Doctoral Dissertation Research: The Ontogeny of Complex Tool Use in Great Apes

Washington University, Saint Louis MO

Investigators

Abstract

One of the hallmarks of human evolution has been the creation and use of complex tools, but the specific mechanisms by which this behavioral adaptation developed are not fully understood. This doctoral dissertation project will investigate the roles of teaching and imitation, as well as sex differences in foraging tool use, in the development of tool skills in a wild chimpanzee population. Chimpanzees are our closest living relatives, and the study of their tool traditions provides unique insights into the evolutionary origins of human culture and technology. This project will also provide student field research and training opportunities and support great ape conservation efforts at the research site. The specific goals of this project are to differentiate the social learning mechanisms involved in chimpanzees' acquisition of complex tool skills, quantify the impact of variable social learning opportunity, and evaluate competing hypotheses for sex differences in tool skill acquisition. Chimpanzees of the Goualougo Triangle, Republic of Congo, exhibit some of the most complex tool behavior among nonhumans, and this will be the first study to investigate how they learn these skills. Direct observations using focal and all-occurrence sampling will be conducted and supplemented by remote video footage of chimpanzee tool use. Both cross-sectional and longitudinal approaches will be employed to document the ontogeny of tool skills. Insights from this study will refine models of the evolution of material culture in the hominin lineage. Specifically, results will help to resolve debates about how social learning influences intraspecific behavioral diversity, illuminate how complex tool traditions are maintained among wild apes over generations, and clarify the ontogenetic origins of sexual differentiation in tool-assisted foraging among chimpanzees.