Chimpanzee

The chimpanzee (/ˌtʃɪmpænˈziː/; Pan troglodytes), also simply known as the chimp, is an endangered species of great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close relative, the bonobo, was more commonly known as the pygmy chimpanzee, this species was often called the common chimpanzee or the robust chimpanzee. The chimpanzee and the bonobo are the only species in the genus Pan.

The chimpanzee is covered in coarse black hair but has a bare face, fingers, toes, palms of the hands, and soles of the feet. It is larger and more robust than the bonobo, weighing 40–70 kg (88–154 lb) for males and 27–50 kg (60–110 lb) for females and standing 150 cm (4 ft 11 in). Evidence from fossils and DNA sequencing shows that Pan is a sister taxon to the human lineage and is thus humans' closest living relative.

The chimpanzee lives in groups that range in size from 15 to 150 members, although individuals travel and forage in much smaller groups during the day. The species lives in a strict male-dominated hierarchy. Nearly all chimpanzee populations have been recorded using tools, modifying sticks, rocks, grass and leaves and using them for hunting and acquiring honey, termites, ants, nuts and water. Its gestation period is eight months. The infant is weaned at about three years old but usually maintains a close relationship with its mother for several years more.

Etymology

The name "chimpanzee" was first used in 1738 in The London Magazine. It meant "mockman" in a language from Angola. The shorter word "chimp" started being used in the late 1870s.

The scientific name for chimpanzees, Pan troglodytes, comes from old stories. "Pan" is the name of a Greek god. "Troglodytes" refers to a mythical group of people who lived in caves.

Taxonomy

The chimpanzee was first recognized in the 17th century. Early scientists studied chimpanzees and their close relatives, the bonobos. By the late 1700s, German naturalist Johann Friedrich Blumenbach named the chimpanzee Simia troglodytes. In 1816, another German naturalist, Lorenz Oken, introduced the genus Pan.

Chimpanzees, along with humans, belong to the Hominidae family, also called the great apes. This family includes orangutans, gorillas, chimpanzees, bonobos, and humans. Studies show that chimpanzees and humans share a common ancestor and have very similar DNA, differing by only about 1.2%. Chimpanzees have 24 pairs of chromosomes, while humans have 23 pairs.

Characteristics

Adult chimpanzees stand about 150 cm (4 ft 11 in) tall on average. Males usually weigh between 40 and 70 kg (88 and 154 lb), while females weigh between 27 and 50 kg (60 and 110 lb). They have long arms that can reach below their knees, and their hands and feet are made for grasping. Their faces are rounded with eyes that face forward and prominent brow ridges.

Chimpanzees are covered in coarse hair except on their faces, hands, and feet. Their hair is usually black but can be brown or ginger, and may turn white or grey with age. They are strong climbers and can walk on all fours or on two legs. Their brains are smaller than human brains but are built for quick actions.

Ecology

The chimpanzee is an adaptable animal. It can live in many kinds of places, like dry savanna, evergreen rainforest, montane forest, swamp forest, and woodland. Chimpanzees build a new sleeping nest in a tree every night. They usually sleep alone, except for babies and young chimpanzees who stay with their mothers.

Chimpanzees eat many different foods but like fruit best. They also eat leaves, seeds, blossoms, stems, and some insects and small animals. Fruits and other plant foods are the main part of their diet. What they eat can change depending on where they live and what food is available.

Behaviour

Chimpanzees live in groups. These groups can have up to 150 members, but they usually travel in smaller groups. These groups can include people of any age and sex, and both males and females sometimes travel alone. Males stay in the group where they were born, while females usually leave when they are older. Males are usually dominant over females.

Chimpanzees talk to each other using faces, sounds, and body moves. They make special faces and sounds to show when they are scared, playing, or being quiet. They also make calls to stay in touch with their group and to tell about danger or food.

Hunting for food is done by males together, while females often hunt alone. Chimpanzees work as a team to catch monkeys, with each member having a specific job in the hunt.

Intelligence

Further information: Primate cognition

Chimpanzees are very smart. They can remember symbols, use tools, and work together. They have passed the mirror test, which shows they know themselves. Chimpanzees can remember things even after a long time. They use insects to help heal wounds and have behaviors that look like culture, like different ways of grooming or using tools.

Chimpanzees can learn to recognize numbers and remember quick flashes of digits. One chimpanzee named Ayumu was very good at this, doing better than human adults in some tests. They also make sounds like laughter when playing or being tickled.

Tool use

Further information: Tool use by animals

Almost all chimpanzee groups use tools. They change sticks, rocks, grass, and leaves to help catch food like termites, ants, nuts, and honey. Some chimpanzees have used stone tools for over 4,000 years.

One famous chimpanzee changed a twig to get termites from their homes. Others use sticks to get honey from beehives, and some use leaves to drink water. In West Africa, chimpanzees sharpen sticks to catch small animals from tree holes.

Speech and language

Main article: Great ape language

Scientists have tried to teach chimpanzees human language. One chimpanzee named Washoe learned many signs for things. Another chimpanzee named Nim Chimpsky learned signs too, but later studies showed he mostly copied what humans did.

Human relations

Chimpanzees appear in many stories and shows. Some African groups, like the Gio people of Liberia and the Hemba people of the Congo, make chimpanzee masks for teaching. In Western shows, chimpanzees are often shown as fun friends, like Judy on Daktari and Darwin on The Wild Thornberrys. They are also in science fiction stories, such as Conquest of the Planet of the Apes.

Some chimpanzees have been kept as pets, but this can be risky because they are very strong. Chimpanzees have also been in research to help us learn about health. Famous work by Jane Goodall at Gombe Stream National Park showed us much about how chimpanzees live and feel. These studies show that chimpanzees have deep feelings and strong friendships.

Conservation

The chimpanzee is an endangered species. There are fewer chimpanzees now than in the past. They live in national parks and other protected areas.

The biggest dangers to chimpanzees are losing their homes, poaching, and diseases. Their forests are shrinking because of deforestation and road building. Some people hunt chimpanzees for food or take them as pets. Diseases are a problem because chimpanzees and humans can catch the same illnesses.