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. They have a herbivorous diet, small brains 400–600 g (14–21 oz) for mammals of their size, one or two horns, and a thick 1.5–5 cm (0.59–1.97 in), 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.

Rhino d