The malay word orangutan means “person of the forest” these long- haired orangish primates found only in Sumatra and Borneo, are highly intelligent and are close relatives of humans.

Orangutans have an enormous arm span. A male may stretch his arms some 7 feet (2 meters) from fingertip to fingertip – a reach considerably longer than his standing height of about 5 feet (1.5 meters). When orangutan do stand, their hands nearly touch the ground.

Orangutans’ arm are well suited to their lifestyle because their spend much of their time ( some 90 percent) in the trees of their tropical rain forest home. they even sleep alot in nests of leafy branches. They use large leaves as umbrellas and shelters to protect themselves from common rains.

These celeral primates forage for food during daylight hours. Most of their diet consists of fruit and leaves gathered from rain forest trees. They also eat bark, insect and, on rare occasion, meat.

Orangutans build new nest everyday as they are arboreal. They are more solitary than other apes. Adult males are loners but anytime will stay together with female just for copulate. As they move through the rainforest they make plenty of rumbling,howling calls to ensure that their stay out of each others way. The adult male “long call” can be heard 1.2 (2 kilometers) away.

Mothers and their young, how ever share a strong bond. Infants will stay with their mothers for some six or seven years untill they develope the skill to survive on their own. Wild females orangutangive birth only every seven or eight years – the longest time periode of any animal. The animals are long-lived and have survived as long 50 to 60 years in captivity.

Because orangutan live only in two island in the worls (Borneo and Sumatra) and because they are so dependent upon trees, they are particularly susceptible to logging in these areas. Unfortunately, deforestation and other human activities, such as hunting and plantation have placed the orangutan in danger of extinction.

Source : http://animals.nationalgeographic.com/animals/mammals/orangutan/