The hippo's nose, ears, and eyes are on the top of its head, and they protrude from the water while the rest of its head and its body lie beneath the surface. That way a hippo can breathe, see, and hear even while its body is submerged. When a hippo sinks completely underwater, its nose and ears automatically close so that no water seeps in. Hippos are excellent swimmers and can hold their breath for about five minutes. They can even walk along the bottoms of rivers and lakes.

At dusk, hippos leave their watery daytime spot, lumber onto land, and walk as far as 5 miles (8 kilometers) from the water to graze on short grasses, their main food. They are not considered to be very fast moving animals, but in short bursts they can run up to 30 miles (48 kilometers) per hour!

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Grazing until dawn, a hippo may eat up to 150 pounds (68 kilograms) of grass a night. They avoid the heat of the sun by returning to a river or lake before sunrise.