1Department of Human Evolutionary Biology, Harvard University, 2Department of Biology, McGill University, 3Behavioural Biology Group, Department of Biology and Helmholtz Institute, Utrecht University
Thursday 11:15-11:30, Galleria South
Culture has played a major role in human evolution, and behavior patterns implicated in cultural development, such as innovation, extractive foraging, and social learning are observed in diverse animal species. Understanding the costs of these underpinnings of culture is necessary to understand how and why culture emerges along some lineages but not others. One such cost is infectious disease. Specifically, higher frequency of innovation or extractive foraging may be associated with greater environmental transmission of parasites, while higher frequency of social learning may be associated with greater social contact and, thus, more socially transmitted diseases.
We investigated these links using phylogenetic comparative methods, controlling for sampling effort, body mass, group size, and geographic range size. We predicted positive associations between parasite species richness and observed frequencies of innovation, extractive foraging, and social learning. Among 127 primate species, we found a positive association between total parasite richness and total observations of the three studied behavior patterns recorded for each host species. This relationship was driven by two independent phenomena: contagious diseases were positively associated with rates of social learning, and environmentally-transmitted diseases were positively associated with rates of innovation and extractive foraging. We found evidence for moderate phylogenetic signal in the statistical models.
Based on these findings, we propose that parasites are a potential cost of behavioral patterns vital to the evolution of culture. Our study calls for further investigation into infectious disease and other ecological factors as constraints on the evolution of culture in humans and other animals.
This study was funded in part by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144152, Utrecht University’s High Potentials Programme, and the Netherlands Organisation for Scientific Research (NWO) Evolution and Behaviour Programme; training in phylogenetic comparative methods was provided by the AnthroTree Workshop, which is supported by the NSF (BCS-0923791) and the National Evolutionary Synthesis Center (NSF grant EF-0905606).