A cave is "a natural opening in the ground extending beyond the zone of light and large enough to permit the entry of man," according to the U.S. Geological Survey. Caves can range in size from single rooms to large formations with winding passageways that extend for miles. Caves typically form in types of rock, such as limestone, that dissolve in water. It can take tens of thousands to hundreds of thousands of years for caves to form. The study of caves is called speleology, and the exploration of caves is called spelunking. Caves are famous of their dripstone features called speleothems, the most well-known of which are stalactites and stalagmites. Many of the strange creatures found in caves have adapted to live in near or total darkness — some are blind to visible light. See cave pictures and read about the latest cave discoveries and speleological research below.
Imagine a social- networking site that not only predates not only the internet but even a European presence in the Americas. That's how researchers from the University of Leicester describedare theirdescribing the discoveries they've made after three year
Pity the male woolly mammoth: These poor creatures were more likely to meet their end in natural traps — falling through thin ice, tumbling into holes or getting stuck in mudflows — than their female counterparts, a new study finds.
The Cooperative Adventure for Valuing and Exercising human behavior and performance Skills (CAVES) is a two-week astronaut training course that occurs yearly in the Sa Grutta caves in Sardinia, Italy.