Hunting, Tools, and Sociality: A new
evolutionary scenario for chimpanzees and humans
Boesch Christophe
Max Planck Institute for Evolutionary Anthropology
Leipzig, Germany
Carnivorouschimpanzee indigenous
in the Taï Forest, Ivory Coast |
Chimpanzees and humans possess in
common three behavioural properties that distinguish them from
the rest of the primates and mammals: They are the only species
in which all know living populations use regularly many different
types of tools, hunt regularly at least a few mammal species
for meat, and live in large groups with a flexible fission-fusion
social structure. If some models of human evolution have considered
one or two of these behavioural patterns, none has stressed the
importance of the simultaneous presence of the three of them
within the chimpanzee-human clade. I propose here an evolutionary
scenario of the evolution in chimpanzees and humans of these
three abilities and explain how this was possible thank to the
appearance of new cognitive capacities in this clade.
For flexible tool use and hunting to
evolve, the acquisition of a more elaborate understanding of
causality as well as some notions of a theory of mind is required.
These cognitive abilities progressively appeared in our common
ancestors when they started to hunt arboreal prey for meat within
flexible fission-fusion social groups. The flexibility required
to live in a fission-fusion social structure was an important
precondition for the acquisition of an elaborate understanding
of causality and for being able to adopt the perspective of the
prey within trees, both abilities essential to hunt successfully.
Once those cognitive abilities are acquired, it became possible
to anticipate the benefit of tool use in novel situations, which
led to both a more flexible tool repertoire and more complex
tool uses.
Boesch, C. and Boesch-Achermann, H. 2000. The Chimpanzees
of the Taï Forest: Behavioural Ecology and Evolution. Oxford:
Oxford University Press.