Which toothed whale is the largest member of its group?

The sperm whale is the largest toothed whale.

Adult male sperm whales can grow to roughly 16 metres and weigh around 40 tonnes, making them substantially larger than other living toothed whales. Females are smaller, a marked difference that is called sexual dimorphism.

Sperm whales are famous for deep diving. They hunt squid and fish in the dark deep ocean, using echolocation to locate prey. Their enormous heads contain spermaceti, a waxy substance once highly prized by the whaling industry, although its exact biological functions remain debated.

The species suffered severe population declines during commercial whaling, especially in the nineteenth and twentieth centuries. Sperm whales are now protected in many jurisdictions, but they still face threats from ship strikes, entanglement, underwater noise, and pollution.