Dolphin Killer whales have the second largest brain mass of any animal on earth, next to the sperm whale. The brain to body mass ratio in some is second only to humans. Self-awareness is seen, by some, to be a sign of highly developed, abstract thinking. Self-awareness, though not well-defined scientifically, is believed to be the precursor to more advanced processes like meta-cognitive reasoning (thinking about thinking) that are typical of humans. Research in this field has suggested that cetaceans, among others, possess self-awareness. The most widely used test for self-awareness in animals is the mirror test in which a mirror
Cuvier's beaked whale another that had stranded itself at Aresquiès, Hérault, in May of the same year, and found the two to be identical. There is no connection between Cuvier's beaked whale and the mythical Ziphius, or "Water-Owl", a creature in medieval folklore which had the characteristics of both an owl and a fish. Its dorsal fin was said to be sword-shaped, and pierced ship's hulls, while the beak was said to resemble an owl's head. The body of Cuvier's beaked whale is robust and cigar-shaped, similar to those of other beaked whales, and can be difficult to distinguish from many of the