallons } = \blued { 2 } \times \greend { 4 } =8\text { quarts } $ example : converting pints to cups $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ \blued { 8 } \text { pints } = \blued { 8 } \times \greend { 2 } =16\text { cups } $ converting smaller units to larger units $ 1\text { cup } = \dfrac1 { \purple { 2 } } \text { pint } $ $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ 1\text { quart } = \dfrac1 { \purple { 4 } } \text { gallon } $ to convert smaller units to larger units we divide the number of smaller units by the purple conversion factor for the appropriate larger units . example : converting pints to quarts $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ \pink { 12 } \text { pints } = \dfrac { \pink { 12 } } { \purple { 2 } } = \pink { 12 } \div\purple { 2 } =\blue6\text { quarts } $ want to learn more about converting between units of volume ? check out this video . practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
why do we only multiply and divide when we convert ?
|
summary of customary units of volume cups | pints | quarts | gallons : - : | : - : | : - : | : - : $ 16 $ | $ 8 $ | $ 4 $ | $ \goldd1 $ $ 4 $ | $ 2 $ | $ \goldd1 $ | $ \dfrac14 $ $ 2 $ | $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac18 $ $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac14 $ | $ \dfrac { 1 } { 16 } $ what is volume ? volume measures capacity . for example , the volume of a bowl is the amount of space inside the bowl or how much water , for example it would take to fill the bowl . in the us customary system of measurement , the most common units of volume are cups , pints , quarts and gallons . how big are customary units of volume ? a juice box contains about $ 1 $ cup of liquid . a pint is equal to $ 2 $ cups . a water bottle contains about $ 1 $ pint of liquid . a quart is equal to $ 2 $ pints . a large shampoo bottle contains about $ 1 $ quart of liquid . a gallon is equal to $ 4 $ quarts . a milk jug contains about $ 1 $ gallon of liquid . want to learn more about customary units of volume ? check out this video . practice set 1 : estimating volume want to try more problems like this ? check out this exercise , converting larger units to smaller units $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ 1 \text { quart } = \greend { 4 } \text { cups } $ $ 1 \text { quart } = \greend { 2 } \text { pints } $ $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ to convert larger units to smaller units we multiply the number of larger units by the green conversion factor for the appropriate smaller units . example : converting gallons to quarts $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ $ \blued { 2 } \text { gallons } = \blued { 2 } \times \greend { 4 } =8\text { quarts } $ example : converting pints to cups $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ \blued { 8 } \text { pints } = \blued { 8 } \times \greend { 2 } =16\text { cups } $ converting smaller units to larger units $ 1\text { cup } = \dfrac1 { \purple { 2 } } \text { pint } $ $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ 1\text { quart } = \dfrac1 { \purple { 4 } } \text { gallon } $ to convert smaller units to larger units we divide the number of smaller units by the purple conversion factor for the appropriate larger units . example : converting pints to quarts $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ \pink { 12 } \text { pints } = \dfrac { \pink { 12 } } { \purple { 2 } } = \pink { 12 } \div\purple { 2 } =\blue6\text { quarts } $ want to learn more about converting between units of volume ? check out this video . practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
whats the difference between customary units and metric units for capacity ?
|
summary of customary units of volume cups | pints | quarts | gallons : - : | : - : | : - : | : - : $ 16 $ | $ 8 $ | $ 4 $ | $ \goldd1 $ $ 4 $ | $ 2 $ | $ \goldd1 $ | $ \dfrac14 $ $ 2 $ | $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac18 $ $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac14 $ | $ \dfrac { 1 } { 16 } $ what is volume ? volume measures capacity . for example , the volume of a bowl is the amount of space inside the bowl or how much water , for example it would take to fill the bowl . in the us customary system of measurement , the most common units of volume are cups , pints , quarts and gallons . how big are customary units of volume ? a juice box contains about $ 1 $ cup of liquid . a pint is equal to $ 2 $ cups . a water bottle contains about $ 1 $ pint of liquid . a quart is equal to $ 2 $ pints . a large shampoo bottle contains about $ 1 $ quart of liquid . a gallon is equal to $ 4 $ quarts . a milk jug contains about $ 1 $ gallon of liquid . want to learn more about customary units of volume ? check out this video . practice set 1 : estimating volume want to try more problems like this ? check out this exercise , converting larger units to smaller units $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ 1 \text { quart } = \greend { 4 } \text { cups } $ $ 1 \text { quart } = \greend { 2 } \text { pints } $ $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ to convert larger units to smaller units we multiply the number of larger units by the green conversion factor for the appropriate smaller units . example : converting gallons to quarts $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ $ \blued { 2 } \text { gallons } = \blued { 2 } \times \greend { 4 } =8\text { quarts } $ example : converting pints to cups $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ \blued { 8 } \text { pints } = \blued { 8 } \times \greend { 2 } =16\text { cups } $ converting smaller units to larger units $ 1\text { cup } = \dfrac1 { \purple { 2 } } \text { pint } $ $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ 1\text { quart } = \dfrac1 { \purple { 4 } } \text { gallon } $ to convert smaller units to larger units we divide the number of smaller units by the purple conversion factor for the appropriate larger units . example : converting pints to quarts $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ \pink { 12 } \text { pints } = \dfrac { \pink { 12 } } { \purple { 2 } } = \pink { 12 } \div\purple { 2 } =\blue6\text { quarts } $ want to learn more about converting between units of volume ? check out this video . practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
for example , the volume of a bowl is the amount of space inside the bowl or how much water , for example it would take to fill the bowl . in the us customary system of measurement , the most common units of volume are cups , pints , quarts and gallons . how big are customary units of volume ?
|
what are the differences between us and other capacities ?
|
summary of customary units of volume cups | pints | quarts | gallons : - : | : - : | : - : | : - : $ 16 $ | $ 8 $ | $ 4 $ | $ \goldd1 $ $ 4 $ | $ 2 $ | $ \goldd1 $ | $ \dfrac14 $ $ 2 $ | $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac18 $ $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac14 $ | $ \dfrac { 1 } { 16 } $ what is volume ? volume measures capacity . for example , the volume of a bowl is the amount of space inside the bowl or how much water , for example it would take to fill the bowl . in the us customary system of measurement , the most common units of volume are cups , pints , quarts and gallons . how big are customary units of volume ? a juice box contains about $ 1 $ cup of liquid . a pint is equal to $ 2 $ cups . a water bottle contains about $ 1 $ pint of liquid . a quart is equal to $ 2 $ pints . a large shampoo bottle contains about $ 1 $ quart of liquid . a gallon is equal to $ 4 $ quarts . a milk jug contains about $ 1 $ gallon of liquid . want to learn more about customary units of volume ? check out this video . practice set 1 : estimating volume want to try more problems like this ? check out this exercise , converting larger units to smaller units $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ 1 \text { quart } = \greend { 4 } \text { cups } $ $ 1 \text { quart } = \greend { 2 } \text { pints } $ $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ to convert larger units to smaller units we multiply the number of larger units by the green conversion factor for the appropriate smaller units . example : converting gallons to quarts $ 1 \text { gallon } = \greend { 4 } \text { quarts } $ $ \blued { 2 } \text { gallons } = \blued { 2 } \times \greend { 4 } =8\text { quarts } $ example : converting pints to cups $ 1 \text { pint } = \greend { 2 } \text { cups } $ $ \blued { 8 } \text { pints } = \blued { 8 } \times \greend { 2 } =16\text { cups } $ converting smaller units to larger units $ 1\text { cup } = \dfrac1 { \purple { 2 } } \text { pint } $ $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ 1\text { quart } = \dfrac1 { \purple { 4 } } \text { gallon } $ to convert smaller units to larger units we divide the number of smaller units by the purple conversion factor for the appropriate larger units . example : converting pints to quarts $ 1\text { pint } = \dfrac1 { \purple { 2 } } \text { quart } $ $ \pink { 12 } \text { pints } = \dfrac { \pink { 12 } } { \purple { 2 } } = \pink { 12 } \div\purple { 2 } =\blue6\text { quarts } $ want to learn more about converting between units of volume ? check out this video . practice set 2 : converting units of volume want to try more problems like this ? check out these exercises : convert larger units to smaller units converting between units
|
summary of customary units of volume cups | pints | quarts | gallons : - : | : - : | : - : | : - : $ 16 $ | $ 8 $ | $ 4 $ | $ \goldd1 $ $ 4 $ | $ 2 $ | $ \goldd1 $ | $ \dfrac14 $ $ 2 $ | $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac18 $ $ \goldd1 $ | $ \dfrac12 $ | $ \dfrac14 $ | $ \dfrac { 1 } { 16 } $ what is volume ? volume measures capacity .
|
what is the density of the substance in g/ml ?
|
key points : in interspecies competition , two species use the same limited resource . competition has a negative effect on both of the species ( -/- interaction ) . a species ' niche is basically its ecological role , which is defined by the set of conditions , resources , and interactions it needs ( or can make use of ) . the competitive exclusion principle says that two species ca n't coexist if they occupy exactly the same niche ( competing for identical resources ) . two species whose niches overlap may evolve by natural selection to have more distinct niches , resulting in resource partitioning . introduction humans compete with other humans all the time – for jobs , athletic prizes , dates , you name it . but do we compete with other species ? if you 've ever gone camping and had you food stolen by an enterprising raccoon , bear , or other critter , you 've had a little taste of interspecific competition – competition between members of different species that use overlapping , limited resources . resources are often limited in a habitat , and many species may compete to get ahold of them . for instance , plants in a garden may compete with each other for soil nutrients , water , and light . the overall effect of interspecific competition is negative for both species that participate ( a -/- interaction ) . that is , each species would do better if the other species were n't there . in this article , we 'll look at the concept of an ecological niche and see how species having similar niches can lead to competition . we 'll also see how species can evolve by natural selection to occupy more different niches , thus divvying up resources and minimizing competition . the niche concept a species ' niche is its ecological role or `` way of life , '' which is defined by the full set of conditions , resources , and interactions it needs ( or can make use of ) $ ^1 $ . each species fits into an ecological community in its own special way and has its own tolerable ranges for many environmental factors . for example , a fish species ' niche might be defined partly by ranges of salinity ( saltiness ) , ph ( acidity ) , and temperature it can tolerate , as well as the types of food it can eat . as we 'll see , two organisms with exactly the same niche ca n't survive in the same habitat ( because they compete for exactly the same resources , so one will drive the other to extinction ) . however , species whose niches only partly overlap may be able to coexist . also , over long periods of time , they may evolve to make use of more different , or less overlapping , sets of resources . competitive exclusion principle the competitive exclusion principle tells us that two species ca n't have exactly the same niche in a habitat and stably coexist . that 's because species with identical niches also have identical needs , which means they would compete for precisely the same resources . a famous example of the competitive exclusion principle is shown in the figure below , which features two types of single-celled microorganisms , paramecium aurelia and paramecium caudatum . when grown individually in the lab , both species thrive . but when they are grown in the same test tube ( habitat ) with a fixed amount of nutrients , both grow more poorly and p. aurelia eventually outcompetes p. caudatum for food , leading to p. caudatum 's extinction . in nature , it 's rarely the case that two species occupy exactly identical niches . however , the greater the extent to which two species ' niches overlap , the stronger the competition between them will tend to be $ ^2 $ . resource partitioning competitive exclusion may be avoided if one or both of the competing species evolves to use a different resource , occupy a different area of the habitat , or feed during a different time of day . the result of this kind of evolution is that two similar species use largely non-overlapping resources and thus have different niches . this is called resource partitioning , and it helps the species coexist because there is less direct competition between them . the anole lizards found on the island of puerto rico are a good example of resource partitioning . in this group , natural selection has led to the evolution of different species that make use of different resources . the figure below shows resource partitioning among $ 11 $ species of anole lizards . each species lives in its own preferred habitat , which is defined by type and height of vegetation ( trees , shrubs , cactus , etc . ) , sunlight , and moisture , among other factors .
|
for example , a fish species ' niche might be defined partly by ranges of salinity ( saltiness ) , ph ( acidity ) , and temperature it can tolerate , as well as the types of food it can eat . as we 'll see , two organisms with exactly the same niche ca n't survive in the same habitat ( because they compete for exactly the same resources , so one will drive the other to extinction ) . however , species whose niches only partly overlap may be able to coexist .
|
why ca n't there be a type of wasps and bees that feed on the exact same thing ( assuming they did ) and yet not drive each other to extinction ?
|
key points : in interspecies competition , two species use the same limited resource . competition has a negative effect on both of the species ( -/- interaction ) . a species ' niche is basically its ecological role , which is defined by the set of conditions , resources , and interactions it needs ( or can make use of ) . the competitive exclusion principle says that two species ca n't coexist if they occupy exactly the same niche ( competing for identical resources ) . two species whose niches overlap may evolve by natural selection to have more distinct niches , resulting in resource partitioning . introduction humans compete with other humans all the time – for jobs , athletic prizes , dates , you name it . but do we compete with other species ? if you 've ever gone camping and had you food stolen by an enterprising raccoon , bear , or other critter , you 've had a little taste of interspecific competition – competition between members of different species that use overlapping , limited resources . resources are often limited in a habitat , and many species may compete to get ahold of them . for instance , plants in a garden may compete with each other for soil nutrients , water , and light . the overall effect of interspecific competition is negative for both species that participate ( a -/- interaction ) . that is , each species would do better if the other species were n't there . in this article , we 'll look at the concept of an ecological niche and see how species having similar niches can lead to competition . we 'll also see how species can evolve by natural selection to occupy more different niches , thus divvying up resources and minimizing competition . the niche concept a species ' niche is its ecological role or `` way of life , '' which is defined by the full set of conditions , resources , and interactions it needs ( or can make use of ) $ ^1 $ . each species fits into an ecological community in its own special way and has its own tolerable ranges for many environmental factors . for example , a fish species ' niche might be defined partly by ranges of salinity ( saltiness ) , ph ( acidity ) , and temperature it can tolerate , as well as the types of food it can eat . as we 'll see , two organisms with exactly the same niche ca n't survive in the same habitat ( because they compete for exactly the same resources , so one will drive the other to extinction ) . however , species whose niches only partly overlap may be able to coexist . also , over long periods of time , they may evolve to make use of more different , or less overlapping , sets of resources . competitive exclusion principle the competitive exclusion principle tells us that two species ca n't have exactly the same niche in a habitat and stably coexist . that 's because species with identical niches also have identical needs , which means they would compete for precisely the same resources . a famous example of the competitive exclusion principle is shown in the figure below , which features two types of single-celled microorganisms , paramecium aurelia and paramecium caudatum . when grown individually in the lab , both species thrive . but when they are grown in the same test tube ( habitat ) with a fixed amount of nutrients , both grow more poorly and p. aurelia eventually outcompetes p. caudatum for food , leading to p. caudatum 's extinction . in nature , it 's rarely the case that two species occupy exactly identical niches . however , the greater the extent to which two species ' niches overlap , the stronger the competition between them will tend to be $ ^2 $ . resource partitioning competitive exclusion may be avoided if one or both of the competing species evolves to use a different resource , occupy a different area of the habitat , or feed during a different time of day . the result of this kind of evolution is that two similar species use largely non-overlapping resources and thus have different niches . this is called resource partitioning , and it helps the species coexist because there is less direct competition between them . the anole lizards found on the island of puerto rico are a good example of resource partitioning . in this group , natural selection has led to the evolution of different species that make use of different resources . the figure below shows resource partitioning among $ 11 $ species of anole lizards . each species lives in its own preferred habitat , which is defined by type and height of vegetation ( trees , shrubs , cactus , etc . ) , sunlight , and moisture , among other factors .
|
resource partitioning competitive exclusion may be avoided if one or both of the competing species evolves to use a different resource , occupy a different area of the habitat , or feed during a different time of day . the result of this kind of evolution is that two similar species use largely non-overlapping resources and thus have different niches . this is called resource partitioning , and it helps the species coexist because there is less direct competition between them .
|
what happens when two organisms fight for the same resources ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light .
|
how did danish physiologist come up with the idea to cut off the tip of a coleoptile ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore .
|
what is the difference between plant and animal cell ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light .
|
i am curious , is negative phototropism a simple derivative of the positive phototropism as a mandatory part of the nomenclature , or is it actually a well-described phenomenon ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell .
|
i am struggling to connect the link between phytochromes , cryptochromes and phototropins - are the phytochromes dominant in red and far red light situations and then these effects are taken over by the blue light dominant proteins ( plus zaxanthin ) ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore .
|
could you limit the amount of red-spectrum light a plant receives to stimulate growth , as phytochromes help determine whether or not the plant is being shaded by its neighbors , or would that not work ?
|
key points plants have a variety of developmental , physiological , and growth responses to light—sometimes only to particular wavelengths of light . in phototropism a plant bends or grows directionally in response to light . shoots usually move towards the light ; roots usually move away from it . in photoperiodism flowering and other developmental processes are regulated in response to the photoperiod , or day length . short-day plants flower when day length is below a certain threshold , while long-day plants flower when day length is above a certain threshold . in many plants , photoperiodism is controlled by the overlap between the day length cue and the plant 's internal circadian rhythms . introduction almost all plants can photosynthesize , and photosynthesis is key to these plants ' survival : it lets them make sugar molecules that serve as fuel and building materials . but plants respond to light—sometimes , to specific wavelengths of light—in other ways as well . these non-photosynthesis-related responses allow plants to adjust to their environment and optimize growth . for instance , some types of seeds will germinate only when they receive a sufficient amount of light—along with other cues . other plants have ways to detect if they are in the shade of neighboring plants based on the quality of light they receive . they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore . when the chromophore absorbs light , it causes a change in the shape of the protein , altering its activity and starting a signaling pathway . the signaling pathway results in a response to the light cue , such as a change in gene expression , growth , or hormone production . in this article , we will focus on two examples of plant responses to light and explore how these responses allow plants to match their growth to their environments : phototropism is a directional response that allows plants to grow towards , or in some cases away from , a source of light . photoperiodism is the regulation of physiology or development in response to day length . photoperiodism allows some plant species to flower—switch to reproductive mode—only at certain times of the year . let 's take a look at how these light responses work ! phototropism one important light response in plants is phototropism , which involves growth toward—or away from—a light source . positive phototropism is growth towards a light source ; negative phototropism is growth away from light . shoots , or above-ground parts of plants , generally display positive phototropism—they bend toward the light . this response helps the green parts of the plant get closer to a source of light energy , which can then be used for photosynthesis . roots , on the other hand , will tend to grow away from light. $ ^1 $ phototropism involves a mobile signal in 1880 , charles darwin and his son francis published a paper in which they described the bending of grass seedlings towards light . specifically , they examined this response in very young plants that had just sprouted whose leaves and shoots were still covered by a sheath called the coleoptile . the father-and-son team analyzed the bending response using experiments in which they covered either the tip or the lower part of the coleoptile. $ ^1 $ through these experiments , they found that light was perceived at the coleoptile 's tip . however , the response—bending , at a cellular level , unequal elongation of cells—took place well below the tip . they concluded that some kind of signal must be sent downwards from the coleoptile ’ s tip towards its base . in 1913 , danish physiologist peter boysen-jensen followed up on this work by showing that a chemical signal produced at the tip was indeed responsible for the bending response : he first cut off the tip of a coleoptile , covered the cut section with a block of gelatin , and replaced the tip . the coleoptile was able to bend normally when it was exposed to light . when he tried the experiment again using an impermeable flake of mica instead of gelatin , the coleoptile lost the ability to bend in response to light . only the gelatin—which allowed a chemical signal to travel through its pores—could allow the necessary communication between tip and base . through a variation on this experiment , boysen-jensen was also able to show that the mobile signal traveled on the shaded side of the seedling . when the mica plate was stuck in on the illuminated side , the plant could still bend towards the light , but when it was stuck in on the shaded side , the bending response no longer occurred . the results of this experiment also implied that the signal was a growth stimulant rather than a growth repressor since the phototropic response involved faster cell elongation on the shaded side than on the lit side . phototropins and auxin today , we know that proteins called phototropins are the main photoreceptors responsible for light detection during phototropism—the name is a handy reminder of their role ! like other plant photoreceptors , phototropins are made up of a protein bound to a light-absorbing organic molecule , called the chromophore . phototropins absorb light in the blue range of the spectrum . when they absorb light , they change shape , become active , and can change the activity of other proteins in the cell . when a coleoptile is exposed to a source of light , phototropin molecules on the illuminated side absorb lots of light , while molecules on the shady side absorb much less . through mechanisms that are still not well understood , these different levels of phototropin activation cause a plant hormone called auxin to be transported unequally down the two sides of the coleoptile . more auxin is transported down the shady side , and less auxin is transported down the illuminated side . auxin promotes cell elongation , causing the plant to grow more on the shady side and bend in the direction of the light source . photoperiodism some types of plants require particular day or night lengths in order to flower—that is , to transition to the reproductive phase of their life cycle . plants that flower only when day length drops below a certain threshold are called short-day plants . rice is an example of a short-day plant. $ ^2 $ plants that flower only when day length rises above a certain threshold are called long-day plants . spinach and sugar beets are long-day plants. $ ^2 $ by flowering only when day or night lengths reach a certain threshold , these plants are able to coordinate their flowering time with changes in the seasons . not all plants are short-day or long-day . some plants are day-neutral , meaning that flowering does not depend on day length . also , flowering is not the only trait that can be regulated by photoperiod—day length—although it 's the one that 's gotten the most attention from researchers . tuber formation in potatoes , for instance , is also under photoperiodic control , as is bud dormancy in preparation for winter in trees growing in cold areas. $ ^3 $ what is the plant actually measuring ? although we classify plants as short-day or long-day , in some cases , plants may actually be measuring the length of the night . that is , it can be the length of the period of continuous darkness , not the length of the period of continuous light , that determines whether or not the plant flowers . this is particularly true of short-day plants , whose photoperiodic response is often tightly linked to the length of the night . typical short-day plants share the following characteristics : $ ^ { 2,4,5 } $ the flower when the day is short and the night is long . they do not flower when the day is long and the night is short . they do not flower when the long night is interrupted by a brief period of light . they do not flower when the long day is interrupted by a brief period of dark . what exactly does all that tell us ? the pattern in the diagram above means that short-day plants measure the length of the night—the continuous period of darkness—and not the length of the day—the continuous period of light . that is , a short-day plant will only flower if it gets uninterrupted darkness for a length of time that meets or exceeds its flowering threshold . if there is an interruption to the darkness , such as a brief period of light , the plant will not flower , even though the continuous period of light—day—is still short . the situation changes a bit when we consider long-day plants . some long-day plants do measure the length of the night , like the short-day plants in the diagram above . however , unlike short-day plants , these long-day plants need the period of darkness to be shorter than or equal to a critical length ! long-day plants that measure the night length are said to be dark-dominant because it 's the period of continuous darkness that 's important for flowering . many other long-day plant species , however , seem to measure the length of the day , not the night , in determining when to flower . these plants are said to be light-dominant. $ ^6 $ scientists think that the majority of long-day plant species are actually light-dominant , while the majority of short-day plant species are dark-dominant. $ ^6 $ how does the plant determine day or night length ? this is a question plant biologists have been wondering about for decades ! many models have been suggested over the years , but today , most biologists think photoperiodism—at least , in many species—is the result of interactions between a plant 's `` body clock '' and light cues from its environment . only when the light cues and the body clock line up in the right way will the plant flower . this model is called the external coincidence model of photoperiodism . its name highlights that an external cue—day length—has to coincide in a certain way with the plant 's internal rhythms in order to trigger flowering . these rhythms are circadian rhythms , patterns in gene expression or physiology that repeat on a 24-hour cycle and are driven by the plant 's internal body clock . how the external coincidence model works is best understood for the long-day plant arabidopsis , a relative of mustard . in this plant , levels of a specific m $ \text { rna } $ that encodes a flowering induction protein rise and fall on a circadian cycle , with m $ \text { rna } $ levels going up sharply in the evening. $ ^ { 2,7 } $ when there is no light in the evening , the high levels of m $ \text { rna } $ do n't get the plant very far . that 's because the flowering induction protein is usually broken down as soon as it 's made . if , however , there 's light in the evening—a long day—photoreceptors are activated by the light and jump in to save the protein from degradation . the protein can then build up and trigger flowering. $ ^ { 2,7,8 } $ thanks to this molecular system , the plant flowers only when the days are long—when light extends late enough to overlap with the high m $ \text { rna } $ expression . other models of photoperiodism although it seems likely that many plant species use some type of external coincidence model to control flowering and other photoperiod-regulated processes , different plants have different genes and `` wiring '' . it 's possible that some plant species have fundamentally different ways of measuring photoperiod and linking this information to developmental changes . for instance , an older model of photoperiodism , the phytochrome hourglass model , does not depend on overlap between circadian rhythms and photoperiod length . instead , it suggests that phytochromes could act as a clock to measure the length of the night . although this model is no longer widely accepted , it could potentially be valid for certain types of plants .
|
they can increase their upward growth to outcompete their neighbors and get a bigger share of sunshine . plant responses to light depend , logically enough , on the plant ’ s ability to sense light . light sensing in plants involves special molecules called photoreceptors , which are made up of a protein linked to a light-absorbing pigment called a chromophore .
|
would that change how quickly the plant produces seeds or fruit ?
|
overview the byzantine empire was the eastern continuation of the roman empire after the western roman empire 's fall in the fifth century ce . it lasted from the fall of the roman empire until the ottoman conquest in 1453 . continuities : the byzantine empire initially maintained many roman systems of governance and law and aspects of roman culture . the byzantines called themselves `` roman '' . the term `` byzantine empire '' was not used until well after the fall of the empire . changes : the byzantine empire shifted its capital from rome to constantinople , changed the official religion to christianity , and changed the official language from latin to greek . from rome to byzantium the fall of the roman empire was a pivotal moment in world history . but we sometimes forget that part of the roman empire continued on . even though the western roman empire , which was centered around rome , collapsed , the eastern roman empire survived as the byzantine empire . the byzantine empire lasted for a millennium after the fall of the roman empire , ending with the ottoman conquests in 1453 . while the roman empire 's capital was rome ( for most of its history ) , the byzantine empire ’ s capital city was constantinople , which was previously called byzantium , and today is istanbul . the capital was well-positioned near active trade routes connecting east and west . constantinople was named after emperor constantine i , the first byzantine emperor . in this article , we 're going to look at some of the continuities between the roman empire and the byzantine empire . we 'll also examine some of the changes that occurred , transforming the eastern roman empire into the byzantine empire . the roman empire in the east transformed into the byzantine empire over time , so it 's pretty hard to neatly separate the histories of the two empires , but most scholars agree that emperor constantine 's reign was the start of the byzantine empire . constantine—who ruled from 324 ce to 337 ce—made some significant changes to the roman empire . two of these changes were the new capital at byzantium and the new christian character of the empire ( constantine legalized christianity and eventually converted himself ) . these changes eventually created a distinct culture which would characterize the byzantine empire after the fall of the western roman empire in 476 . even so , people living under the byzantine empire continued to see themselves as romans and continued to refer to their empire as the roman empire ; the terms byzantine empire and eastern roman empire were created much later . even though the byzantine empire is considered to start with constantine 's moving the capital to byzantium , it was not considered a separate empire by historians until the fall of the western roman empire in 476 . even during this overlap , the nature of the eastern and western halves of the empire began to diverge . in particular , the greek language became more and more important in the east relative to latin . in addition , constantine legalized christianity . however , this was still a period of transition . it was n't until later , under theodosius i—who ruled from 379 ce to 395 ce—that christianity became the official state religion of the roman empire ( both east and west ) . during constantine 's rule , there was a mix of christian and pagan elements . let 's look at this passage written by the historian timothy e. gregory : there can be no doubt that , from 312 ce onward , constantine favored the christian church and that he offered it considerable wealth . he clearly became deeply involved in the religious controversies of the age and he favored christians in the employ of the state . at the same time , constantine continued to hold the office of pontifex maximus ( chief priest of the state religion ) , and pagan symbols continued to appear on his coins , at least until 323 ce . the early byzantine state once the western roman empire fell to germanic conquerors in 476 ce , the eastern empire continued on as what historians would later refer to as the byzantine empire . the first truly strong byzantine emperor was justinian—who ruled the byzantine empire from 482 ce to 565 ce . he was able to reclaim much of the western empire during his reign . emperor justinian also built upon roman ideas when he put forth a unified roman legal code . prior to his reign , roman laws had differed from region to region and many contradicted one another . it was during justinian ’ s reign that many of the most notable buildings and works of art in the byzantine empire were completed . in constantinople , the hagia sophia was constructed under justinian ’ s orders . at the time , it was the largest church in the world . justinian also contributed to constantinople ’ s growth by creating trade routes linking the capital to major cities to the east and west . a changing empire even after justinian ’ s efforts to reunify the byzantine empire , reconquer territory , and institute reforms , the stability of the byzantine empire was at risk . attacks from neighboring groups—including the persians , slavs , arabs , and turkic steppe people—weakened the integrity of the empire . the empire also lacked revenues and struggled to keep up with mounting military expenses . emperor heraclius ’ —who ruled from 610 ce to 641 ce—responded to these threats with a new set of reforms . he restructured the military , paying for it by clamping down on corruption and increasing taxes . he also started putting less gold in coins so he could mint more of them , enabling him to pay more soldiers . despite these reforms , wars with the arabs and the slavs significantly damaged the byzantine empire and reduced its territory drastically . though the government organization had stayed very much the same since the time of the romans , the byzantine empire began to transform in more drastic ways in the aftermath of these devastating wars . how did it change ? let 's read this passage written by byzantine scholar robert browning : since the days of diocletian and constantine , at the turn of the third and fourth centuries , rigid separation of civil and military authority had been the rule . civilian governors of provinces had no authority over troops stationed in their area . army commanders had none over the civilian population . [ ... ] it was a system designed to keep generals from dabbling in politics and staging military coups , and it worked . but it was cumbersome , it depended on the cooperation of the governing bodies of cities , which had to undertake much of the execution of government policy , and it made coordination of military and civil policy slow and difficult . now that no region of the empire was safe from attack , something different was needed . [ ... ] territories still under byzantine control were formed into military districts under the command of a strategos ( army leader ) , who was responsible for all aspects of government , civil and military . [ ... ] these new military districts were called themes , a word whose primary connotation is that of a division of troops . in the passage , browning described the emergence of the theme system . during heraclius ' rule the byzantine empire switched from the provincial administration system to this new system . under the theme system , land was granted to farmers who , in return , provided the empire with loyal soldiers . each district was called a theme . the efficiency of this system allowed the empire to keep hold of asia minor . the previous system of provinces was a civil administration , but the theme system fused civil administration with military administration . this system was fairly successful . because there was not enough money to pay soldiers , land grants were able to subsidize the military . also , soldiers had a personal stake in the land since it was their own . by the early eighth century , the byzantine empire began to look very different from the roman empire . the loss of the empire 's richest provinces , coupled with successive invasions , had reduced the imperial economy to a relatively impoverished state , compared to the resources available to the neighboring arab muslim empires . the byzantine government and military had been restructured , and the culture of the empire changed , too . as of heraclius ’ reign , greek replaced latin as the official language . instead of an urbanized , cosmopolitan civilization , the byzantine empire became an agrarian , military-dominated society caught up in a lengthy struggle with its neighbors . between the ninth and the eleventh century , the byzantine empire went on the offensive against its enemies and expanded its territory , conquering crete , cyprus , and most of syria . this period saw the conversion of the bulgarians , serbs , and rus to orthodox christianity , permanently changing the religious map of europe and the face of the byzantine empire . throughout this period , there was great competition among nobles for land in the theme system . since landowners could collect taxes and control the military forces of their themes , they became independent of the emperors and acted independently . this weakened the authority of the emperors . landowners tended to increase taxes on small farmers in order to enrich themselves . these increased taxes caused riots and further destabilized an already weakened order . though the situation seemed bleak , the byzantine empire survived into the fifteenth century , undergoing more transformations . however , the empire incurred significant territorial losses , and by the time the ottomans conquered constantinople , the byzantine empire was little more than constantinople itself .
|
two of these changes were the new capital at byzantium and the new christian character of the empire ( constantine legalized christianity and eventually converted himself ) . these changes eventually created a distinct culture which would characterize the byzantine empire after the fall of the western roman empire in 476 . even so , people living under the byzantine empire continued to see themselves as romans and continued to refer to their empire as the roman empire ; the terms byzantine empire and eastern roman empire were created much later . even though the byzantine empire is considered to start with constantine 's moving the capital to byzantium , it was not considered a separate empire by historians until the fall of the western roman empire in 476 .
|
how long did the byzantine empire and the roman empire grew together ?
|
overview the byzantine empire was the eastern continuation of the roman empire after the western roman empire 's fall in the fifth century ce . it lasted from the fall of the roman empire until the ottoman conquest in 1453 . continuities : the byzantine empire initially maintained many roman systems of governance and law and aspects of roman culture . the byzantines called themselves `` roman '' . the term `` byzantine empire '' was not used until well after the fall of the empire . changes : the byzantine empire shifted its capital from rome to constantinople , changed the official religion to christianity , and changed the official language from latin to greek . from rome to byzantium the fall of the roman empire was a pivotal moment in world history . but we sometimes forget that part of the roman empire continued on . even though the western roman empire , which was centered around rome , collapsed , the eastern roman empire survived as the byzantine empire . the byzantine empire lasted for a millennium after the fall of the roman empire , ending with the ottoman conquests in 1453 . while the roman empire 's capital was rome ( for most of its history ) , the byzantine empire ’ s capital city was constantinople , which was previously called byzantium , and today is istanbul . the capital was well-positioned near active trade routes connecting east and west . constantinople was named after emperor constantine i , the first byzantine emperor . in this article , we 're going to look at some of the continuities between the roman empire and the byzantine empire . we 'll also examine some of the changes that occurred , transforming the eastern roman empire into the byzantine empire . the roman empire in the east transformed into the byzantine empire over time , so it 's pretty hard to neatly separate the histories of the two empires , but most scholars agree that emperor constantine 's reign was the start of the byzantine empire . constantine—who ruled from 324 ce to 337 ce—made some significant changes to the roman empire . two of these changes were the new capital at byzantium and the new christian character of the empire ( constantine legalized christianity and eventually converted himself ) . these changes eventually created a distinct culture which would characterize the byzantine empire after the fall of the western roman empire in 476 . even so , people living under the byzantine empire continued to see themselves as romans and continued to refer to their empire as the roman empire ; the terms byzantine empire and eastern roman empire were created much later . even though the byzantine empire is considered to start with constantine 's moving the capital to byzantium , it was not considered a separate empire by historians until the fall of the western roman empire in 476 . even during this overlap , the nature of the eastern and western halves of the empire began to diverge . in particular , the greek language became more and more important in the east relative to latin . in addition , constantine legalized christianity . however , this was still a period of transition . it was n't until later , under theodosius i—who ruled from 379 ce to 395 ce—that christianity became the official state religion of the roman empire ( both east and west ) . during constantine 's rule , there was a mix of christian and pagan elements . let 's look at this passage written by the historian timothy e. gregory : there can be no doubt that , from 312 ce onward , constantine favored the christian church and that he offered it considerable wealth . he clearly became deeply involved in the religious controversies of the age and he favored christians in the employ of the state . at the same time , constantine continued to hold the office of pontifex maximus ( chief priest of the state religion ) , and pagan symbols continued to appear on his coins , at least until 323 ce . the early byzantine state once the western roman empire fell to germanic conquerors in 476 ce , the eastern empire continued on as what historians would later refer to as the byzantine empire . the first truly strong byzantine emperor was justinian—who ruled the byzantine empire from 482 ce to 565 ce . he was able to reclaim much of the western empire during his reign . emperor justinian also built upon roman ideas when he put forth a unified roman legal code . prior to his reign , roman laws had differed from region to region and many contradicted one another . it was during justinian ’ s reign that many of the most notable buildings and works of art in the byzantine empire were completed . in constantinople , the hagia sophia was constructed under justinian ’ s orders . at the time , it was the largest church in the world . justinian also contributed to constantinople ’ s growth by creating trade routes linking the capital to major cities to the east and west . a changing empire even after justinian ’ s efforts to reunify the byzantine empire , reconquer territory , and institute reforms , the stability of the byzantine empire was at risk . attacks from neighboring groups—including the persians , slavs , arabs , and turkic steppe people—weakened the integrity of the empire . the empire also lacked revenues and struggled to keep up with mounting military expenses . emperor heraclius ’ —who ruled from 610 ce to 641 ce—responded to these threats with a new set of reforms . he restructured the military , paying for it by clamping down on corruption and increasing taxes . he also started putting less gold in coins so he could mint more of them , enabling him to pay more soldiers . despite these reforms , wars with the arabs and the slavs significantly damaged the byzantine empire and reduced its territory drastically . though the government organization had stayed very much the same since the time of the romans , the byzantine empire began to transform in more drastic ways in the aftermath of these devastating wars . how did it change ? let 's read this passage written by byzantine scholar robert browning : since the days of diocletian and constantine , at the turn of the third and fourth centuries , rigid separation of civil and military authority had been the rule . civilian governors of provinces had no authority over troops stationed in their area . army commanders had none over the civilian population . [ ... ] it was a system designed to keep generals from dabbling in politics and staging military coups , and it worked . but it was cumbersome , it depended on the cooperation of the governing bodies of cities , which had to undertake much of the execution of government policy , and it made coordination of military and civil policy slow and difficult . now that no region of the empire was safe from attack , something different was needed . [ ... ] territories still under byzantine control were formed into military districts under the command of a strategos ( army leader ) , who was responsible for all aspects of government , civil and military . [ ... ] these new military districts were called themes , a word whose primary connotation is that of a division of troops . in the passage , browning described the emergence of the theme system . during heraclius ' rule the byzantine empire switched from the provincial administration system to this new system . under the theme system , land was granted to farmers who , in return , provided the empire with loyal soldiers . each district was called a theme . the efficiency of this system allowed the empire to keep hold of asia minor . the previous system of provinces was a civil administration , but the theme system fused civil administration with military administration . this system was fairly successful . because there was not enough money to pay soldiers , land grants were able to subsidize the military . also , soldiers had a personal stake in the land since it was their own . by the early eighth century , the byzantine empire began to look very different from the roman empire . the loss of the empire 's richest provinces , coupled with successive invasions , had reduced the imperial economy to a relatively impoverished state , compared to the resources available to the neighboring arab muslim empires . the byzantine government and military had been restructured , and the culture of the empire changed , too . as of heraclius ’ reign , greek replaced latin as the official language . instead of an urbanized , cosmopolitan civilization , the byzantine empire became an agrarian , military-dominated society caught up in a lengthy struggle with its neighbors . between the ninth and the eleventh century , the byzantine empire went on the offensive against its enemies and expanded its territory , conquering crete , cyprus , and most of syria . this period saw the conversion of the bulgarians , serbs , and rus to orthodox christianity , permanently changing the religious map of europe and the face of the byzantine empire . throughout this period , there was great competition among nobles for land in the theme system . since landowners could collect taxes and control the military forces of their themes , they became independent of the emperors and acted independently . this weakened the authority of the emperors . landowners tended to increase taxes on small farmers in order to enrich themselves . these increased taxes caused riots and further destabilized an already weakened order . though the situation seemed bleak , the byzantine empire survived into the fifteenth century , undergoing more transformations . however , the empire incurred significant territorial losses , and by the time the ottomans conquered constantinople , the byzantine empire was little more than constantinople itself .
|
justinian also contributed to constantinople ’ s growth by creating trade routes linking the capital to major cities to the east and west . a changing empire even after justinian ’ s efforts to reunify the byzantine empire , reconquer territory , and institute reforms , the stability of the byzantine empire was at risk . attacks from neighboring groups—including the persians , slavs , arabs , and turkic steppe people—weakened the integrity of the empire .
|
what were some of the ways the byzantine empire changed during justinian 's reign ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively .
|
should n't the k-component of the curl be perpendicular on the xy-plane ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard .
|
how do you make such beautiful animations ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) .
|
in the `` two dimensional fluid rotation revisited '' session , should the result `` 12-3=9 radians/second '' the twice of the angular velocity near that point ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) .
|
hidden `` why twice the angular speed ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated .
|
`` : does n't del v2 / del x give angular speed of particles left and right of ( x0 , y0 ) ( rather than above and below the point ) ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers .
|
what is the intuition behind this curl vector ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point .
|
do n't the particles rotate with respect to the i and j components in these examples ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated .
|
how do we get angular velocity in radians/second if we have n't parametrized the vector-valued function ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space .
|
in other words , if we do n't have a time component , how do we know the speed of the rotation at any given moment ?
|
background partial derivatives vector fields cross product curl warmup note : throughout this article i will use the convention that $ \hat { \textbf { i } } $ represents the unit vector in the $ x $ -direction . $ \hat { \textbf { j } } $ represents the unit vector in the $ y $ -direction . $ \hat { \textbf { k } } $ represents the unit vector in the $ z $ -direction . what we 're building to curl is an operator which takes in a function representing a three-dimensional vector field and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity . a positive angular velocity indicates a counter-clockwise rotation while a negative number indicates a clockwise rotation . the absolute value of the angular velocity gives the speed of rotation , typically in radians per second . for an object rotating in three dimensions , the situation is more complicated . we need to represent both angular velocity and the direction in three-dimensional space in which the object is rotating . to do this , rotation in three dimensions is typically described using a single vector . the magnitude of the vector indicates the angular speed , and the direction is determined by a super-important convention called the `` right-hand rule '' right-hand rule : curl the fingers of your right hand in the direction of rotation , and stick out your thumb . the vector representing this three-dimensional rotation is , by definition , oriented in the direction of your thumb . your thumb should point along the axis of rotation . adopting the convention of using the right hand instead of the left lets us encode the difference between a certain three-dimensional rotation , and the reverse rotation . basically , it extends the idea of clockwise vs. counterclockwise into three dimensions . for example , the rotation of the earth in space would be described using a vector pointing from the center of the earth to its north pole , whose length is equal to the angular speed of the earth 's rotation ( which happens to be $ 0.0000729 $ radians/second ) . two-dimensional fluid rotation revisited in the curl warmup article , i introduce how fluid flows along a two-dimensional vector field defined by the function $ \begin { align } \quad \vec { \textbf { v } } ( x , y ) & amp ; = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \end { array } \right ] \ & amp ; = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } \end { align } $ the following animation gives a simulation of this , where fluid particles ( drawn as blue dots ) always move in the direction of the vector they are closest to . for the purposes of studying curl , notice what happens in and around the circled regions . the fluid rotates counterclockwise in the left and right circles , and clockwise in the top and bottom circles . in studying curl , the key question is this : how much does the fluid rotate around each specific point $ ( x_0 , y_0 ) $ in the plane ? in the last article , i gave an intuition for how the answer to this question is what you might call the 2d-curl of $ \vec { \textbf { v } } $ , which has the following formula : $ \begin { align } \quad \text { 2d-curl } \ ; \vec { \textbf { v } } ( x_0 , y_0 ) = \dfrac { \partial \rede { v_2 } } { \bluee { \partial x } } ( x_0 , y_0 ) - \dfrac { \partial \bluee { v_1 } } { \rede { \partial y } } ( x_0 , y_0 ) \end { align } $ here , $ \bluee { v_1 } $ and $ \rede { v_2 } $ are the components of the vector-valued function $ \vec { \textbf { v } } $ . for example , with specific vector field given above , defined by $ ( { y^3 - 9y } ) \hat { \textbf { i } } + ( { x^3 - 9x } ) \hat { \textbf { j } } $ , this answer would be $ \begin { align } \quad \dfrac { \partial ( { x^3-9x } ) } { \partial x } - \dfrac { \partial ( { y^3-9y } ) } { \partial y } & amp ; = 3x^2 - 9 - ( 3y^2-9 ) \ & amp ; = 3x^2-3y^2 \end { align } $ notice , the result is a scalar-valued function . you plug in a point , like $ ( { 2 } , { 1 } ) $ , and you get out a single number which indicates angular velocity of the fluid near your point , $ 3 ( { 2 } ) ^2 - 3 ( { 1 } ) ^2 = 12-3 = 9 $ . as it turns out this number represents twice the angular speed of the fluid near the point , so the speed of rotation is $ 4.5 $ radians/second ( more on this later ) . the important point that you get a single scalar describing the rotation . this should make sense because the rotation of a single object in two dimensions can be described with a single number ( or scalar ) , so rotation around all possible points in a flowing fluid should be described with a scalar-valued function . reflection question : in the fluid flow animated above , does the fluid have a rotational component at the origin $ ( 0 , 0 ) $ ? moving to three dimensions in preparation for moving to three dimensions , let 's express the fluid rotation above using vectors . focus on a region of counterclockwise rotation , such as the right-most circle in the animation above . imagine wrapping your fingers around this circle , so they point in the direction of the arrows ( counterclockwise in this case ) , and stick out your thumb . your thumb should be pointing out of the page , in the positive $ z $ -direction , parallel to the unit vector $ \hat { \textbf { k } } $ . if we did this at every point , assigning a vector to the rotation around each point on the $ xy $ -plane according to the formula $ \text { 2d-curl } \ , \vec { \textbf { v } } ( x , y ) = 3x^2 - 3y^2 $ , you would end up with something like this : vectors pointing in the positive $ z $ -direction indicate counterclockwise rotation near that point , and vectors pointing the other way indicate clockwise rotation , as viewed from above the $ xy $ -plane . the length of each vector indicates the speed of that rotation . you could describe this system of vectors with the expression $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is almost a three-dimensional vector field , except that we are only looking at points on the $ xy $ -plane , not in all of space . curl itself only applies to three-dimensional vector fields , so to properly set the stage for the material below , let 's make this a fully three-dimensional example . to start , we extend our original vector-valued function $ \vec { \textbf { v } } $ to a similar three-dimensional function $ \vec { \textbf { v } } _ { 3d } $ . $ \begin { align } \quad \vec { \textbf { v } } _ { 3d } ( x , y , z ) = \left [ \begin { array } { c } \bluee { y^3 - 9y } \ \rede { x^3 - 9x } \ \greene { 0 } \end { array } \right ] = ( \bluee { y^3 - 9y } ) \hat { \textbf { i } } + ( \rede { x^3 - 9x } ) \hat { \textbf { j } } + ( \greene { 0 } ) \hat { \textbf { k } } \end { align } $ as three-dimensional vector fields go , this still feels very flat , does n't it ? the $ \hat { \textbf { k } } $ component is $ 0 $ everywhere , and none of the components depend on the $ z $ input variable at all . we have basically just copied the original two-dimensional vector field onto every slice of three-dimensional space parallel to the $ xy $ -plane . the next video shows what that vector field $ \vec { \textbf { v } } _ { 3d } $ looks like , where we keep the flat $ xy $ -plane ( drawn in grey ) and red circles as reference points . notice that at each layer parallel to the $ xy $ -plane , the vectors are identical to the original vectors we had sitting in the $ xy $ -plane from the purely 2d vector field $ \vec { \textbf { v } } $ in the previous section . again , imagine this vector field as representing a fluid flow , like air in a room or water in a pool . when we represent the rotation of this fluid around each point with a vector attached to that point , we get a new vector field , as shown in the next video : this is given by the vector-valued function $ \vec { \textbf { w } } ( x , y , z ) = ( 0 ) \hat { \textbf { i } } + ( 0 ) \hat { \textbf { j } } + ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ this is the same formula that we had before , $ ( 3x^2 - 3y^2 ) \hat { \textbf { k } } $ , but the important point is that now we apply it to all points $ ( x , y , z ) $ in space , not just the points $ ( x , y ) $ in the $ xy $ -plane . the fact that the $ z $ -input does not influence the output reflects the fact that our fluid motion is the same in all slices of space parallel to the $ xy $ -plane . the fact that the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components are $ 0 $ means all rotation vectors point purely in the $ z $ -direction , meaning all actual fluid rotation is parallel to the $ xy $ -plane . this new ( blue ) vector field $ \vec { \textbf { w } } $ is called the `` curl '' of the initial ( green ) vector field $ \vec { \textbf { v } } _ { 3d } $ . one way you might see this written is $ \begin { align } \quad \vec { \textbf { w } } = \text { curl } \ , \vec { \textbf { v } } _ { 3d } \end { align } $ this is our first example of honest-to-goodness three-dimensional curl : curl , as a mathematical operator , takes in a three-dimensional vector-valued function $ \vec { \textbf { v } } { 3d } $ , thought of as representing a fluid flow , and outputs another three-dimensional vector-valued function `` $ \text { curl } \ , \vec { \textbf { v } } { 3d } $ '' which represents the rotation near each point of that fluid . visualizing fluid rotation in three dimensions for a general fluid flow in three dimensions , the rotation may not always be purely parallel to the $ xy $ -plane . this can make it hard to picture what 's going on . really hard . for instance , imagine that the air around you is blowing and swirling in some chaotic motion . now pick some specific point $ ( x_0 , y_0 , z_0 ) $ in space . how can you think about what `` air rotation near that point '' means ? here are a couple of tactics : imagine there is a tiny tennis ball whose center is fixed to the point $ ( x_0 , y_0 , z_0 ) $ , but which is free to rotate . perhaps you have invented magic to hold it there , or otherwise have some sort of ingenious magnetic suspension device . the air blowing around it may cause it to spin in some way or another . the curl vector attached to that point will be the vector describing this tiny tennis ball 's rotation , in the same way , we described the earth 's rotation using a single vector above . alternatively , take an archer 's arrow with nice thick feathers . the kind you might imagine robin hood shooting . situate the arrow in midair such that its feathers are at the point $ ( x_0 , y_0 , z_0 ) $ . again , you 've invented magic and finagle a way so that the base of the arrow is fixed to this point , but you are free to orient the arrow in any direction you want , and it freely rotates based on how the wind blows its feathers . if you experiment with various orientations for the arrow and find the one direction in which the air currents cause the arrow to rotate the fastest , this is the direction of the curl vector at the point $ ( x_0 , y_0 , z_0 ) $ . this is somewhat analogous to how the gradient points in the `` direction of steepest ascent '' ; the curl points in the `` direction of greatest rotation '' . notation and formula for curl let 's write $ \vec { \textbf { v } } $ as a general vector-valued function , with three inputs $ ( x , y , z ) $ and a three-coordinate output . we will write this three-coordinate output in terms of three scalar valued functions : $ \bluee { v_1 ( x , y , z ) } $ , $ \rede { v_2 ( x , y , z ) } $ , and $ \greene { v_3 ( x , y , z ) } $ . $ \begin { align } \quad \vec { \textbf { v } } ( x , y , z ) & amp ; = \left [ \begin { array } { c } \bluee { v_1 ( x , y , z ) } \ \rede { v_2 ( x , y , z ) } \ \greene { v_3 ( x , y , z ) } \end { array } \right ] \\ & amp ; = \bluee { v_1 ( x , y , z ) } \hat { \textbf { i } } + \rede { v_2 ( x , y , z ) } \hat { \textbf { j } } + \greene { v_3 ( x , y , z ) } \hat { \textbf { k } } \end { align } $ the notation for curl uses the same symbol `` $ \nabla $ '' used in the expressions for gradient and divergence , and once again we think of it as representing a vector of partial derivative operators : $ \begin { align } \quad \nabla = \left [ \begin { array } { c } \ \dfrac { \partial } { \partial x } \ \ \dfrac { \partial } { \partial y } \ \ \dfrac { \partial } { \partial z } \ \ \end { array } \right ] \end { align } $ the curl is thought of as the cross product of this `` vector '' and the function $ \vec { \textbf { v } } $ , computed using the determinant as usual : i know what you 're thinking : `` that 's the funkiest determinant i 've ever seen . none of the elements are even numbers ! one row has vectors , one has operators , and one has functions . can you even do that ? '' it 's a bit weird , sure , but it works as a notational trick if nothing else . intuition for the formula let 's take a close look at this final result : notice , each component is like its own version of $ \text { 2d-curl } $ operator we found in the curl warm up article . in fact , the $ \vec { \textbf { k } } $ component has precisely the same formula as the $ \text { 2d-curl } $ . this should make sense because the $ \vec { \textbf { k } } $ -component of curl should measure the component of fluid rotation which is parallel to the $ xy $ -plane . likewise , the $ \hat { \textbf { i } } $ and $ \hat { \textbf { j } } $ components measure the component of the fluid rotation parallel to the $ yz $ and $ xz $ planes respectively . one little nuance i should point out is that when you evaluate the curl near a point to get a vector ( thought of as a rotation vector ) , the magnitude of that vector does not equal the angular speed of the imagined fluid near that point . instead the magnitude is equal to twice the angular speed of the fluid . example : finding rotation in a three-dimensional vector field using curl problem : suppose a fluid flows in three dimensions according to the following vector field $ \vec { \textbf { v } } ( x , y , z ) = ( \bluee { x^3 + y^2 + z } ) \hat { \textbf { i } } + ( \rede { ze^x } ) \hat { \textbf { j } } + ( \greene { xyz-9xz } ) \hat { \textbf { k } } $ describe the rotation of the fluid near the point $ ( 0 , 1 , 2 ) $ step 1 : evaluate curl ( you may want some paper for this one ) . step 2 : plug in $ ( 0 , 1 , 2 ) $ step 3 : interpret summary curl is an operator which takes in a function representing a three-dimensional vector field , and gives another function representing a different three-dimensional vector field . if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by a half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component function $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \begin { align } \quad \nabla \times \vec { \textbf { v } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } \end { align } $ just for fun here 's an animation of the fluid flow i showed at the very start of the article , but this time each dot is treated more accurately like a droplet of water , flexing and twisting based on how the vector field pulls on each individual particle in the droplet . i also took away the actual vectors from the vector field so that it 's easier to see how the fluid moves . hopefully this gives an impression for how complex yet beautiful the fluid-flow conception of vector fields can be .
|
if a fluid flows in three-dimensional space along a vector field , the rotation of that fluid around each point , represented as a vector , is given by the curl of the original vector field evaluated at that point . the curl vector field should be scaled by one-half if you want the magnitude of curl vectors to equal the rotational speed of the fluid . if a three-dimensional vector-valued function $ \vec { \textbf { v } } ( x , y , z ) $ has component functions $ \bluee { v_1 } ( x , y , z ) $ , $ \rede { v_2 } ( x , y , z ) $ and $ \greene { v_3 } ( x , y , z ) $ , the curl is computed as follows : $ \underbrace { \nabla \times \vec { \textbf { v } } } _ { \text { notation for curl } } = \left ( \dfrac { \partial \greene { v_3 } } { \partial y } - \dfrac { \partial \rede { v_2 } } { \partial z } \right ) \hat { \textbf { i } } + \left ( \dfrac { \partial \bluee { v_1 } } { \partial z } - \dfrac { \partial \greene { v_3 } } { \partial x } \right ) \hat { \textbf { j } } + \left ( \dfrac { \partial \rede { v_2 } } { \partial x } - \dfrac { \partial \bluee { v_1 } } { \partial y } \right ) \hat { \textbf { k } } $ describing rotation with a vector if an object is rotating in two dimensions , you can describe the rotation completely with a single number : the angular velocity .
|
or does curl just give us rotational speed relative to other points in the field ?
|
overview bill clinton was the 42nd president of the united states . he was elected in 1992 and reelected in 1996 , becoming the first democratic president since franklin d. roosevelt to serve two terms in office . clinton came to the white house with an ambitious domestic policy agenda centered on economic growth and immediately took steps to reduce the federal budget deficit . clinton ’ s second term was marred by scandal , as he was impeached for lying to congress and the american people about an extramarital affair with white house intern monica lewinsky . despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era . bill clinton ’ s rise to power bill clinton was born william jefferson blythe iii in hope , arkansas in 1946 but formally adopted his stepfather ’ s surname , clinton , when he was fifteen years old . he attended georgetown university and was a rhodes scholar at oxford before going on to earn his law degree at yale . he served one term as attorney general of the state of arkansas and was elected governor in 1978 . frequently referred to as the “ boy governor ” because of his young age ( he was 32 years old ) , clinton enacted reforms in the areas of education , welfare , and healthcare . he was reelected in 1982 and became a leader of the new democrats , a centrist wing of the democratic party that sought to decrease the size and scope of the federal government—a goal to which progressives and liberals were vehemently opposed . in 1992 , he secured the democratic party ’ s presidential nomination , and won in a three-way race against incumbent president george h.w . bush , a republican , and independent third-party candidate ross perot . clinton was the first us president from the baby boomer generation . he was reelected in 1996 , becoming the first democrat since franklin d. roosevelt to serve two terms as president . he is married to hillary rodham clinton , who represented the state of new york in the us senate before becoming secretary of state during the obama administration . clinton ’ s first term ( 1993-1997 ) bill clinton came to the white house with an ambitious domestic agenda centered on economic growth . he immediately set to work reducing the federal budget deficit . the omnibus budget reconciliation act of 1993 , known unofficially as the deficit reduction act of 1993 , raised taxes for the wealthiest 1.2 percent , while cutting taxes for small businesses and lower-income wage earners . the legislation included a requirement to balance the federal budget , and set the stage for an economic resurgence that culminated in a federal budget surplus . the clinton administration proved less successful in the realm of healthcare reform . although implementing a national health care plan with universal coverage was a top priority for clinton , opposition from republicans , the american medical association , and the health insurance industry proved an insurmountable obstacle to healthcare reform . on january 1 , 1994 , president clinton signed into law the north american free trade agreement ( nafta ) , which eliminated barriers to trade and investment between the united states , canada , and mexico . though some have criticized nafta for moving jobs out of the united states , the overall economic impact of the agreement has been mostly beneficial , not only for the united states , but for canada and mexico as well . the gross domestic product ( gdp ) of all three countries grew as a direct result of nafta , while trade and investment flourished and some industries that were expected to decline instead thrived as never before. $ ^1 $ clinton ’ s second term ( 1997-2001 ) although bill clinton easily won reelection in 1996 , his second term in office was marred by corruption and scandal . clinton became the second president in us history to be impeached , after he was discovered to have lied to congress and the american people about his involvement in an extramarital affair with white house intern monica lewinsky . though the house of representatives charged clinton with perjury and obstruction of justice , the senate vote , which was largely along party lines , did not attain the two-thirds majority required by the us constitution to remove him from office. $ ^2 $ despite the scandal , clinton left the white house with the highest approval rating of any us president in the post-world war ii era. $ ^3 $ he was succeeded in office by george w. bush . what do you think ? what were clinton ’ s greatest achievements as president ? what were his biggest shortcomings ? why do you think clinton continued to enjoy such great popularity even after the monica lewinsky scandal ? overall , how would you rate bill clinton ’ s performance as president ?
|
the clinton administration proved less successful in the realm of healthcare reform . although implementing a national health care plan with universal coverage was a top priority for clinton , opposition from republicans , the american medical association , and the health insurance industry proved an insurmountable obstacle to healthcare reform . on january 1 , 1994 , president clinton signed into law the north american free trade agreement ( nafta ) , which eliminated barriers to trade and investment between the united states , canada , and mexico .
|
why did republicans oppose the new health care plan clinton wanted to propose ?
|
overview bill clinton was the 42nd president of the united states . he was elected in 1992 and reelected in 1996 , becoming the first democratic president since franklin d. roosevelt to serve two terms in office . clinton came to the white house with an ambitious domestic policy agenda centered on economic growth and immediately took steps to reduce the federal budget deficit . clinton ’ s second term was marred by scandal , as he was impeached for lying to congress and the american people about an extramarital affair with white house intern monica lewinsky . despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era . bill clinton ’ s rise to power bill clinton was born william jefferson blythe iii in hope , arkansas in 1946 but formally adopted his stepfather ’ s surname , clinton , when he was fifteen years old . he attended georgetown university and was a rhodes scholar at oxford before going on to earn his law degree at yale . he served one term as attorney general of the state of arkansas and was elected governor in 1978 . frequently referred to as the “ boy governor ” because of his young age ( he was 32 years old ) , clinton enacted reforms in the areas of education , welfare , and healthcare . he was reelected in 1982 and became a leader of the new democrats , a centrist wing of the democratic party that sought to decrease the size and scope of the federal government—a goal to which progressives and liberals were vehemently opposed . in 1992 , he secured the democratic party ’ s presidential nomination , and won in a three-way race against incumbent president george h.w . bush , a republican , and independent third-party candidate ross perot . clinton was the first us president from the baby boomer generation . he was reelected in 1996 , becoming the first democrat since franklin d. roosevelt to serve two terms as president . he is married to hillary rodham clinton , who represented the state of new york in the us senate before becoming secretary of state during the obama administration . clinton ’ s first term ( 1993-1997 ) bill clinton came to the white house with an ambitious domestic agenda centered on economic growth . he immediately set to work reducing the federal budget deficit . the omnibus budget reconciliation act of 1993 , known unofficially as the deficit reduction act of 1993 , raised taxes for the wealthiest 1.2 percent , while cutting taxes for small businesses and lower-income wage earners . the legislation included a requirement to balance the federal budget , and set the stage for an economic resurgence that culminated in a federal budget surplus . the clinton administration proved less successful in the realm of healthcare reform . although implementing a national health care plan with universal coverage was a top priority for clinton , opposition from republicans , the american medical association , and the health insurance industry proved an insurmountable obstacle to healthcare reform . on january 1 , 1994 , president clinton signed into law the north american free trade agreement ( nafta ) , which eliminated barriers to trade and investment between the united states , canada , and mexico . though some have criticized nafta for moving jobs out of the united states , the overall economic impact of the agreement has been mostly beneficial , not only for the united states , but for canada and mexico as well . the gross domestic product ( gdp ) of all three countries grew as a direct result of nafta , while trade and investment flourished and some industries that were expected to decline instead thrived as never before. $ ^1 $ clinton ’ s second term ( 1997-2001 ) although bill clinton easily won reelection in 1996 , his second term in office was marred by corruption and scandal . clinton became the second president in us history to be impeached , after he was discovered to have lied to congress and the american people about his involvement in an extramarital affair with white house intern monica lewinsky . though the house of representatives charged clinton with perjury and obstruction of justice , the senate vote , which was largely along party lines , did not attain the two-thirds majority required by the us constitution to remove him from office. $ ^2 $ despite the scandal , clinton left the white house with the highest approval rating of any us president in the post-world war ii era. $ ^3 $ he was succeeded in office by george w. bush . what do you think ? what were clinton ’ s greatest achievements as president ? what were his biggest shortcomings ? why do you think clinton continued to enjoy such great popularity even after the monica lewinsky scandal ? overall , how would you rate bill clinton ’ s performance as president ?
|
clinton came to the white house with an ambitious domestic policy agenda centered on economic growth and immediately took steps to reduce the federal budget deficit . clinton ’ s second term was marred by scandal , as he was impeached for lying to congress and the american people about an extramarital affair with white house intern monica lewinsky . despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era .
|
why was andrew johnson impeached ?
|
overview bill clinton was the 42nd president of the united states . he was elected in 1992 and reelected in 1996 , becoming the first democratic president since franklin d. roosevelt to serve two terms in office . clinton came to the white house with an ambitious domestic policy agenda centered on economic growth and immediately took steps to reduce the federal budget deficit . clinton ’ s second term was marred by scandal , as he was impeached for lying to congress and the american people about an extramarital affair with white house intern monica lewinsky . despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era . bill clinton ’ s rise to power bill clinton was born william jefferson blythe iii in hope , arkansas in 1946 but formally adopted his stepfather ’ s surname , clinton , when he was fifteen years old . he attended georgetown university and was a rhodes scholar at oxford before going on to earn his law degree at yale . he served one term as attorney general of the state of arkansas and was elected governor in 1978 . frequently referred to as the “ boy governor ” because of his young age ( he was 32 years old ) , clinton enacted reforms in the areas of education , welfare , and healthcare . he was reelected in 1982 and became a leader of the new democrats , a centrist wing of the democratic party that sought to decrease the size and scope of the federal government—a goal to which progressives and liberals were vehemently opposed . in 1992 , he secured the democratic party ’ s presidential nomination , and won in a three-way race against incumbent president george h.w . bush , a republican , and independent third-party candidate ross perot . clinton was the first us president from the baby boomer generation . he was reelected in 1996 , becoming the first democrat since franklin d. roosevelt to serve two terms as president . he is married to hillary rodham clinton , who represented the state of new york in the us senate before becoming secretary of state during the obama administration . clinton ’ s first term ( 1993-1997 ) bill clinton came to the white house with an ambitious domestic agenda centered on economic growth . he immediately set to work reducing the federal budget deficit . the omnibus budget reconciliation act of 1993 , known unofficially as the deficit reduction act of 1993 , raised taxes for the wealthiest 1.2 percent , while cutting taxes for small businesses and lower-income wage earners . the legislation included a requirement to balance the federal budget , and set the stage for an economic resurgence that culminated in a federal budget surplus . the clinton administration proved less successful in the realm of healthcare reform . although implementing a national health care plan with universal coverage was a top priority for clinton , opposition from republicans , the american medical association , and the health insurance industry proved an insurmountable obstacle to healthcare reform . on january 1 , 1994 , president clinton signed into law the north american free trade agreement ( nafta ) , which eliminated barriers to trade and investment between the united states , canada , and mexico . though some have criticized nafta for moving jobs out of the united states , the overall economic impact of the agreement has been mostly beneficial , not only for the united states , but for canada and mexico as well . the gross domestic product ( gdp ) of all three countries grew as a direct result of nafta , while trade and investment flourished and some industries that were expected to decline instead thrived as never before. $ ^1 $ clinton ’ s second term ( 1997-2001 ) although bill clinton easily won reelection in 1996 , his second term in office was marred by corruption and scandal . clinton became the second president in us history to be impeached , after he was discovered to have lied to congress and the american people about his involvement in an extramarital affair with white house intern monica lewinsky . though the house of representatives charged clinton with perjury and obstruction of justice , the senate vote , which was largely along party lines , did not attain the two-thirds majority required by the us constitution to remove him from office. $ ^2 $ despite the scandal , clinton left the white house with the highest approval rating of any us president in the post-world war ii era. $ ^3 $ he was succeeded in office by george w. bush . what do you think ? what were clinton ’ s greatest achievements as president ? what were his biggest shortcomings ? why do you think clinton continued to enjoy such great popularity even after the monica lewinsky scandal ? overall , how would you rate bill clinton ’ s performance as president ?
|
despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era . bill clinton ’ s rise to power bill clinton was born william jefferson blythe iii in hope , arkansas in 1946 but formally adopted his stepfather ’ s surname , clinton , when he was fifteen years old . he attended georgetown university and was a rhodes scholar at oxford before going on to earn his law degree at yale .
|
did bill clinton have ideas similar to those of the new democrats , or did he just make an appeal to the new democrats to get their vote ?
|
overview bill clinton was the 42nd president of the united states . he was elected in 1992 and reelected in 1996 , becoming the first democratic president since franklin d. roosevelt to serve two terms in office . clinton came to the white house with an ambitious domestic policy agenda centered on economic growth and immediately took steps to reduce the federal budget deficit . clinton ’ s second term was marred by scandal , as he was impeached for lying to congress and the american people about an extramarital affair with white house intern monica lewinsky . despite the lewinsky affair , clinton left the white house with the highest approval rating of any us president in the post-world war ii era . bill clinton ’ s rise to power bill clinton was born william jefferson blythe iii in hope , arkansas in 1946 but formally adopted his stepfather ’ s surname , clinton , when he was fifteen years old . he attended georgetown university and was a rhodes scholar at oxford before going on to earn his law degree at yale . he served one term as attorney general of the state of arkansas and was elected governor in 1978 . frequently referred to as the “ boy governor ” because of his young age ( he was 32 years old ) , clinton enacted reforms in the areas of education , welfare , and healthcare . he was reelected in 1982 and became a leader of the new democrats , a centrist wing of the democratic party that sought to decrease the size and scope of the federal government—a goal to which progressives and liberals were vehemently opposed . in 1992 , he secured the democratic party ’ s presidential nomination , and won in a three-way race against incumbent president george h.w . bush , a republican , and independent third-party candidate ross perot . clinton was the first us president from the baby boomer generation . he was reelected in 1996 , becoming the first democrat since franklin d. roosevelt to serve two terms as president . he is married to hillary rodham clinton , who represented the state of new york in the us senate before becoming secretary of state during the obama administration . clinton ’ s first term ( 1993-1997 ) bill clinton came to the white house with an ambitious domestic agenda centered on economic growth . he immediately set to work reducing the federal budget deficit . the omnibus budget reconciliation act of 1993 , known unofficially as the deficit reduction act of 1993 , raised taxes for the wealthiest 1.2 percent , while cutting taxes for small businesses and lower-income wage earners . the legislation included a requirement to balance the federal budget , and set the stage for an economic resurgence that culminated in a federal budget surplus . the clinton administration proved less successful in the realm of healthcare reform . although implementing a national health care plan with universal coverage was a top priority for clinton , opposition from republicans , the american medical association , and the health insurance industry proved an insurmountable obstacle to healthcare reform . on january 1 , 1994 , president clinton signed into law the north american free trade agreement ( nafta ) , which eliminated barriers to trade and investment between the united states , canada , and mexico . though some have criticized nafta for moving jobs out of the united states , the overall economic impact of the agreement has been mostly beneficial , not only for the united states , but for canada and mexico as well . the gross domestic product ( gdp ) of all three countries grew as a direct result of nafta , while trade and investment flourished and some industries that were expected to decline instead thrived as never before. $ ^1 $ clinton ’ s second term ( 1997-2001 ) although bill clinton easily won reelection in 1996 , his second term in office was marred by corruption and scandal . clinton became the second president in us history to be impeached , after he was discovered to have lied to congress and the american people about his involvement in an extramarital affair with white house intern monica lewinsky . though the house of representatives charged clinton with perjury and obstruction of justice , the senate vote , which was largely along party lines , did not attain the two-thirds majority required by the us constitution to remove him from office. $ ^2 $ despite the scandal , clinton left the white house with the highest approval rating of any us president in the post-world war ii era. $ ^3 $ he was succeeded in office by george w. bush . what do you think ? what were clinton ’ s greatest achievements as president ? what were his biggest shortcomings ? why do you think clinton continued to enjoy such great popularity even after the monica lewinsky scandal ? overall , how would you rate bill clinton ’ s performance as president ?
|
what were his biggest shortcomings ? why do you think clinton continued to enjoy such great popularity even after the monica lewinsky scandal ? overall , how would you rate bill clinton ’ s performance as president ?
|
why did clinton enjoy such a high approval rating even though he was impeached ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become .
|
if i make a sketch today with charcoal my great-grandfather bought 100 years ago , does the age of the pigment change if i use it now ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) .
|
in terms of carbon-dating the pigment itself , is it not possible that the charcoal itself is 30,000 years old but the drawing is not ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) .
|
and how scientific is it to date a cave drawing based on the age of other artifacts found nearby or should n't that be considered more circumstantial ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
also , any idea on why the art is so well preserved ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction .
|
is it possible that those images in the caves might have represented plans or schedules and organized tasks in a way ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making .
|
as a native american i was wondering how old the oldest u.s. based painting or artform is and any idea from when and what people ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen .
|
are these paintings the same ones , that we can see in the movie cave of forgotten dreams ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e .
|
what can we learn about the values of prehistoric people by looking at the images they created ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame .
|
any speculation as to why the animal figures seem to be very accurate representations of the real thing , yet the human drawings are stick-like and much less realistic ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
what could we take from roman art and other ancient civilzations arts to interpt art like this ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy .
|
in the last paragraph , why is the cave littered with skulls , bones and tracks ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined .
|
could it be possible that the overlapping horses represent a herd of horses on the run ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading .
|
also it seems a chaotic scene as if there is a giant stampede with animals retreating from something perhaps a fire ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
how long did this take to make the website and did u get these facts from wikipedia ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre .
|
since all people migrated out of africa and eventually found themselves trying to adapt to new climates and terrains -- is it possible that they retained mythic or ancestral memories of important animals and traditions ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
honey bees could not survive an ice age , but maybe their memory lived on in art ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
is it true that a foot-print was made by an eight year old boy in the cave ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf .
|
i also wonder why these prehistoric people did n't draw images to themselves ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen .
|
when i look at cave paintings i can see these people had wonderful skills , buy why they did n't draw any kind of portraits ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves .
|
what needs are the visual arts believed to have first fulfilled in human culture ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) .
|
how did they take carbon samples and why ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading .
|
in the section on chauvet-pont-d'arc , when it says that scholars note these animals were not part of humans regular diet , were they referring to all the animals listed or just the owls ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction .
|
in caves how painters can get the material for drawing ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction .
|
how did explorers find `` the caves '' ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
what is the top picture supposed to be ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
who was the 8 year old boy ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken .
|
is there a way to visit the cave of chavet-pont-d'arch site/link in english ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e .
|
are there any archeological findings in other parts of the world that are comparable ( in regards to age and scope ) to lascaux ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
how was the art made ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
what is the oldest art piece in the whole world ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy .
|
how on earth did cave men in france know what a rhino and lion was ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious .
|
how were these paintings able to last such a long time does n't seem as if they 've even faded at all ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
seeing as prehistoric peoples made these intricate drawings , do you think they were more knowledgeable and sophisticated than as previously thought ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
so how did art exactly begin , did someone start drawing on the cave walls just to see how something works , or did people know how to draw already ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf .
|
also who was the first person to ever create a drawing ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
dr. randell white was suggesting that the artwork was sequential art depicting the life of the horse ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
why do you take such a western art approach ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading .
|
not a question , just a spelling correction : megaceros deer should be megaloceros deer , right ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us .
|
you forgot to mention petroglyphs in gobustan ( azerbaijan ) https : //en.wikipedia.org/wiki/gobustan_national_park # /media/file : ancient_azerbaijan_4.jpg http : //whc.unesco.org/en/list/1076 or are n't they relevant ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf .
|
maybe they drew the thighs and genitals of a woman for showing respect of social status of female at that time ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction .
|
would the repetitions made in the caves perhaps reflect back on the spiritual life of the artist/community ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy .
|
could the same be true of the cave paintings ?
|
the oldest art : ornamentation humans make art . we do this for many reasons and with whatever technologies are available to us . extremely old , non-representational ornamentation has been found across africa . the oldest firmly-dated example is a collection of 82,000 year old nassarius snail shells found in morocco that are pierced and covered with red ochre . wear patterns suggest that they may have been strung beads . nassarius shell beads found in israel may be more than 100,000 years old and in the blombos cave in south africa , pierced shells and small pieces of ochre ( red haematite ) etched with simple geometric patterns have been found in a 75,000-year-old layer of sediment . the oldest representational art the oldest known representational imagery comes from the aurignacian culture of the upper paleolithic period ( paleolithic means old stone age ) . archeological discoveries across a broad swath of europe ( especially southern france , northern spain , and swabia , in germany ) include over two hundred caves with spectacular aurignacian paintings , drawings and sculpture that are among the earliest undisputed examples of representational image-making . the oldest of these is a 2.4-inch tall female figure carved out of mammoth ivory that was found in six fragments in the hohle fels cave near schelklingen in southern germany . it dates to 35,000 b.c.e . the caves the caves at chauvet-pont-d'arc , lascaux , pech merle , and altamira contain the best known examples of pre-historic painting and drawing . here are remarkably evocative renderings of animals and some humans that employ a complex mix of naturalism and abstraction . archeologists that study paleolithic era humans , believe that the paintings discovered in 1994 , in the cave at chauvet-pont-d'arc in the ardéche valley in france , are more than 30,000 years old . the images found at lascaux and altamira are more recent , dating to approximately 15,000 b.c.e . the paintings at pech merle date to both 25,000 and 15,000 b.c.e . questions what can we really know about the creators of these paintings and what the images originally meant ? these are questions that are difficult enough when we study art made only 500 years ago . it is much more perilous to assert meaning for the art of people who shared our anatomy but had not yet developed the cultures or linguistic structures that shaped who we have become . do the tools of art history even apply ? here is evidence of a visual language that collapses the more than 1,000 generations that separate us , but we must be cautious . this is especially so if we want to understand the people that made this art as a way to understand ourselves . the desire to speculate based on what we see and the physical evidence of the caves is wildly seductive . chauvet-pont-d'arc the cave at chauvet-pont-d'arc is over 1,000 feet in length with two large chambers . carbon samples date the charcoal used to depict the two head-to-head rhinoceroses ( see the image above , bottom right ) to between 30,340 and 32,410 years before 1995 when the samples were taken . the cave 's drawings depict other large animals including horses , mammoths , musk ox , ibex , reindeer , aurochs , megaloceros deer , panther , and owl ( scholars note that these animals were not then a normal part of people 's diet ) . photographs show that the drawing shown above is very carefully rendered but may be misleading . we see a group of horses , rhinos and bison and we see them as a group , overlapping and skewed in scale . but the photograph distorts the way these animal figures would have been originally seen . the bright electric lights used by the photographer create a broad flat scope of vision ; how different to see each animal emerge from the dark under the flickering light cast by a flame . a word of caution in a 2009 presentation at uc san diego , dr. randell white , professor of anthropology at nyu , suggested that the overlapping horses pictured above might represent the same horse over time , running , eating , sleeping , etc . perhaps these are far more sophisticated representations than we have imagined . there is another drawing at chauvet-pont-d'arc that cautions us against ready assumptions . it has been interpreted as depicting the thighs and genitals of a woman but there is also a drawing of a bison and a lion and the images are nearly intertwined . in addition to the drawings , the cave is littered with the skulls and bones of cave bear and the track of a wolf . there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
there is also a foot print thought to have been made by an eight-year-old boy . essay by dr. beth harris and dr. steven zucker additional resources : the cave of chauvet-pont-d'arc a carved female figurine dating to at least 35,000 years ago recovered from caves in the hohle fels region of germany ( video ) lascaux : a visit to the cave lascaux on the metropolitan museum of art 's heilbrunn timeline of art history `` ur-mothers '' in the new yorker
|
i have no proof , of course , but is it not at least possible that the german archaeologists unearthed an early form of humour ?
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.