hippopotamus

hippopotamus, herbivorous, river-living mammal of tropical Africa. The large hippopotamus, Hippopotamus amphibius, has a short-legged, broad body with a tough gray or brown hide. The male stands about 5 ft (160 cm) high at the shoulder and weighs about 5 tons (4,500 kg); the female is slightly smaller. The mouth is wide, and the incisors and lower canines are large ivory tusks that grow throughout life. The eyes are near the top of the head, so the animal can see when nearly submerged. Hippopotamuses usually live in herds of about 15 animals. Much of their time is spent standing or swimming underwater, where they feed on aquatic plants; they must rise to breathe every 5 minutes or so. At night groups of animals feed on the shore. The hippopotamus is hunted for meat, and Africans have used the hide for shields and whips. Once widespread in Africa, the animal is now rare except in unsettled areas and reserves. The pygmy hippopotamus, Choeropsis liberiensis, is found in W Africa. It is about 30 in. (75 cm) tall at the shoulder and weighs about 400 lb (180 kg). It tends to be solitary and spends much of its time on the shore, sleeping by day in thickets. Recent DNA (genetic material) studies indicate that whales are most closely related to hippopotamuses. Hippopotamuses are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Artiodactyla, family Hippopotamidae.

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hippopotamus

Huge amphibious African mammal (Hippopotamus amphibius). Once found throughout sub-Saharan Africa, it is now restricted to parts of eastern and southeastern Africa. It has a barrel-shaped body, an enormous mouth, short legs, and four toes on each foot. It commonly reaches a length of 11.5 ft (3.5 m), a height of 5 ft (1.5 m) at the shoulder, and a weight of 7,000 lb (3,200 kg). The skin is very thick, nearly hairless, and grayish brown above, lighter and pinkish below. The ears and nostrils protrude above water when the rest of the body is submerged. Hippopotamuses live near rivers, lakes, swamps, or other permanent bodies of water, usually in groups of 7 to 15. During the day they sleep and rest in or near the water. At night they go on land to feed on grasses, which they crop with their hard-edged lips. In water they can swim fast, walk along the bottom, and remain submerged (with ears and nostrils closed) for five minutes or more. The rare pygmy hippopotamus (Hexaprotodon liberiensis) is the only other species of the family Hippopotamidae. Living along streams and in wet forests and swamps of West Africa, it is about the size of a domestic pig.