face of adults is typically black, or mottled with brown. Hair
is black to brown, and there is no underfur present. There may
be some white hairs around the face (looking a bit like a white
beard in some individuals). Infants have a white tuft of hair
on their rumps, which identifies their age quite clearly. This
white tail tuft is lost as an individual ages. Individuals of
both sexes are prone to lose the hair on the head as they age,
producing a bald patch behind the brow ridge. Graying of hairs
in the lumbar region and on the back is common with age, also.
have a head and body length ranging between 635 and 925 mm.
When standing erect, they are 1 to 1.7 m tall. In the wild,
males weigh between 34 and 70 kg, whereas females are slightly
smaller, weighing between 26 and 50 kg. The arms are long, such
that the spread of the arms is 1.5 times the height of an individual.
Legs are shorter than are the arms, which allows these animals
to walk on all fours with the anterior portion of the body higher
than the posterior. They have very long hands and fingers, with
short thumbs. This hand morphology allows them to use their
hands as ³hooks² while climbing, without interference from the
Chimpanzees are broadly omnivorous. They rely heavily on ripe
fruits and young leaves, with additional consumption of stems,
buds, bark, pith, seeds, and resins. This diet is supplemented
by a variety of insects, small vertebrates, and eggs. Soil is
sometimes consumed, especially that associated with termite
mounds, presumably for the minerals it contains. Diets vary
seasonally, as different foods are available at different times
have an estrus cycle which lasts approximately 36 days. During
the course of this cycle, as her hormone levels change, a female
experiences changes is the size, shape, and color of her genital
skin. As circulating estrogens increase during the follicular
phase of the cycle, the size of the swelling increases. When
the anogenital skin is fully engorged, it is typically bright
pink, and can measure from 938 to 1400 cc. The state of maximal
tumescence is of variable length in different individuals and
at different stages of maturity, but lasts an average of 6.5
days. It is during this time that females are sexually receptive
and that the bulk of copulations with mature males occur.
utilize a great diversity of habitat types. Although they are
typically thought of as living in tropical rainforests, they
are also found in forest-savanna mosaic environments, as well
as in montain forests at elevations up to 2,750 m. Some populations
are known to inhabit primarily savanna habitat. Most
Pan troglodytes inhabit the tropical forests of central
are three recognized subspecies of Common Chimpanzee.
are found in S Cameroon; Gabon; S Republic of Congo; Uganda;
W Tanzania; E and N Dem. Rep. Congo; W Central African Republic;
Guinea to W Nigeria, south to Congo River in W Africa.