Toothed whale brain size with the expected brain size based on such allometric analysis provides an encephalisation quotient that can be used as another indication of animal intelligence. Sperm whales have the largest brain mass of any animal on earth, averaging and in mature males, in comparison to the average human brain which averages in mature males. The brain to body mass ratio in some odontocetes, such as belugas and narwhals, is second only to humans. Dolphins are known to engage in complex play behaviour, which includes such things as producing stable underwater toroidal air-core vortex rings or "bubble rings". Two main
Whale shark two small eyes at the front. Whale sharks are grey with a white belly. Their skin is marked with pale yellow spots and stripes which are unique to each individual. The whale shark has three prominent ridges along its sides. Its skin can be up to thick. The shark has a pair of dorsal fins and pectoral fins. Juveniles' tails have a larger upper fin than the lower fin, while the adult tail becomes semilunate. The whale shark's spiracles are just behind its eyes. The whale shark is the largest non-cetacean animal in the world. The average size of adult