A sperm whale is the largest of the toothed whales and the largest toothed predator. It is a pelagic mammal with a worldwide range and is found in all deep oceans. The species is named after the waxy substance called spermaceti found in their heads, which was originally mistaken for the whales semen. Sperm whales are mostly dark gray, though some whales have white patches on the belly. They have a hump rather than a dorsal fin and have triangular-shaped flukes or tails. Their heads are extremely large, accounting for about one-third of their total body length. The skin just behind the head is often wrinkled, which increases surface area, leading to greater heat loss.

Sperm whales are a matriarchal species, and females and young males live together in groups called pods, while mature males (bulls) live solitary lives outside of the mating season. Females give birth every four to twenty years and care for the calves for more than a decade. The species is protected by the International Whaling Commission moratorium and is listed as vulnerable by the International Union for Conservation of Nature.

Sperm whales are constantly feeding and can eat about three percent of their body weight daily, sometimes up to two tons of food. They can dive to depths of more than 3,000 feet in search of prey such as squids. Sperm whales are known to produce a series of clicks called codas, and each whale has a distinctive coda. Scientists think that sperm whales recognize each other by these clicks.

In summary, a sperm whale is a large toothed whale with a worldwide range that is named after the waxy substance called spermaceti found in their heads. They are mostly dark gray, have a hump rather than a dorsal fin, and have triangular-shaped flukes or tails. Females and young males live together in groups called pods, while mature males live solitary lives outside of the mating season. They are constantly feeding and can dive to depths of more than 3,000 feet in search of prey such as squids.