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In-Depth Information
The primate social field
The primate family tree split up about forty million years ago into prosimi-
ans, which might resemble early arboreal primates (e.g. lemurs), and anthro-
poids (monkeys, apes, incl. humans). The problems of social life are especially
complex for species whose cognitive skills create a complex
social field
which is
based on several fundamental components:
1.
Individuals specifically recognize other conspecifics in their groups as indi-
viduals and as kin. Primate societies are
individualized societies
.Thesocial
world of primates is primarily vision-dominated, recognition of friends
and relatives and their behavior is therefore strongly based on visual cues,
e.g. faces need to be recognized and memorized.
Two separate mechanisms have been proposed for kin-recognition: early
familiarity (i.e. previous experience with the individuals in question) and phe-
notypic matching (using visual or non-visual cues). Generally, it is assumed
that kin recognition in primates depends on previous experience. However,
chimpanzees have been shown to be able to match related but unknown indi-
viduals by visual cues, in the same way as humans can match persons in a family
album. In the wild, chimpanzees form loosely organized fission-fusion com-
munities where even closely related individuals spend considerable time apart.
Under such conditions phenotypic kin recognition could be greatly advanta-
geous. As Parr and de Waal showed (Parr et al. 1999), chimpanzees can per-
ceive similarities in the faces of related but unfamilar individuals, indicating vi-
sual kin recognition at a purely phenotypic level. Their results show that chim-
panzees can match very well faces of mothers and their sons, but not mother-
daughter pairs. This preference might be due to the particular ecological and
social conditions of chimpanzee life.
How individual recognition substantially increases social complexity is
shown by the following example described in (Philips & Austad 1996: 265):
“...imagine a social group composed of six individuals, two unrelated sets of
three full siblings. Consider an individual within that group seeking to join
two other individuals for the purposes of cooperative hunting. With recog-
nition only of group members versus nongroup members, there is only one
recognizable hunting group - himself plus two other group members. If kin-
ship were also recognized, then this individual could discriminate between
three kind of groups (two fellow sibs, two nonsibs, one sib and one nonsib). If
all group members were individually recognizable, our focal individual could
potentially join twenty unique groups.”
