New paper on sociality in eastern and western chimpanzees

Western chimpanzee party engaged in grooming. Photo credit: Dr. Kathelijne Koops

Flexibility in chimpanzee grouping patterns

In this new paper, researchers used the same motion-triggered camera technology to compare party size and composition between the western Gahtoy community in the Nimba Mountains (Guinea) and the eastern Waibira community in the Budongo Forest (Uganda). Party size in western and eastern chimpanzees did not differ between our two study communities suggesting that the number of individuals in a party is shaped by similar socio-ecological pressures. Eastern chimpanzees were found to have more males in a party compared to western chimpanzees, contrary to the expectation of more female-only parties in eastern compared to western chimpanzees. These findings highlight the flexibility in chimpanzee grouping patterns and caution against subspecies level generalizations from limited data points and/or heterogeneous methods. This comparative study was co-led by APE Group’s Kathelijne Koops and Cat Hobaiter from Wild Minds Lab at the University of St Andrews.

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