Wild Orangutan Great Ape Monkey Silhouette Postcard

Known for their intelligence, they live in trees and are the largest living arboreal animal. They have longer arms than other great apes, and their hair is typically reddish-brown, instead of the brown or black hair typical of other great apes. Native to Indonesia and Malaysia, they are currently found only in rainforests on the islands of Borneo and Sumatra, though fossils have been found in Java, the Thai-Malay Peninsula, Vietnam and China. There are only two surviving species in the genus Pongo and the subfamily Ponginae, which includes the extinct genera Gigantopithecus and Sivapithecus. Fruit makes up 65–90 percent of the orangutan diet. Fruits with sugary or fatty pulp are favored. Ficus fruits are commonly eaten, because they are easy to harvest and digest. Lowland Dipterocarp forests are preferred by orangutans because of their plentiful fruit; the same forests provide excellent timber for the logging industry and good soil conditions for palm oil plantations. Bornean orangutans consume at least 317 different food items that include: young leaves, shoots, seeds, bark, insects, honey, and bird eggs. Like the other great apes, orangutans are remarkably intelligent. Although tool use among chimpanzees was documented by Jane Goodall in the 1960s, it was not until the mid-1990s that one population of orangutans was found to use feeding tools regularly. A 2003 paper in the journal Science described the evidence for distinct orangutan cultures. According to research psychologist Robert Deaner and his colleagues, orangutans are the world's most intelligent animal other than humans, with higher learning and problem solving ability than chimpanzees, which were previously considered to have greater abilities. A study of orangutans by Carel van Schaik, a Dutch primatologist at University, found them capable of tasks well beyond chimpanzees’ abilities — such as using leaves to make rain hats and leakproof roofs over their sleeping nests. He also found that, in some food-rich areas, the creatures had developed a complex culture in which adults would teach youngsters how to make tools and find food.