Primate Social Organization 83Individual Interaction and Bonding
The social sophistication characteristic of primates is evi-
dent in behaviors that at first glance might seem wholly
practical. For example, grooming, the ritual cleaning of
another animal to remove parasites and other matter from
its skin or coat, is a common pastime for both chimpan-
zees and bonobos. The grooming animal deftly parts the
hair of the one being groomed and removes any foreign
object, often eating it. But besides serving hygienic pur-
poses, it can be a social gesture of friendliness, closeness,
appeasement, reconciliation, or even submission.
Bonobos and chimpanzees have favorite groom-
ing partners. Group sociability, an important behavioral
trait undoubtedly also found among human ancestors, is
further expressed in embracing, touching, and the joyous
welcoming of other members of the ape community.
Interestingly, different chimp communities have dif-
ferent styles of grooming. In one East African group, for
example, the two chimps groom each other face to face,
with one hand, while clasping their partner’s free hand.
In another group 90 miles distant, the hand clasp is un-
known. In East Africa, all communities incorporate leaves
in their grooming, but in West Africa they do not.
Gorillas, though gentle and tolerant, are also aloof
and independent, and individual interaction amonggrooming The ritual cleaning of another animal’s coat to
remove parasites and other matter.our case, the stipulation that the reunion
happen not long after the conflict. There
is no intrinsic reason that a reconciliation
could not occur after hours or days, or, in
the case of humans, generations.
Let me describe two interesting elab-
orations on the mechanism of reconcilia-
tion. One is mediation. Chimpanzees are
the only animals to use mediators in con-
flict resolution. In order to be able to me-
diate conflict, one needs to understand
relationships outside of oneself, which
may be the reason why other animals fail
to show this aspect of conflict resolution.
For example, if two male chimpanzees
have been involved in a fight, even on a
very large island as where I did my stud-
ies, they can easily avoid each other, but
instead they will sit opposite from each
other, not too far apart, and avoid eye
contact. They can sit like this for a long
time. In this situation, a third party, such
as an older female, may move in and try
to solve the issue. The female will ap-
proach one of the males and groom him
for a brief while. She then gets up and
walks slowly to the other male, and the
first male walks right behind her.
We have seen situations in which, if
the first male failed to follow, the female
turned around to grab his arm and make
him follow. So the process of getting the
two males in proximity seems intentional
on the part of the female. She then
begins grooming the other male, and the
first male grooms her. Before long, the
female disappears from the scene, and
the males continue grooming: She has in
effect brought the two parties together.
There exists a limited anthropological
literature on the role of conflict resolu-
tion, a process absolutely crucial for the
maintenance of the human social fabric
in the same way that it is crucial forour primate relatives. In human society,
mediation is often done by high-ranking
or senior members of the community,
sometimes culminating in feasts in
which the restoration of harmony is
celebrated.c
The second elaboration on the recon-
ciliation concept is that it is not purely
instinctive, not even in our animal rela-
tives. It is a learned social skill subject
to what primatologists now increasingly
call “culture” (meaning that the behav-
ior is subject to learning from others
as opposed to genetic transmission).d
To test the learnability of reconcilia-
tion, I conducted an experiment with
young rhesus and stumptail monkeys.
Not nearly as conciliatory as stumptail
monkeys, rhesus monkeys have the
reputation of being rather aggressive
and despotic. Stumptails are considered
more laid-back and tolerant. We housed
members of the two species together
for 5 months. By the end of this period,
they were a fully integrated group: They
slept, played, and groomed together.
After 5 months, we separated them
again, and measured the effect of their
time together on conciliatory behavior.
The research controls—rhesus mon-
keys who had lived with one an other, with-
out any stumptails—showed absolutely
no change in the tendency to reconcile.
Stumptails showed a high rate of reconcil-
iation, which was also expected, because
they also do so if living together. The most
interesting group was the experimental
rhesus monkeys, those who had lived with
stumptails. These monkeys started out at
the same low level of reconciliation as the
rhesus controls, but after they had lived
with the stumptails, and after we had seg-
regated them again so that they were now
housed only with other rhesus monkeyswho had gone through the same experi-
ence, these rhesus monkeys reconciled
as much as stumptails do. This means
that we created a “new and improved”
rhesus monkey, one that made up with its
opponents far more easily than a regular
rhesus monkey.e
This was in effect an experiment on
social culture: We changed the culture of
a group of rhesus monkeys and made it
more similar to that of stumptail monkeys
by exposing them to the practices of this
other species. This experiment also shows
that there exists a great deal of flexibility
in primate behavior. We humans come
from a long lineage of primates with great
social sophistication and a well-devel-
oped potential for behavioral modification
and learning from others.ade Waal, F.B.M. (2000). Primates: A
natural heritage of conflict resolution.
Science 28, 586–590.
bAureli, F., & de Waal, F.B.M. (2000).
Natural conflict resolution. Berkeley:
University of California Press.
cReviewed by Frye, D. P. (2000).
Conflict management in cross-cultural
perspective. In F. Aureli & F.B.M.
de Waal, Natural conflict resolution
(pp. 334–351). Berkeley: University of
California Press.
dFor a discussion of the animal culture
concept, see de Waal, F.B.M. (2001).
The ape and the sushi master. New
York: Basic.
ede Waal, F.B.M., & Johanowicz, D. L.
(1993). Modification of reconciliation
behavior through social experience: An
experiment with two macaque species.
Child Development 64 , 897–908.