Adaptations

With the deep sea being such an extraordinary, unusual and often dangerous environment, it's inhabitants must adapt to survive in the unforgiving depths. Most species which dwell in the deep sea have some sort of adaptation or function which enables them to survive in their environment. Many are "Bioluminescent" - meaning their bodies can produce light naturally. There are some distinct physical features that are common between most creatures of the deep; such as big eyes, large mouths and teeth, dark coloration, and stretchy stomachs of proportions which greatly exceed that of their body size. Many deep sea fish also have a dark lining in their stomach which conceals the bioluminescent glow of other fish they have eaten, and thereby prevents said glow from revealing them to other, more threatening fish...


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Others, such as the deep sea Angler Fish (shown above) have developed what could be considered natural fishing lines - Retractable cords protruding from the fish's head or spine, upon which hang a bioluminescent orb used to lure in smaller prey close to the mouth; where they would then be devoured quickly, painfully and without mercy.