orangutan, (genus Pongo), any of three of Asian great found in s on the Southeast Asian islands of and . The (Pongo pygmaeus) inhabits large portions of Borneo, whereas the Sumatran orangutan (P. abelii) and the Tapanuli orangutan (P. tapanuliensis) are limited to northern Sumatra. Orangutans possess cognitive abilities comparable to those of the and the , which are the only more closely related to humans. Natural history male orangutanMale orangutan (Pongo pygmaeus) with cheek pads.(more)Orangutans are not as powerfully built as the but are larger than the . The adult male is typically twice the size of the female and may attain a height of 1.3 metres (4.3 feet) and a weight of 130 kg (285 pounds) in the wild; females weigh 37 kg (82 pounds) or less. Older males develop wide cheek pads, a unique feature among . The typically dark tan or brownish is covered with relatively coarse and usually sparse red . Adult males and some older adult females may have partially or entirely bare backs, but the hair on a male can be so long as to look like a cape when he moves his arms. Diet and locomotion orangutan swinging along branchesOrangutan (Pongo pygmaeus) swinging along tree branches.(more)Orangutans are the largest arboreal , spending more than 90 percent of their waking hours in the . During the day most of their time is divided equally between resting and feeding. Orangutans are predominantly ripe-fruit eaters, although they consume more than 400 different types of , including and, on rare and opportunistic occasions, . Almost every night orangutans construct a sleeping platform in the trees by bending and breaking branches, leaves, and twigs. Unlike the African , orangutans frequently use vegetation to protect themselves from the . orangutanOrangutan (Pongo pygmaeus).(more)In addition to feeding and resting, orangutans also spend short periods of time traveling through the forest canopy, where they typically scramble by using all four hands and feet. Orangutans occasionally swing through the trees using only their arms (). Although their are short, their arms are proportionately the longest of those of the great apes. The hooklike hands have long and palms with short . The feet resemble the hands in having opposable big toes that are similar to the thumbs. Another arboreal adaptation is flexible hip joints that allow orangutans similar movement in their legs and arms. On the ground orangutans are slow; a person can easily keep pace with them. They are not walkers like the African apes but instead walk on closed fists or extended palms. Reproduction There are two phases of sexual maturation among males—adult and subadult. Adult males are larger and exhibit striking secondary sexual characteristics, particularly the flat and prominent that develop along the sides of the . The pads enhance the size of the head and are linked with increased levels of . Adult males also have a throat pouch that serves as a resonating chamber for the “long call,” a sequence of roars that can sometimes be heard for 2 km (1.2 miles). Males typically for a minute or more; up to five minutes in length have been recorded, giving the call its name. Females virtually never give the full sequence of the long call, as it serves to space males and attract sexually receptive females. Otherwise, orangutans are generally silent. Subadult males lack the wide cheek pads and large throat pouch, and they generally do not long call. Although smaller than adult males, subadults are still as large as or larger than adult females. Subadults may remain in this state for 10 to 20 years. This arrested development has been linked with stress associated with the presence of adult males., Orangutans are great apes native to the rainforests of Indonesia and Malaysia. They are now found only in parts of Borneo and Sumatra, but during the Pleistocene they ranged throughout Southeast Asia and South China. Classified in the genus Pongo, orangutans were originally considered to be one species., Orangutan, any of three species of Asian great apes found in rainforests on the Southeast Asian islands of Sumatra and Borneo. They are renowned for their cognitive abilities, which are comparable to those of the gorilla and the chimpanzee..