The 85th Annual Meeting of the American Association of Physical Anthropologists (2016)


Rethinking chimpanzee tool use: Niche construction and developmental bias in maintaining technological traditions among African apes

CRICKETTE M. SANZ1,2 and DAVID B. MORGAN2,3.

1Department of Anthropology, Washington University, 2Congo Program, Wildlife Conservation Society, 3Lester Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo

April 15, 2016 8:45, Imperial Ballroom B Add to calendar

Understanding the differences in technological skills among hominids has proven a formidable challenge for biological anthropologists. Examining the environment as a background condition for the vast degree of behavioral diversity observed within the clade of African apes has proven insufficient in explaining some of the most interesting and salient differences among our closest living relatives. In this study, we employed the extended evolutionary framework to examine the relationship between great apes and their environments and also the potential role of developmental bias. Using ten years of field observations of ape ranging and feeding behavior, we compared resource selection and habitat use among sympatric chimpanzees (Pan troglodytes troglodytes) and western lowland gorillas (Gorilla gorilla gorilla) in the Goualougo Triangle of northern Republic of Congo. Combined with botanical surveys of their home ranges, our results showed that apes modify their environments in ways that systematically influence selection pressures acting on current populations and their descendants. This comparative approach provides a means of identifying the “ecological legacies” that each ape species bequests future generations and which may facilitate scaffolding of technological skill acquisition. We also compared potential developmental biases among these apes to determine if some kinds of variation were more common than others and possibly play a role in driving evolutionary change. Reconsidering the influence of environment and forces generating behavioral variation provides a fresh perspective on a long-standing debate about factors influencing the emergence and maintenance of material culture among apes.