The Hippopotamus (Hippopotamus amphibius) is a large, plant-eating African mammal. With the pygmy hippo found in the swamps of west Africa, it completes the family Hippopotamidae.
Hippopotamuses ('hippopotami' is also accepted as a English plural form by the Oxford English Dictionary), commonly referred to as hippos, are gregarious, living in groups of up to 20 animals.
They spend most of the day up to their nostrils in the waters of tropical rivers, as their skin transpires much more moisture than most animals and they are extremely susceptible to sunburn. They can close their nostrils and remain completely submerged for more than ten minutes. They are buoyant and very skilled and graceful in water.
They feed on land mostly at night, consuming as much as 50kg (approximately 120 pounds) of vegetation per trip. They may range up to 30 kilometres from water in a round-trip.
Despite the popular image of the animal being easygoing and peaceful, the hippopotamus is actually one of the most dangerous African animals, said to account for more human deaths than any other mammal.
Conflict between hippo and man is most acute in the dry season when stressed animals have had to extend their night-time feeding period into daylight. They are more likely then to encounter people using the paths they force through reed-beds and other dense vegetation on their way to collecting water in the morning.
The hippo's canine teeth are 50cm (20 inches) long, and it uses its head as a battering ram. The animals stand 1.5 metres tall (5 feet) at the shoulder and weigh between 2,700 and 4,500 kg (6,000-9,900 lbs).
They are approximately the same size as the Black Rhinoceros; one or the other is the next-largest land animal after the three species of elephants.
The word hippopotamus comes, by way of Latin, from the ancient Greek ιππος ποταμος (hippos potamos), which means river horse.
A dwarf species, Phanourios minutis, existed on the island of Cyprus but became extinct at the end of the Pleistocene. Whether this was caused by human intervention is debated.
- Read the news article "Hippo Attack Kills Bathing Man"