Kings of the underworld
Trapped deep underneath the surface and left to evolve in isolation for thousands of years, cave animals are some of nature's most bizarre and fascinating creatures. Scientists call them "troglobites," and some species are so rare that they consist of a handful of individuals in a single cave.
This is evolution at its most extreme, but troglobites are more common than you might think. Any time a new cavern is discovered, penetrated and explored, there's the potential of finding a new species. Here's our list of 10 incredible cave animals that have evolved to live in the darkness. (Text: Bryan Nelson)