The hippopotamus is the third heaviest animal in the world (the first being the elephant and the second the rhinoceros). Hippos live in western, central, eastern, and southern Africa.
The hippopotamus may look like a friendly giant with a built-in smile, but it is actually very dangerous and can kill animals with a single bite. The hippo has fierce-looking teeth which are used for eating grasses, roots, large reeds, and aquatic plants. The lower canines can grow to be 20 inches (51 cm) long, 13 inches (33 cm) longer than the tooth of Tyrannosaurus rex. Hippos eat as much as 90 pounds (41 kg) of food a day. At night, they come out of the water to feed on the land. During the day, they spend up to 18 hours in a lake or river, shielding themselves from the hot African sun.
The skin of the hippo is five inches (13 cm) thick. The skin secretes a pinkish fluid that oozes over the hippo’s body and protects it from the scorching sun. The hippo is hairless except for the tips of the ears and the muzzle.
Very graceful in the water, hippos tuck their front legs in and paddle with their hind feet. Their eyes, nose, and ears are on the top of the head, allowing them to stay nearly submerged and still know what is going on. When the hippo dives, it presses its short ears against its head and closes its nostrils. It can stay underwater for over five minutes. Hippos also like to wallow in mud like pigs. Hippos share the water with crocodiles. Most crocodiles leave baby hippos alone because a protective mother can, and will, bite crocodiles in two if provoked.
The hippopotamus is very social, living in groups ranging from 15 to 20. One dominant male will reign over the group for as long as ten years. Other males stay in bachelor groups until bold enough to challenge the leader.
After a gestation period of eight months, the hippopotamus has a single calf, born during the rainy season. Sometimes the baby is born underwater and must surface quickly to take its first breath. It usually nurses underwater for about five months. A baby will stay with its mother for several years, and often several youngsters are seen following a single female. Female hippos will take turns watching the young while the others feed.
Hippos can be very dangerous. They have fatally injured people while attacking boats. Hippos often overgraze an area, which can cause severe soil erosion. This results in the removal of the hippos by organized hunting.
Artiodactyla • Hippopotamidae • Hippopotamus amphibius
Height: 5 feet (1.5 m)
Weight: 5,525 pounds (2,500 kg)
Length: 14–15 feet (4–5 m)
Life Span: 45 years
Special Design Feature: The hippopotamus’s eyes, nose, and ears are on top of its head. They can close their nose and ears and comfortably dive in the water.
Did You Know? The skin of the hippo is five inches (13 cm) thick and the skin secretes a pinkish fluid to protect it from the sun.