The sperm whale or cachalot [a] Physeter macrocephalus is the largest of the toothed whales and the largest toothed predator. It is the only living member of the genus Physeter and one of three extant species in the sperm whale family , along with the pygmy sperm whale and dwarf sperm whale of the genus Kogia. The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. The females cooperate to protect and nurse their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature sperm whale has few natural predators, although calves and weakened adults are sometimes killed by pods of killer whales orcas.
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About fifty million years ago, the first whale-type mammal entered the seas. Archaeocetes were small in comparison to modern whales. The archaeocetes evolved from terrestrial animals believed to have been a dog-sized mammal with a tail. The question of whether archaeocetes gave rise to the two existing suborders, Mysticete and Odontoceti, is still a matter of controversy. Some scientists believe the two suborders may have risen from two different sources rather than one common ancestor. What we do know is warm-blooded whales, dolphins and porpoises evolved superbly to inhabit the aquatic world.
Formerly known as Physeter catodon , the Sperm whale is the largest of the toothed whales Odontoceti. Males reach 50 to 60 feet 15 to 18 m and weigh 48 tons 43 m tones , while females grow to feet 4. This species is very distinctive looking, with a massive bluntly square head which can be one third the length of its body. This whale has a long, narrow lower jaw which contains teeth, while the top jaw contains sockets into which the lower teeth fit. Toothed whales have a single nostril, unlike baleen whales which have two.
Sperm whales are the largest of the toothed whales and have one of the widest global distributions of any marine mammal species. They are found in all deep oceans, from the equator to the edge of the pack ice in the Arctic and Antarctic. They are named after the waxy substance—spermaceti—found in their heads. The spermaceti is an oil sac that helps the whales focus sound.