People grind up the horns and then consume them believing the dust has therapeutic properties. By weight, rhino horns cost as much as gold on the black market. East Asia, specifically Vietnam, is the largest market for rhino horns. Rhinoceros are killed by humans for their horns, which are bought and sold on the black market, and which are used by some cultures for ornamental or traditional medicinal purposes. Unlike other perissodactyls, the two African species of rhinoceros lack teeth at the front of their mouths, relying instead on their lips to pluck food. They generally eat leafy material, although their ability to ferment food in their hindgut allows them to subsist on more fibrous plant matter, if necessary.

Members of the rhinoceros family are characterized by their large size (they are some of the largest remaining megafauna, with all of the species able to reach one tonne or more in weight) as well as by an herbivorous diet a thick protective skin, 1.5–5 cm thick, formed from layers of collagen positioned in a lattice structure relatively small brains for mammals this size (400–600 g) and a large horn. Two of these extant species are native to Africa and three to Southern Asia. A rhinoceros ( / r aɪ ˈ n ɒ s ər ə s/, meaning ' nose horn'), often abbreviated to rhino, is one of any five extant species of odd-toed ungulates in the family Rhinocerotidae, as well as any of the numerous extinct species.

Western black rhinoceros anatomy