Rhinoceros
The Rhinoceros is a group of five species of odd-toed ungulates in the family rhinocerotidae. Two of these species are native to Africa (Black and White) and three to southern Asia (Indian, Javan and Sumatran).The rhinoceros family is characterized by its large size (one of the largest remaining megafauna), with all of the species able to reach one ton or more in weight although despite their size and dramatic appearance, are herbivores. They are protected by a very thick skin, 1.5–5 cm thick, formed from layers of collagen positioned in a lattice structure. They have relatively small brains for mammals this size (400–600 g) and a large horn (for which they are most persecuted!). 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.
The African species of rhinoceros lack teeth at the front of their mouths, relying instead on their powerful premolar and molar teeth to grind up plant food.Rhinoceros are killed by humans for their valuable horns, which are made of keratin, the same type of protein that makes up hair and fingernails. Both African species and the Sumatran Rhinoceros have two horns, while the Indian and Javan Rhinoceros have a single horn. Rhinoceros have acute hearing and sense of smell, but poor eyesight although can live to be about 60 years or more. The IUCN Red List identifies three of the species as critically endangered.