Hippopotamus - large, mostly herbivorous, semiaquatic mammal,

 

The Hippopotamus is an herbivorous mammal with a life span of up to 40 years. The hippos spend most of their day in water which helps them staying cool in a hot, tropical climate which is the natural habitat of hippopotamus. They are round, large, and water-loving animals which are native to Africa. They have 5 cm /(1.9685 inches) thick skin on edges while it is thinner elsewhere and almost hairless. They have a greyish brown color and have a mouth half a meter width with sharp lower canines. The ears, eyes and nose of hippos are on the upper part of head, and they project from the water. 

However, its body and rest of the head are submerged in the water. They are amazing swimmers and can hold their breath for about five minutes. Hippos leave the water at dusk and walk on land for about 5 miles from water for grazing on short grasses which is their main food. They return to the lake or river before sunrise to avoid heat of the Sun. Pigs, Whales and Dolphins are the closest relatives to hippopotamus. Human beings use meat, hide and ivory of hippopotamus. 

They are considered social as they hang out in groups of about 10 to 30 members called schools. These schools are led by a dominant male most of the times. Hippos are very loud and aggressive animals. They are very dangerous as they have large teeth to fight off threats including humans. But their aquatic characteristics and huge size keeps them safe from most predators.