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There are about 65 kinds of toothed whales. They differ greatly in size, in shape, and in the number of teeth they have. Some toothed whales eat fish, and others eat such animals as cuttlefish and squid.
Scientists divide the various kinds of toothed whales into five groups: sperm whales, beaked whales, belugas and narwhals, dolphins and porpoises, and river dolphins.
Sperm Whales grow up to 60 feet long and range in color from blue-gray to black. Sperm whales have an enormous, square-shaped head. It makes up about a third of the total body length. The lower jaw is long and extremely thin. It has 16 to 30 peglike teeth on each side. Almost all sperm whales live only in tropical and temperate waters, though a few males spend the summer in polar seas. Sperm whales dive to great depths in search of their food, which consists mainly of cuttlefish and squid.
Beaked Whales have a beaklike snout and only two or four teeth in the lower jaw. Some kinds of beaked whales grow only about 15 feet long, and others reach 40 feet. Beaked whales live in all the oceans and feed mainly on squid and fish.
Belugas and Narwhals measure 10 to 15 feet long. Narwhals and most belugas live in the Arctic, but some belugas are found farther south. Belugas and narwhals eat mostly fish and squid. Narwhals only have two teeth. Among most males, the left tooth develops into a spiral tusk up to 9 feet long.
Dolphins and Porpoises live in all the oceans. Most porpoises grow 4 to 6 feet long, making them the smallest cetaceans. Dolphins range from about 7 to 30 feet long. The largest dolphins include killer whales and pilot whales.
River Dolphins are the only freshwater whales. They live in the muddy waters of such rivers as the Amazon in South America and the Ganges in India. They measure about 8 feet and have a long beak and poorly developed eyesight.
Library >> Science >> Zoology >> Mammals >> Order Cetacea
This page was last updated on September 22, 2017.