Hippopotamus, (Hippopotamus amphibius), also called hippo or water horse, amphibious African ungulate mammal.Often considered to be the second largest land animal (after the elephant), the hippopotamus is comparable in size and weight to the white rhinoceros (Ceratotherium simum) and the Indian rhinoceros (Rhinoceros unicornis).
The hippopotamus has a bulky body on stumpy legs, an enormous head, a short tail, and four toes on each foot. Each toe has a nail-like hoof. Males are usually 3.5 metres (11.5 feet) long, stand 1.5 metres (5 feet) tall, and weigh 3,200 kg (3.5 tons). In terms of physical size, males are the larger sex, weighing roughly 30 percent more than females. The skin is 5 cm (2 inches) thick on the flanks but thinner elsewhere and nearly hairless. Colour is grayish brown, with pinkish underparts. The mouth is half a metre wide and can gape 150° to show the teeth. The lower canines are sharp and may exceed 30 cm (12 inches).
