The hippopotamus is responsible for more human fatalities in Africa than any other large animal. Male hippos actively defend their territories which run along the banks of rivers and lakes. Females have also been known to get extremely aggressive if they sense anyone coming in between their babies, who stay in the water while she feeds on the shore. Hippos can run at speeds of over 20 miles an hour and they have enormous jaws which host up to 20-inch canines.

The common hippopotamus (Hippopotamus amphibius), or hippo, is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus (Choeropsis liberiensis or Hexaprotodon liberiensis). The name comes from the ancient Greek for "river horse". After the elephant and rhinoceros, the common hippopotamus is the third-largest type of land mammal.

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