The hair on the head may grow in many directions, and both sexes are prone to partial baldness early in maturity. Males are larger and stronger than females, and have bigger canine teeth which they use in severe fights. Body proportions are otherwise similar, but both sexes have prominent genitals. The Common chimpanzee is found north of the River Zaire. They live not only in humid closed-canopy forests but also in relatively dry areas, such as flat savanna.
Chimpanzees have similar sensory abilities to people.
Their large brains reflect a consistently high performance on all intelligence tests devised by humans, including the ability to learn and use words defined by hand signals in languages used by the deaf. Adults sleep alone, infants with their mothers until the next sibling is born. Chimpanzees use tools to solve a greater range of problems, than any animal apart from humans. Sticks or soft stems are use to get ants and other insects by inserting them into holes. They also use sticks or rocks to break open fruits with shells too hard to bite open.