Glass Octopus

The glass octopus is a species of pelagic octopus found in tropical and subtropical waters around the world, notable for its nearly transparent body, through which its digestive tract, optic nerve and eyes are visible while only those organs remain opaque. It lives in the open ocean at considerable depth, and its transparency is thought to serve as camouflage against predators in the dimly lit midwater zone. Because of the difficulty of observing it in its deep-sea habitat, relatively little is known about its behavior and life history.