Scientific Name: Hippopotamus amphibius

Habitat: Rivers and lakes of equatorial Africa

Food: Grass, reeds, and water plants

Facts: Hippos are born in the water, and the calves can swim at birth. Although hippos can swim, they also spend much of their time actually walking on river or lake bottoms. An adult hippo can stay submerged for as long as five minutes. The red drops often seen oozing from the hippo's skin act to keep the skin moist.

The hippo's eyes, ears, and nostrils are placed high on its head. This enables it to see, hear, and smell easily while swimming. The ears and nostrils can be closed when the hippo goes under water.

The hippo is the only land mammal that can open its mouth a full 180 degrees. This unique ability gives the hippo the second-largest mouth of any creature on Earth. Only whales have bigger mouths.