Sous la Direction du Prof. Ronald Noë, un groupe des chercheurs internationaux recherchent le comportement des singes du Parc National de Taï. Trouvez ici les résumés de quelques chercheurs de ce groupe, mis a la disposition de la Direction du Parc.
Friedericke Range : système sociale des mangabés
Paul Buzzard : Compétition intraspecifique entre trois espèces des singes.
The cognitive capacities of non-human primates pose an intriguing problem
for evolutionary theory. The large primate brain (compared to body size) is
energetically costly to develop and thus its possession is expected to bring
about a considerable fitness advantage. Several hypotheses have been proposed
to explain why the large neo-cortex in the primate brain evolved. One approach
suggests that the brain evolved to process information of ecological relevance,
for example searching for resources in the home range ('mental map') or recognizing
and locating specific food items in the environment (Clutton-Brock, 1980).
An alternative hypothesis suggests that the primate brain evolved as an adaptation
to cope with social complexity such as kinship networks, friendships, dominance
hierarchies and formation of alliances (see Dunbar, 1998 for a concise review).
Knowing that complex social structures exist in most non-human primate species,
questions arise about the proximate cognitive mechanisms driving behavior,
and more specifically the nature of the underlying mental representations.
The complex behavior we observe could be the result of relatively simple stimulus
response rules or associative contingencies where animals have knowledge about
others based on prior observations. Alternatively, primates could have a "declarative
representation" of the world meaning that they can recognize relations
among other group members and understand concepts like dominance, kinship
and reciprocity. The latter hypothesis implies a more abstract knowledge that
would allow for greater flexibility in behavior depending upon changes in
the social and ecological environment and the ability to make statements and
causal inferences. Some experimental and field studies show that primates
engage in a number of complex interactions that demonstrate an understanding
of third-party relationships implying at least some kind of knowledge about
dominance and kinship relationships. However, the question is if monkeys really
have an abstract, conceptually knowledge of relationships or if an individuals
knows each of the third parties involved as individuals and remembers something
of their past interactions with each other.
This study on sooty mangabeys in the Tai National Park focuses on the social brain hypothesis. Sooty mangabeys, a terrestrial and highly social forest species, live in large groups up to 120 individuals with 25-30 adult females and 10-15 adult males. Females establish linear and stable dominance hierarchies, form close and well-differentiated relationships with each other, and do not emigrate from their natal group, while males exhibit an unstable social structure where some males join the group only for a few days every month. Using observation and playback experiments on sooty mangabeys, specific aspects of social knowledge within a group of sooty mangabeys and between neighboring sooty mangabeys groups are tested. The following questions are posed:
What knowledge of social relationships do sooty mangabeys posses and how do they use it? Do sooty mangabeys understand dominance relationships and can they make transitive inferences? What do mangabeys know about third-party relationships in relation to subgroup membership? Are sooty mangabeys able to distinguish between vocalizations of familiar individuals and strangers? How and when do they use vocal communication? Retour
Range, F. & Noë, R, in press, Familiarity and dominance relations among female sooty mangabeys in the Taï National Park. American Journal of Primatology.