The kitefin shark (Dalatias licha) is the world's largest glowing vertebrate and has no known natural predators. The kitefin shark in its habitat deep under the sea. It's not enough for an animal simply to glow; its light needs to resemble the ambient light it is trying to disappear against. Unlike other animals that use counterillumination, kitefin shark bioluminescence covers almost their whole body, including the dorsal fin. The kitefin shark could flip that idea on its head – using the very same trick to both hide from and find things to eat.