The
home range of the Bossou chimpanzees is clearly dominated by secondary
and scrub forest, with primary forest only covering about 1 sq. km.
It is additionally surrounded by savanna vegetation interspersed with
occasional gallery forests, which connect to small adjacent forests,
beyond which lie, on the southeastern side, the Nimba Mountains. The
Bossou chimpanzees mostly confine their daily activity within a core
area of about 6 sq. km, though they sometimes travel to adjacent forests
using the few remaining gallery forest corridors that extend their home
range to around 15 sq. km.
Behaviors of chimpanzees
Road-crossing
in chimpanzees: a risky business
The home range is dissected by a narrow road (3m wide) which
is used by pedestrians and a newly expanded larger road (12m wide at
the crossing point), which carries trucks, cars, motorbikes and pedestrians.The
roads are forested up to the edge and separated by secondary forest
and plantations.
Road-crossing presents a new situation that calls for flexibility
of responses by chimpanzees to variations in perceived risk. The chimpanzees
at Bossou, Guinea, West Africa, employ a phylogenetically-old mechanism
to adapt to a more recent dangerous situation. The positioning of dominant
and bolder individuals, in particular the alpha male, changed depending
on both the degree of risk and number of adult males present; dominant
individuals act cooperatively with a high level of flexibility to maximise
group protection. Differences in progression orders may reflect the
division of roles, and the collaboration among males to protect the
females and their off-spring. This may also help shape hypotheses about
emergence of hominoid adaptive social organization.
NEW
ARTICLE
Hockings,K.,Anderson,J.,& Matsuzawa,T(2006) Road crossing in chimpanzees:
A risky business Current Biology,16, 668-670.
Video clip is here.
You can see the chimpanzees crossing the large
road in front of on-looking villagers.
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Tool using
Different communities of wild chimpanzees possess different
tool use repertoires. However, not all of this regional and local variation
can be explained by the demands of the physical and biotic environments
in which they live. Many of these behavioral variants are socially learnt
and are maintained from one generation to the next. These have now been
acknowledged as representing cultural behaviors (Whiten et al, 1999).
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Crop-raiding in Bossou
The
chimpanzee totems of Bossou
Sometimes Bossou chimpanzees come to the village to eat papaya.
FOAF (adult male) up a virtually dead papaya tree.
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