Introduction to Orangutan
Orangutan, a species of anthropoid (manlike) ape. Orangutans are related to gorillas, chimpanzees, and gibbons. They are found in tropical rain forests of the islands of Sumatra and Borneo. (Their name comes from the Malayan for "man of the woods.")
An adult male is about 4 feet (1.4 m) tall when standing erect, and weighs up to 200 pounds (90 kg). The female is smaller and weighs about 90 pounds (40 kg). The orangutan has a sloping forehead; small, rounded ears; a short, stout body; and short legs. It has no tail. It is covered with red or reddish-brown brown shaggy hair. There are bald patches on the forehead and shoulders, and around the mouth. Old males have protruding areas of skin on their cheeks, which make their faces appear broad.
The orangutan has long arms, small ears, a stout body, and short legs.Orangutans spend most of their lives in trees. They use their long, powerful arms to swing from one branch to another. Their thumbs and big toes are opposable, allowing them to grasp things with their hands and feet. Orangutans feed mainly on fruit, insects, and leaves. At night they gather leaves and twigs and build a large platform-like nest on which they sleep. Orangutans typically live alone or in small groups. The female gives birth to a single offspring after a gestation period of eight to nine months. The young orangutan is carried on the mother's back for about a year. It is usually weaned after two years. Orangutans reach sexual maturity at the age of seven or eight. Their average life span is 30 years.
Due to commercial logging and illegal hunting, the orangutan is an endangered species.
The orangutan is Pongo pygmaeus of the great ape family, Pongidae.
Which Apes Are Loners?
Orangutans are loners. Unlike other great apes, they spend most of their time by themselves.
Scientists think that orangutans spend most of their time alone because of their feeding needs. Orangutans eat mainly figs and other fruit. Often, too little food is available at any one spot to feed a whole group or to feed even a single orangutan for very long. Therefore, an orangutan must be always on the move, looking for the next source of ripened fruit for itself and any youngsters it has. However, at times when ripe fruit is plentiful, several orangutans have been seen eating peacefully in the same tree.
Sometimes, orangutans will meet each other by chance as they wander through the treetops. When two males meet, the stronger will drive the other away. When females meet, the encounter is nearly always peaceful.
Where Do Orangutans Spend Most of Their Time?
Unlike gorillas, chimpanzees, and bonobos, orangutans spend most of their day high up in the trees. Orangutans are the largest tree-living animals in the world.
As they travel high above the forest floor, orangutans make little noise. It is hard to spot and study them because they move so silently and are usually high above the ground. Their reddish-brown hair blends in with brown tree trunks and branches. They rest or nap for hours at a time without moving, which also makes them hard to find.
Orangutans move awkwardly when they are on the forest floor. When walking on all fours, chimpanzees and gorillas use their knuckles for support. Orangutans, however, support their upper bodies with closed fists. Sometimes orangutans will walk upright, too. And they tend to walk on the outside edges of their feet, not flat on the soles, because they have long, curved toes.
Do Male and Female Orangutans Look Alike?
An adult male orangutan is twice the size of an adult female of the species. In addition to the difference in size, the face of a male and the face of a female are different, too. A mature male orangutan has broad cheek pads that jut out from the sides of his face. He also has a large throat pouch. A female has no cheek pads and only a small throat pouch.
Researchers aren’t quite sure what purpose the cheek pads serve. But the throat pouch amplifies an orangutan’s voice, which is useful when the male makes a “long call”—a series of roars to remind others that he owns a territory. Long calls can be heard more than 1⁄2 mile (0.8 kilometer) away.
Both male and female orangutans have red hair in varying shades. Because of their red hair, orangutans look very different from the other apes.
How Is An Orangutan’s Body Suited For Living In Trees?
An orangutan has extremely long arms, compared with its legs and upper body. Its arms reach to its ankles when it is standing upright. It has long, curved fingers and toes that help it grasp branches, and its shoulder joints and hip joints are remarkably flexible.
Orangutans can walk on the ground, but they rarely do so. When they do, they walk on all four limbs, slowly and cautiously, and they usually only walk as far as the distance from one tree to the next. They travel much more gracefully when swinging from branch to branch in the trees.
Because they live so dangerously high in the trees, a mother orangutan must be careful with her offspring. At first, an infant simply holds on as tight as it can to its mother. Soon, however, the mother encourages her young to climb. She usually stays within arms’ reach until the young orangutan builds its strength.