Fish that live in underground caves are very unusual. Scientists say that they are the survivors of fish that were trapped in caves billions of years ago. They were originally like other fish, but their dark environment caused their bodies to go through a lot of changes. The characteristics of the cave fish slowly became very different from those of other fish. Today the cave fish have became almost completely eyeless. This change developed because they did not need eyes any more their world was black. There was nothing to see . these fish lost their need for a protective coolorig for the same reason. Now cave fish have no color at all. In face,some of them are so colorless you can see through their skin. Cave fish also do not have any hearing. They lost this ability with the others. they did not use theirears underground because there was nothing to hear. Fish that live in underground caves do have an extraordinary sense of touch. Over the ages they have learned to move around by touch as well aswe move around by sight.