Native to Indonesia and Malaysia, orangutans (Pongo pygmaeus and Pongo abelii) are found only on the islands of Borneo and Sumatra. Their name derives from the Malay and Indonesian phrase ‘orang hutan’, meaning ‘person of the forest’. Orangutans spend most of their time in trees, and live a more solitary lifestyle than the African great apes. Social bonds occur primarily between mothers and their offspring, who stay together until adolescence. Fruit makes up about 60% of an orangutan’s diet; other food items include young leaves, shoots, seeds, bark, insects, and bird eggs. Orangutans use a variety of sophisticated tools and construct elaborate sleeping nests each night from branches and foliage.

Two species of orangutan are recognized: the Bornean orangutan and the Sumatran orangutan.