Rhinos are the second largest land mammals in the world, after elephants. Two main groups of Rhino exist in Africa and Asia consisting of five different species. The white, black, greater one-horned, Sumatran and Javan rhinos all have a number of common traits as well as a number of differences. The name rhinoceros comes from the Greek words "rhino," meaning nose, and "ceros," meaning horn.
Rhinos are large, muscular animals that range from 8 to 13 feet in length, 5 to 6 feet at the shoulder and 1,765 to 5,000 lbs., depending on species. The largest species is the white rhino and the smallest is the Sumatran. All rhinos have horns on their snouts formed from keratin, the same substance as hair and nails. Rhinos have thick, leathery skin that in some species can look almost like large armor plates. They are known for having poor vision but good hearing and when startled they may charge if they feel threatened.
Range and Habitats
The white and black rhinos are native to areas of eastern and southern Africa, both preferring open savanna and grassland. The black rhino is sometimes found in more forested habitats but generally near where the forest merges with grasslands. The other three rhino species are native to India or southeast Asia. The greater one-horned rhino lives in northern India, Pakistan and Nepal in open plains and swamp-like habitats. The Sumatran species is found in areas such Bhutan, Burma, Sumatra, Thailand and Malaysia. The Javan rhino is found in only two locations, both of which are national parks -- one in Thailand the other in Java. Both the Sumatran and Javan species are smaller rhinos that prefer tropical rain forest habitats.
Rhinos, as a rule, are herbivores and live on a wide range of plant materials depending on where they live. The African species feed mainly on grasses, twigs and tree bark often using their long horns to break higher branches in trees to find more food. The other three species spend more time deeper in rain forest environments and include fruits and some aquatic plants into their diets. Increased contact with agriculture also means these Asian species sometimes raid fields to eat crops.
With the exception of the white rhino, which does form small groups, rhinos are mostly solitary animals. Breeding can happen year-round, but is based mainly on times of food abundance. The size of the animals means that gestation periods tend to be long and usually only one offspring is born. Young rhinos stay with their mothers for up to two years before they are grown enough to look after themselves.