Sperm whale

The sperm whale is the largest of the toothed whales, and the largest toothed predator on Earth. It lives in deep waters in every ocean, from the tropics toward the poles. A mature male is about 16 metres long on average, and its huge, square head can make up as much as a third of its body.

This whale is a record-breaker in several ways. It can dive down to about 2,250 metres, making it one of the deepest-diving mammals. It makes clicks that reach 236 decibels underwater, the loudest sound known from any animal, and it has the biggest brain on Earth, more than five times heavier than a human brain. It is listed as vulnerable, and today commercial whaling is banned.

Where it lives and how it hunts

Sperm whales roam the open ocean worldwide and move with the seasons to feed and breed. Females and young males travel together in groups, while grown males mostly live alone except when mating. They dive deep to hunt squid, including giant squid, and also eat some fish. They find prey in the dark with echolocation, which means sending out clicks and listening for the echoes.

Spermaceti and whaling

The head holds a waxy liquid called spermaceti. Early whalers mistook it for the whale's seed, which is how the animal got its name. People once burned it in lamps and used it in candles and lubricants, so sperm whales were hunted heavily in the 1800s, a story told in the novel Moby-Dick. A whale's gut can also make ambergris, a waxy lump that is still used in perfume. Hunting is now limited by an international moratorium.

On the globe

On the toy globe the sperm whale swims in the North Atlantic southwest of the Azores. Look for the big blocky head, which is the animal's most famous feature.