A killer whale's eyes appear similar to the eyes of other cetaceans, although the prominent, oval white patch behind each eye can be distracting and misleading upon inspection. The famous coloration of the killer whale, a type of countershading, is believed to assist in disrupting the outline of the animal.
Killer whales are the largest members of the family Delphinidae, which includes dolphins, porpoises and false killer whales. The killer whale is an apex predator and has no natural enemies. Diet varies across specific populations but generally consists of fish and squid. Some killer whales prefer mammals such as pinnipeds and other whales. As highly social animals, killer whales are believed to be some of the most intelligent animals on the planet.