These whales are aggressive. Males have been known to ram and sink whaling ships. Sperm whales grow to about 60 feet (18 m) in length and are dark bluish-gray above, light gray below. The sperm whale has a large, rectangular head with teeth only in the lower jaw. It is the only polygamous species of whale.

Sperm whales yield an oil of fine quality, which has been used to lubricate watches, clocks, and scientific instruments; a wax (spermaceti), which has been used in candle-making, soaps, and cosmetics; and ambergris, which has been used in making perfume.

As you might expect, a toothed whale has teeth. Oddly enough, some toothed whales have only one tooth, while others have more than 200. All whales belong to an order of mammals called cetaceans (suh TAY shuhnz). Cetaceans are divided into two suborders: toothed whales and baleen (BAY leen) whales. Baleen whales have no teeth at all.

The killer whale is a toothed whale. It belongs to the family of whales called ocean dolphins. Bottle-nosed dolphins and pilot whales also belong to this family. There are several other families of toothed whales. These include porpoises, river dolphins, beaked whales, sperm whales, and belugas (buh LOO guhz) and narwhals.

Most common of these widely distributed whales is the North Atlantic bottle-nosed whale. It has a bulging forehead and grows to about 30 feet (9 m) in length.

Most beaked whales have long, slender bodies. Many have only two teeth in their lower jaws. Most have no upper teeth at all.

A Baird’s beaked whale can be up to 42 feet (13 meters) long. It’s probably the largest of the beaked whales. It has a long beak—which looks a lot like the beak of a bottled-nosed dolphin. Males of this species have two pairs of teeth in their lower jaws. Scientists think that beaked whales use their teeth for fighting rather than for feeding. They may feed by sucking up their prey, which consists mostly of squid.

Most beaked whales live offshore, in deep waters. Of all whales, beaked whales are among the deepest divers. And their dives can last more than an hour. But they are not very fast swimmers.

The largest of these is the killer whale, a dolphin.

Toothed whales found in the Arctic.

Like fish, whales spend their entire lives in water. Their bodies are sleek and shaped like torpedoes. They’re perfectly suited for life in a watery world, where swimming is the best way to get around.

Toothed whales live in all the oceans of the world. Some, however, prefer deep water to shallow water. Sperm whales like deep water—as do beaked whales.

Dall’s porpoises also like the open seas. But most other porpoises seem to prefer shallow coastal waters. They are often seen in harbors and other inlets. Belugas and narwhals also hug the coast. But they like the pack ice around the North Pole.

River dolphins live in some of the world’s large river systems. Ocean dolphins prefer the open seas. But, only the killer whale has a truly worldwide habitat. It is found in all the oceans and seas of the world.

A killer whale is big—but a sperm whale is even bigger. It can weigh as much as 55 tons (50 metric tons). An adult male sperm whale grows to about 60 feet (18 meters) long. That’s twice the length of a killer whale! In size, the sperm whale is indeed the king of toothed whales.

Sperm whales also make the deepest and the longest dives of all toothed whales. Sperm whales dive to find their favorite prey—deep-water squids. Scientists think the whales may have some terrible battles with giant squids. Scientists think this because of the scars they have seen on the bodies of the whales.

Sperm whales spend most of their lives in a nursery school or a bachelor school. A nursery school is made up of adult females and their young. A bachelor school is made up of young males only. When a male sperm whale becomes an adult, he leaves the bachelor school and lives on his own.