Sperm whale

largest species of toothed whale

The sperm whale (Physeter catodon), also known as the cachalot, is the largest toothed whale. It has the biggest head of any animal. The head can be about 20 feet (6.1 m) long, and is about one-third of the whale's body. It also has biggest brain in the entire animal kingdom.[1] Its lower jaw is small and contains its huge, conical teeth. These teeth fit into sockets in the upper jaw.

Sperm whale
A mother and baby Sperm whale
Size comparison against an average human
Scientific classification
Binomial name
Physeter catodon
Linnaeus, 1758

Sperm whales are carnivores (meat-eaters). They mostly hunt medium-sized squid. They also eat many kinds of fish such as skate. Sometimes they hunt giant squid that live on the ocean bottom at great depths. They can dive up to 2250 m and stay underwater for two hours.

Sperm whales can reach up to 20.7m long, and weigh up to 80,000kg.[2][3] There is disagreement on the claims of adult males approaching, reaching or exceeding 24m in length.[4][5]



Like other toothed whales, the sperm whale uses echolocation, a way of sensing in which they emit high-pitched clicks and sense them as they bounce back off objects (like prey). This is crucial in hunting in the dark ocean depths.


  1. "Brains". American Museum of Natural History.
  2. Wood, Gerald (1983). The Guinness Book of Animal Facts and Feats. Guinness Superlatives. ISBN 978-0-85112-235-9.
  3. Carwardine, Mark (2008). Animal Records. New York: Sterling. ISBN 9781402756238.
  4. Ellis, Richard (2011). The Great Sperm Whale: A Natural History of the Ocean's Most Magnificent and Mysterious Creature. Zoology. Vol. 179. USA: University Press of Kansas. p. 432. ISBN 978-0-7006-1772-2. Zbl 0945.14001.
  5. McClain CR, Balk MA, Benfield MC, Branch TA, Chen C, Cosgrove J, Dove ADM, Gaskins LC, Helm RR, Hochberg FG, Lee FB, Marshall A, McMurray SE, Schanche C, Stone SN, Thaler AD. 2015. Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 3:e715 https://doi.org/10.7717/peerj.715