A rhinoceros, 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. Two of these extant species are native to Africa and three to Southern Asia. They generally eat leafy material. The two African species of rhinoceros lack teeth at the front of their mouths, relying instead on their lips to pluck food. Rhinoceros are killed by humans for their horns, which are bought and sold on the black market. The IUCN Red List identifies three of the species as critically endangered.
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