why do deep sea fish have large eyes
Deep sea fish The fish of the deep-sea are among the strangest and most elusive creatures on Earth. In this deep dark unknown lie many unusual creatures that have yet to be studied. Since many of these fish live in regions where there is no natural illumination, they cannot rely solely on their eyesight for locating prey and mates and avoiding predators; deep-sea fish have evolved appropriately to the extreme sub-photic region in which they live. Many of these organisms are blind and rely on their other senses, such as sensitivities to changes in local pressure and smell, to catch their food and avoid being caught. Those that aren't blind have large and sensitive eyes that can use bioluminescent light. These eyes can be as much as 100 times more sensitive to light than human eyes. Also, to avoid predation, many species are dark to blend in with their environment.[10]