Gestural signalling in bonobos (Pan paniscus ), chimpanzees (Pan
troglodytes) and gorillas (Gorilla gorilla): a comparison

Simone Pika(1), Michael Tomasello(2)
(1)University of Alberta, Edmonton, Canada
(2)MPI for evolutionary Anthropology, Leipzig, Germany

email: pika@eva.mpg.de


The primary goal of the present study was to enhance the knowledge and
understanding of gestural communication concentrating on our closest
living relatives, the apes.  The present study is based on observations
of Tomasello and colleagues [1994; 1997; 1985; 1989] on the gestural
signalling of a group of captive chimpanzees (Pan troglodytes) and
observations of two groups of gorillas (Gorilla gorilla) and two groups
of bonobos (Pan paniscus) in captivity.  Our goal was to compile the
gestural repertoire of gorillas and bonobos and to focus on processes
underlying social cognition, including learning mechanisms and the
flexibility of gestural use, such as the adjustment to the attentional
state of the recipient.  The results enabled us to draw inter- and
intra-species comparisons.  The most intriguing differences between the
three species become obvious concentrating on, 1) gestures in the sexual
context, 2) the average number of gestures used, and 3) the variety of
auditory gestures. 

These differences seem to indicate general communication differences
between the three ape species and are discussed in relation to their
different ecological settings and social systems. 

Keywords: gestures, learning, use, Pan paniscus, Pan troglodytes,
Gorilla gorilla. 

References

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Tomasello M, Call J, Warren J, Frost T, Carpenter M, Nagell K.  1997. 
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Tomasello M, George BL, Kruger AC, Farrar MJ, Evans A.  1985.  The
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Tomasello M, Gust D, Frost GT.  1989.  A longitudinal investigation of
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