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Coumadin® or Warfarin®, should be warned of the potential for bleeding: excessive bleeding can occur from even a seemingly benign ear or sinus barotrauma. There is a potential risk that, if decompression illness occurs, it may then cause significant bleeding |
in the brain or spinal cord Get in the Know Cardiovascular disease can contribute to dive injuries as well as fatalities. Both are preventable. With increased information about cardiovascular health and fitness, divers can make better choices and increase the |
opportunity that every dive will be accident- and injury-free. Read all you can about your medications, consult with your doctor, and when you have questions about diving and drugs, call DAN. (c) DAN - Alert Diver November / December 2005 |
|Effects of Inputs and Outputs on a Region| The purpose of this resource is to identify what enters and leaves the regional system, and how changes in the input or output of one component can affect other components. Intended for grade levels: Type of resource: Adobe Acrobat reader Cost / Copyright: For science/educati... |
THE FRAGILE FAUNA OF ILLINOIS CAVES by Steven J. Taylor and Donald W. Webb Illinois has several hundred caves, many of them in nearly pristine condition. This unique and fragile |
environment is home to a diverse array of creatures, including organisms that are completely limited to the cave environment, species that may be found in similar habitats above ground, and |
the many animals that accidentally wander, fall, or are washed into caves. Many cave animals are highly adapted for the unique and harsh living conditions they encounter underground. caves can |
be found in four distinct karst regions: in the Mississippian limestone of the Shawnee Hills, in the Salem Plateau and in the Lincoln Hills, and in the Ordovician limestone of |
the Driftless Area. These caves have been forming though the interaction of geology vegetation, and rainfall for the past 300 million years. Shallow seas covered much of Illinois during the |
Mississippian Period. When the seas receded, forests grew over the exposed sedimentary rocks; and rainwater-which had become slightly acidic through interaction with carbon dioxide from both the atmosphere and the |
bacterial breakdown of organic material-then seeped into cracks and bedding planes. As the limestone dissolved, conduits formed. These conduits eventually developed the geologic features characteristic of karst terrain-caves, sinking streams, |
springs, and sinkholes. INTO THE TWILIGHT ZONE Caves can be divided into three ecological zones. The entrance zone is similar in light, temperature, and relative humidity to the surrounding surface |
habitat, and the creatures that live there resemble the animals that live in the moist shaded areas near the cave. Hear we find the eastern phoebe (Sayornis phoebe), a small |
gray bird whose nest is constructed on bare bedrock walls out of mosses and other debris. In the leaf litter, we find many animals of the forest floor: redbacked salamanders, |
harvestmen (or daddy-longlegs), snails, earthworms, millipedes, centipedes, beetles, ants, and springtails. Cave entrances are often funnel shaped or have sheer vertical walls, and organisms and organic debris tend to concentrate |
at the bottom. The entrance zone also provides a highly protected environment for overwintering organisms. Deeper inside the cave, in the twilight zone, there is much less light, and photosynthesizing |
plants are no longer able to grow. The temperature and relative humidity fluctuate here, but the environment is usually damp and cool. Many animals from the entrance zone wander into |
the twilight zone, but most of these creatures must eventually return to the land above. Several species of cave crickets are common in this part of the cave, sometimes appearing |
in large numbers on walls or ceilings. In larger caves, there is a dark zone characterized by constant temperature (about 54-58*F in Illinois) and the absence of light. Here, the |
relative humidity approaches the saturation point. Many animals in the dark zone are capable of completing their entire life cycles without leaving the cave although food is scarce in the |
absence of photosynthesis. In this zone, there are fewer species of organisms. Creatures who live here eat primarily organic debris-wood, leaves, and accidental animals. Dark-zone dwellers get some of their |
nutrients from the feces of bats and cave crickets, animals that leave the cave at night to feed on the surface. Raccoons, common cave explorers in Illinois, also leave their |
waste behind. A wide array of bacteria and fungi feast upon these nutrient-rich items. Other animals then feed upon the fungi and bacteria. Springtails, minute insects typically overlooked by the |
casual observes, are important fungus feeders, and a variety of beetles, flies, and millipedes get their nourishment this way as well. These organisms may then become the prey of cave-inhabiting |
spiders, harvestmen, predacious fly larvae known as webworms, and an occasional cave salamander. In the winter, pickerel frogs, mosquitoes, and some moths move into cave to wait for warmer weather. |
ADAPTING AND SURVIVING Common Cave inhabitants include (left to right) the moth, Scoliopteryz libatrix, which does not have a comon name; the cave salamander (Eurycea lucifuga); and the monorail worm |
(Macrocera nonilis). Animals that live in caves vary greatly in their degree of adaptation to the cave environment. Accidental animals live there only temporarily; they will either leave or die. |
Animals that frequent cave but must return to the surface at some point in there life cycles are know as trogloxenes. Bats and cave crickets are two examples. Troglophiles are |
animals that can complete their entire life cycles within a cave, but they may also be found in cool, moist habitats outside of caves. Tow troglophilic vertebrates found in or |
near Illinois caves are the cave salamander (Eurycea lucifuga) and the spring cavefish (Forbesicthys agassizi). Diane Tecic, district heritage biologist for the Illinois Department of Natural Resources, looks for cave-adapted |
organisms in organic debris with Illinois caver Tim Sickbert. Most cave animals are trogloxenes and troglophiles; only 20 to 30% of the animals in North American caves are troglobites. Troglobites |
are animals that live exclusively in caves; they are especially interesting because of their unique morphological, physiological, behavioral, and life-history adaptations. Many troglobites, for example, lack body pigment. Because they |
live where there is no light, there is no evolutionary advantage for them in maintaining the colors that might be characteristic of their relatives and ancestors that live above ground. |
In cave-adapted species, the evolutionary pressure to maintain functional eyes is also greatly reduced, and these species have been under strong selective pressure to evolve other means of sensing their |
surroundings. Their legs and antennae usually have more sensory nerve endings than related above-ground species. These appendages serve important tactile functions and are often greatly elongated in cave-dwelling creatures. Adaptations |
that allow species to exist in an environment with very low nutrient input are not as obvious. Many cave-adapted species produce fewer offspring than their surface-inhabiting relatives, but individual eggs |
may contain more nutrients. In some species, timing of reproduction may be synchronized with spring flooding and its new supply of nutrients. Other species, lacking the above-ground seasonal cues of |
temperature and photoperiod, may reproduce year-round. Cave adaptations may include a reduced metabolic rate, allowing animals to live on limited food resources for long periods of time. Illinois has many |
troglobitic invertebrates but no troglobitic vertebrates. As cave-adapted species become specialized, they also tend to become geographically isolated. The geological and hydrological history of some areas may divide species into |
isolated populations, and these populations, over time, may evolve into distinct species. During glacial periods, caves, as serve as refugia for some aquatic, soil-, and litter-inhabiting animals. These species may |
become "stranded" in caves when glaciers retreat surface conditions are not suitable for recolonization. VULNERABITLIY OF CAVE ENVIRONMENTS Human disturbance affects cave ecosystems just as it affects other ecosystems. As |
a result of changes we make on the surface, we unknowingly alter cave environments, destroying unique and valuable organisms before we even know of their existence. The public knows very |
little about caves and the organisms that inhabit them. Small wonder then that the importance of protecting groundwater, caves, and cave life is not fully appreciated. It is not uncommon |
to find sinkholes filled with trash, serving as natural garbage cans for rural waste disposal. Visitors sometimes permanently damage caves with graffiti, break stalactites and stalagmites, and carelessly The very |
adaptations that allow troglobites to survive in the harsh cave environment make these animals more vulnerable to changes made by humans. The reduced metabolic rates that allow these animals to |
survive in a nutrient-poor environment also make them less competitive when organic enrichment is introduced in the form of fertilizers, livestock and agricultural waste, and human sewage. In Illinois, this |
effect is commonly seen in stream-inhibiting amphipods (small shrimplike animals) and isopods (small crustaceans related to terrestrial pillbugs or sowbugs). These groups contain troglobites that are highly adapted to cave |
environments; they also contain more opportunistic troglophilic species, which have a competitive advantage in the presence of high levels or organic waste. Amphipods and isopods feed on small particles of |
organic debris and on decomposers such as bacteria and fungi. Because they ingest large quantities of this material, they are exposed to contamination from a variety of pollutants. In Illinois, |
samples of these animals collected in 1992 were found to contain dieldrin and breakdown products of DDT. They were also found to contain moderate levels of mercury, although mercury was |
not detected in any water samples from the same sites. Sedimentation also threatens aquatic species. Topsoil run-off from rural development and agricultural fields enters caves readily when vegetative buffers around |
sinkholes are too small or nonexistent. This sediment fills the spaces in gravel streambeds, eliminating the microhabitats that allow many cavedwelling species to exist. As a result, cave streams with |
high sediment loads ten to contain few species. Sometimes, humans can't easily see the value of these subterranean systems, especially when their own interests conflict with the health of cave |
communities. Such a conflict is occurring now in our most biologically and hydrologically significant karst area, the Salem Plateau of Monroe and St. Clair counties. As part of the greater |
St. Louis metropolitan area, the Salem Plateau is experiencing rapid population growth. Scientists can estimate the level and types of threats that this growth brings to the biological integrity of |
the region, but it's much more difficult to develop protected areas, educational programs, and new regulatory mechanisms within the existing political, social, and geographic framework. Illinois caves are a high |
priority for conservation because cave organisms face serious threats from agriculture and increasing urbanization. Also, the unique and fragile cave and environment provides a home for organisms found nowhere else |
in the world. It is not usually possible to include the entire drainage basin of significant caves within nature preserves or other conservation easements. To manage a cave effectively, scientists |
must understand the hydrology of a cave's subterranean conduits. This knowledge is gained by doing extensive dye tracing studies and cave mapping. Both of these activities are time- and labor-intensive. |
Already, the drainage basins of some of our largest cave systems are being compromised by agriculture and rural housing projects. Educating the public-particularly politicians, farmers, and children-about land use and |
the impact of human activities is key to the long-term health of cave communities. We must also enact appropriate regulations for rural residential development-especially wastewater treatment-and for agricultural activities in |
a karst landscape. For more information on cave conservation and management, contact the National Speleological Society, 2813 Cave Avenue, Huntsville, AL 35810-4431, or Steven Taylor or Donald Webb at the |
Center for Biology, Illinois Natural History Survey, 607 East Peabody Drive, Champaign, IL 61820. Steven J. Taylor is an aquatic entomologist in the Center for Biodiversity at the Illinois Natural |
History Survey in Champaign. Donald W. Webb is an insect systematist, also at the Center for Biodiversity. A GOOD NEIGHBOR POLICY In a few caves in Monroe and St. Clair |
counties, you can find a small shrimplike creature that exists nowhere else in the world. The Illinois cave amphipod has made our corner of the world its home, but it |
may not be here long unless humans take steps to protect its environment. This unassuming cave creature has been proposed for listing as a federally endangered species. Cave amphipods inhabit |
the bottoms of pools and riffles in large cave streams, where they creep among cobbles and under stones, feeding on decaying leaf litter and organic debris. Food is scarce in |
this environment, and the amphipods have developed chemosensory structures that detect the odor of food sources, such as dead or injured animals. Injured or dying amphipods are vulnerable to such |
predators as flatworms, cave salamanders, and even other amphipods. But the greatest threat these vulnerable creatures face is the deterioration of the environment. The Illinois cave amphipod lives near the |
greater St. Louis metropolitan area, a region that has been experiencing dramatic population growth for the past 10 years. Continued urbanization without appropriate sewage treatment and disposal is especially threatening |
to the amphipods existence. Other serious threats are siltation and the presence of agricultural chemicals in subterranean Fortunately for the amphipod, the quality of life for people on the land |
above depends on water quality in streams below. Because agricultural chemicals and bacteria associated with sewage have been found in well water, springs, and cave streams in this area, a |
concerted effort is being made to improve the water quality in this karst region. Efforts to provide communities with safe drinking water could also provide a healthy cave environment and |
Prin. of Digital Logic & Comp. Org. A study of the computer as a physical device. Uponycompletion of the course, students will understandythe basic principles of digital logic and how ityis used to build useful hardware components,yunderstand the basic organization |
of a computerysystem in terms of digital hardware components andyhow instructions are executed using thoseycomponents, and have the knowledge and skillsynecessary to implement high-level languageyconstructs in assembly language. Prerequisite:yInformation Science and Technology 146 orypermission. |
not a dromaeosaur: the difference between the movies/pop culture blood thirsty beasts, and the real animal (or at least an aproximation). The second part is a step-by-step to draw your own Velociraptor in a dynamic pose. Again, I simplified enough so everyone can do it easily, omiting certain details that |
beaver as a tutorial. Instead of doing a drawing on a real life looking beaver, I thought it would be fun to show you how to draw a cartoon version of this wood chopping animal. There is an age old question that is asked by many kids and adults. And that question was once asked by me as well. What is this mind boggling |
brain tease? Well, did you ever wonder if beavers eat wood? I mean if you think about it, the beavers that I was used to seeing were on T.V. and these animated beavers cooked wood, ate wood, and even used wood to make these humongous dames that they are usually associated with. About two years ago I did a little resear... |
to find out if any of these myths were true, and here is what I found out. First off beavers are cousins to rats, mice, porcupines, and squirrels which means that they are a part of the rodent family. They live in ponds, rivers, lakes, streams and even marshes and they spend most of there time in the water due to the f... |
they have short legs and webbed feet. Because of their body build, they cannot move well on solid ground making them vulnerable to land predators. Do they really eat wood? The answer to that question is yes! Beavers love eating bark and leaves with their favorite tree being the aspen. They have also been known to eat b... |
answer your other question, yes they do build dams and lodges with the left over trees that they do not consume. Anyways no matter how you look at it, the beaver is a wonderfully pleasant animal that is fun to draw and color. You will learn "how to draw a beaver", step by step with easy to read instructions and simple ... |
step by step.” One thing I like to do is draw stuff that nobody else has just to stay original and creative. I know that you guys must know that by now anyway, but I just figured I would get that out on the table just to let you know why I choose to draw the things I do. Well lets get on with |
this learning experience shall we? First off aircraft carries are humongous warships that stay idol on the open sea. The sole purpose for these ships is to enable aircrafts to deploy using a swift command. The planes will also come back to the aircraft carrier to land and park until it's next mission. I guess you could... |
much like an airport. Now the reason why aircraft carriers stay so far out on the sea is because it makes striking and protecting enemy planes a whole lot easier because the reach is a lot more attainable opposed to being inland. The very first aircraft carrier was placed on March 20, 1922. The vessels name was the USS... |
the Navy's first flight carrier. By the time July rolled around of the same year, congress allowed all unfinished battleships to be transformed or converted, into aircraft carries. The two battleships that were converted was Lexington and Sarstoga. Did you know that the first landing area for a plane on sea was made of... |
named Eugene Ely flew his plane off a strip or platform made entirely out of wood. The wooden area was built aboard the USS Birmingham over the bow of the ship. Pretty cool huh? By the time the attack on Pearl Harbor came about, the U.S. Had several aircraft carriers out at sea. When the bombing happened, three vessels... |
fact that the carriers were not in the area at the time of attack. The ships that were left standing was the USS Saratoga, the USS Lexington, and the popular USS Enterprise. I did the best I could with this tutorial on "how to draw an aircraft carrier". I couldn't find any good pictures to reference from so I had to im... |
As of right now I am practicing on bettering my drawing skills for things like ships so later on down the road I can submit a lesson that will teach you “how to draw a battleship” in clarity. This lesson is going to be placed under the advanced category, but anybody can give it a go. I will be back later with another f... |
tutorial. Be sure to join me live tonight as I am drawing another dragon for a project I am doing. If you want to read more on aircraft carriers, just visit the US Navy and you will find all the information you need. Peace out people and happy drawing! |
the Surgeon General of the United States to issue a report on the health effects of soda and other sugary drinks. Citing the importance of the 1964 landmark Surgeon General’s report on tobacco use, the groups and individuals say a report on soda would appraise the health-damaging effects and alert health professionals,... |
of over-consuming sugary drinks. “Soda and other sugary drinks are the only food or beverage that has been directly linked to obesity, a major contributor to coronary heart disease, stroke, type 2 diabetes, and some cancers, and a cause of psychosocial problems,” the groups wrote in a letter to Secretary of Health and ... |
the average American drinks about 40 gallons of sugary drinks, all with little, if any, nutritional benefit.” The groups say that soda and sugary drinks have a devastating effect on the health of young people in particular. Each extra soft drink consumed per day was associated with a 60-percent increased risk of overwe... |
Type 2 diabetes, which used to occur primarily in middle-aged and older adults, is now becoming more common among teens. Though soda consumption has declined somewhat in recent years, consumption is still dangerously high, according to the letter. Even almost half of two- and three-year-olds consume sugary drinks every... |
from the Surgeon General, on topics as varied as tobacco, underage drinking, and obesity, have helped galvanize policymakers at all levels of government,” said Center for Science in the Public Interest executive director Michael F. Jacobson. “Unlike just about any other product in the food supply, sugar-based drinks ar... |
be one of the main pillars of the government’s prevention strategy.” The call for a Surgeon General’s report on soda and sugary drinks was organized by the CSPI, and included the American Diabetes Association, the American Heart Association, Consumer Federation of America, National Hispanic Medical Association, Prevent... |
Policy and Obesity. Public health departments in Boston, El Paso, New York City, and Philadelphia also signed the letter to Sebelius. # # # The Center for Science in the Public Interest is a nonprofit health advocacy group based in Washington, DC, that focuses on nutrition and food safety policies. CSPI is supported by... |
Eight new grants administered by NIDA aim to channel students' natural fascination with their behavior and their brains into appreciation and enthusiasm for neuroscience. Grantees are developing K-12 education programs that will engage young people in learning about the brain, inspire some to pursue careers in biomedic... |
the NIH Blueprint for Neuroscience Research Science Education, a cooperative effort among the 16 NIH Institutes, Centers, and Offices that support neuroscience research and the Science Education Partnership Award Program of the Division of Program Coordination, Planning, and Strategic Initiatives, Office of the Directo... |
programs in the neuroscience of learning and cognition for middle school science teachers, students, parents, and community groups. Teachers will have the opportunity to increase their knowledge by participating in a Summer Institute and online Professional Learning Community. An online project for students will be des... |
neuroscience careers. Dr. Eric Chudler heads a University of Washington project that will teach middle school students how chemicals in plants and herbs influence health and behavior. A supplementary educational resource kit will supply teachers with inquiry-based, hands-on science activities. Students may attend a sum... |
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