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Pan troglodytes [pan' trog luh dI' tEz]
An adult male chimpanzee has a head and body length of 30 to 36 inches and weighs up to 200 pounds. Females are slightly smaller, being 28 to 38 inches long and weighing up to 180 pounds. Overall height ranges from 3 to 5.5 feet, and the arm spread is 50% greater than the height.
Most of the body is covered with long, coarse black or brown hair, but the face, ears, fingers and toes are bare. As with humans, baldness is quite common among mature chimpanzees, except that females tend to experience it worse than males.
Chimpanzees have hands that can grip firmly, thanks to an opposable thumb.
Distribution and Habitat
Chimpanzees live in the tropical rain forests of western and central equatorial Africa. They are at home in the trees, but often come down to the ground to search for food.
Chimpanzees live in groups numbering from 15 to 140 individuals. The size of a group will increase as chimpanzees gather at a source of plentiful food, and will decrease as that source depletes, and individuals move between groups frequently. The only constant unit of social life is a mother with her young. She may have two or three of different ages with her at any time because they stay with her for several years.
Within a party, the males are arranged in a social order, based primarily on age.
Chimpanzees are very "touchy-feely," often kissing and/or "shaking hands" when they meet. They also communicate with each other using a wide range of facial expressions and vocalizations.
There is no regular breeding season, but females only mate during heat, which lasts two to three weeks and occurs every four to six weeks. During this time females are quite promiscuous and will mate with any willing male.
A single baby -- twins are rare -- is born after about 230 days. The quality of baby care shown by female chimpanzees varies considerably -- from overly attentive and protective to neglectful. In general, however, the standard of care and education for chimpanzee young is among the highest in the animal kingdom. In addition, chimpanzee babies are among the most obedient children in the animal kingdom, although juvenile delinquency is not unheard of.
An infant can sit up at about 5 months and stand with support at 6 months. It will be totally dependent upon its mother until reaching about 2 years of age, and will remain with her until about 3 years old. Sexual maturity is reached between 7 and 10 years of age.
Chimpanzees spend up to 7 hours a day feeding, and will investigate virtually any source likely to produce food. Crevices in logs are searched for insects and nests are robbed of eggs and chicks, but their usual food consists of fruits, leaves and roots. Ripening fruit crops are a special attraction to them and bands of chimpanzees have been known to do considerable damage to plantations before the ripened fruit can be harvested.
While 90-95% of the chimp's diet consists of plant matter and insects, it is not at all unusual for an individual chimpanzee to hunt down, kill and eat small monkeys, pigs, or even antelope.
The chimpanzee is one of the very few animals known to make and use tools in the wild. Twigs and vines are stripped of leaves and then used to "fish" for termites. A stick may be used to enlarge the hole in an ant hill. Leaves are chewed to make them more absorbent so that they can be used to dip for water in holes in trees. And, every night, each chimp constructs a nest of vegetation in which to sleep. What makes tool use among chimpanzees even more remarkable is the fact that individual chimpanzees have been seen showing other individuals how to make and use implements, and that the quality of tool-making within a family group may actually improve over the course of a few generations.
In a classic experiment a
chimpanzee was faced with the challenge of getting to a
bunch of bananas hanging from the ceiling. With little
hesitation, the chimp stacked the three wooden crates
that the observer had "conveniently left
behind," climbed to the top of the stack, and got
Chimpanzees have also been observed using medicinal plants to treat themselves and others for illness and injury.
Individual chimpanzees can recognize themselves in a mirror -- as opposed to seeing the reflection as another animal.
Chimpanzees avoid water at all costs and are usually unable to swim.
This page was last updated on February 21, 2017.