Ape, any of 13 species of tailless primates. The orangutan, gorilla, chimpanzee, and pygmy chimpanzee are the largest apes and are called great apes. Gibbons are the smallest apes and are called lesser apes. The gorilla, chimpanzee, and pygmy chimpanzee live in Africa. Orangutans and gibbons live in Asia.

The orangutanThe orangutan is a great ape native to Asia.

Apes resemble humans so closely that they are referred to as anthropoid (humanlike). Apes have large brains and are among the most intelligent animals. An ape's skeleton is similar to that of a human. However, relatively shorter legs and longer arms make apes better adapted for tree-dwelling and walking on all fours than for standing erect. Apes have short, coarse fur and rounded ears; there is little or no hair on the face and ears. They usually live in family or multi-family groups, although orangutans are also found singly or in pairs. The female usually gives birth to one offspring at a time. Apes feed chiefly on vegetation; they also eat eggs, insects, birds, and small mammals.

Where in the World Do Gorillas and Other Apes Live?

Gorillas live in the tropical lowland forests of western and central Africa. They also live in the mountain forests of eastern Africa. Bonobos live in a section of African rain forest south of the Congo River in Congo (Kinshasa). Chimpanzees live in a wide range of habitats from western to eastern Africa.

Apes also live in Asia. Orangutans live in the tropical forests on the islands of Borneo and Sumatra in Southeast Asia. Gibbons live in the forests of India and in Southeast Asia.

How Do Apes Measure Up?

Gorillas are the largest members of the ape family. A large male gorilla can weigh 390 pounds (177 kilograms). Standing up on its legs, it might be 6 feet (1.8 meters) tall. Females weigh about 200 pounds (91 kilograms) and are shorter than males. In contrast to gorillas, gibbons—the smallest members of the ape family—each weigh about 15 pounds (7 kilograms) and are about 3 feet (0.9 meter) tall.

A male orangutan weighs about 180 pounds (82 kilograms) and stands about 4 1⁄2 feet (1.4 meters) tall. Females are about half as large.

What’s So “Great” About the Great Apes?

Primarily, it’s their size. “Great apes” include bonobos, chimpanzees, gorillas, and orangutans. Gibbons, which are much smaller than the others, are called “lesser apes.” In addition to their size, there are other special things about great apes. They rank as the most intelligent animals after human beings. Some apes—chimpanzees in particular—use tools in some of the same ways humans do. For example, chimpanzees use stones to crack open the shells of hard nuts. Then they can then eat the nuts that were held inside. In addition, laboratory researchers have been able to teach chimps to perform tasks and to communicate with humans.

What’s Under All That Hair?

Apes have strong bones and powerful muscles. Their body structure is more like a human’s than that of any other animal. Apes and humans have similar bones, muscles, and organs. But apes walk on four limbs and have shorter legs and more body hair than humans.

Both humans and apes have highly developed nervous systems and large brains. Like humans, apes rely on their excellent eyesight for much of their information about their environment. They have large eyes and stereoscopic vision. This means that they have the ability to see depth.

Again, like humans, apes have opposable thumbs. This means that their thumbs can be placed opposite their fingers so that they can grasp objects. Apes also have nails instead of claws on their fingers and toes.

Do Other Apes Live and Travel in Groups?

Scientists believe that chimpanzees form loosely tied groups called communities. Members of a community share the same territory, or home range. Within these communities, the apes travel alone or in smaller groups that vary in number and change members often. Males and females within a community have almost complete freedom to come and go as they wish. Each chimpanzee has its own companions.

There are three types of groups: (1) all male bands, (2) bands of mothers and their infants, and (3) mixed bands of both male and female chimpanzees. One or more males usually control a group’s territory.

Bonobos, which are closely related to chimpanzees, also form communities. Within a bonobo community there are social groups of 7 to 10 members (both males and females).

How Have People Learned About Apes?

Scientists study apes both in captivity and in the wild. Some researchers spend many years of their lives living among wild apes in their native habitat and carefully watching their behavior.

Louis Leakey (1903–1972) was a British anthropologist (a scientist who studies humanity and human culture) who searched in Africa for evidence of the earliest human beings. He also helped three women—Jane Goodall, Dian Fossey, and Biruté Galdikas—conduct detailed research of great apes living in their natural habitats.

Jane Goodall (1934–), a British zoologist, began working with chimpanzees in the wild in 1960. Most of her study has taken place in northwestern Tanzania. Dian Fossey (1932–1985) was an American zoologist who began studying mountain gorillas in east-central Africa in 1966. Biruté Galdikas (1946–), a Lithuanian-born Canadian anthropologist, began studying orangutans in Borneo in 1971.

Are Apes in Danger?

Most kinds of apes are in danger of extinction (the dying off of all their kind). Today, there are believed to be about 400,000 great apes in Africa and Asia, compared with many millions in the 1800’s. Without help, some species of apes may die off completely in our lifetime—in 50 or fewer years.

Sadly, it is the apes’ closest relatives—human beings—who pose the greatest threat to their survival. Humans destroy the habitat of these creatures by clearing forests to build homes, establish farms, and sell wood. People capture these animals for sale to zoos and research centers, to be kept as pets, and for the sale of parts of their bodies. Apes are also hunted for food.

But humans also offer the greatest hope for saving the apes. The United Nations—an organization of nations working for world peace and security—has created a plan to help protect the apes. The United Nations hopes to educate people about the risks of ape extinction and the benefits of preserving ape habitats.

Apes belong to the order Primates. The great apes make up the family Pongidae. Gibbons are in Hylobatidae. Bonobos and chimpanzees are genus Pan, gorillas are genus Gorilla, and orangutans are in the genus Pongo. Gibbons, except for the siamang, are genus Hylobates. Siamang is genus Symphalangus.