IMAGE RHINOCEROS SKIN

The species diverged during the early Pliocene (about 5 million years ago). The two African species, the white rhinoceros and the black rhinoceros, belong to the tribe Dicerotini, which originated in the middle Miocene, about 14.2 million years ago. The living species fall into three categories. The family Rhinocerotidae consists of only four extant genera: Ceratotherium (white rhinoceros), Diceros (black rhinoceros), Dicerorhinus (Sumatran rhinoceros), and Rhinoceros (Indian and Javan rhinoceros). The name has been in use since the 14th century. The collective noun for a group of rhinoceroses is crash or herd. The plural in English is rhinoceros or rhinoceroses. The word rhinoceros is derived through Latin from the Ancient Greek: ῥῑνόκερως, which is composed of ῥῑνο- ( rhino-, ' nose') and κέρας ( keras, ' horn') with a horn on the nose. See also: List of perissodactyls RhinocerotidaeĬladogram following a phylogenetic study. A market also exists for rhino horn dagger handles in Yemen, which was the major source of demand for rhino horn in the 1970s and 1980s.

Rhino horns are made of keratin, the same material as hair and fingernails, and there is no good evidence of any health benefits. The contemporary market for rhino horn is overwhelmingly driven by China and Vietnam, where it is bought by wealthy consumers to use in traditional Chinese medicine, among other uses. Rhinoceros are killed by poachers for their horns, which are bought and sold on the black market for high prices, leading to most living rhinoceros species being considered endangered. Unlike other perissodactyls, the two African species of rhinoceros lack teeth at the front of their mouths they rely 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 when necessary.

IMAGE RHINOCEROS SKIN

They have a herbivorous diet, small brains (400–600 g) for mammals of their size, one or two horns, and a thick (1.5–5 cm), protective skin formed from layers of collagen positioned in a lattice structure. Rhinoceroses are some of the largest remaining megafauna: all weigh at least one tonne in adulthood. (It can also refer to a member of any of the extinct species of the superfamily Rhinocerotoidea.) Two of the extant species are native to Africa, and three to South and Southeast Asia. A rhinoceros ( / r aɪ ˈ n ɒ s ər ə s/ from Ancient Greek ῥῑνόκερως ( rhīnókerōs) 'nose-horned' from ῥῑνός ( rhīnós) 'nose', and κέρας ( kéras) 'horn'), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates in the family Rhinocerotidae.

Image rhinoceros