What Lives Underground?
Some scientists are interested in cave ecology and how cave animals interact with cave microclimates. Animals found in caves include everything from surface dwelling animals like raccoons that occasionally use the cave, to animals that have adapted exclusively to life in the cave (troglobites) . Troglobites cannot survive outside caves. These may include such diverse animals as eyeless fish and crayfish, cave beetles, flatworms, and other unusual types of insects. Many of these animals have lost body pigmentation and are white or transparent in color. Although the cave environment appears to be stable, change can and does occur. The temperature of the cave varies due to air movement near the entrances and the temperature of water entering the cave. In reality, some caves have their own weather systems which create wind due to temperature and pressure differences between the entrance and interior passageways.
Many animals, such as bats, cave crickets, and pack rats, regularly visit, raise their young, or hibernate in caves. These animals are called trogloxenes . Caves may support large numbers of different types of bats. Bats may be among the most beneficial animals to people and the ecosystem as insect-eaters and plant pollinators. The little brown bat can eat 600 mosquitoes in an hour thus performing the work of a "natural insecticide," helping control crop pests and other insects. The Mammoth Cave-Flint Ridge System in Kentucky, which is the most extensive cave system in the world, has a biodiversity of 43 mammals, 15 reptiles, 19 amphibians and 3 fish. In 1981, the United Nations designated Mammoth Cave National Park as a World Heritage Site. An excellent summary of the Mammoth Cave area and other caves found in the U. S. National Park System can be found on the World Wide Web at: http://www2.nature.nps.gov/grd/tour/caves.htm.