November 19, 2018

Cross-Cultural Variation in the Life History of Human Foraging Skill

Jeremy Koster, University of Cincinnati, Ohio

Humans are distinguished from other hominoids by several life history traits, including prolonged childhoods, relatively brief inter-birth intervals, and extend post-reproductive lifespans. To explain the evolution of these traits, anthropologists have hypothesized that the cognitive demands of hunting necessitate extensive learning, which promotes late maturation and inter-generational food sharing. In this analysis, my colleagues and I evaluate a key component of this conceptual model, namely that advanced hunting skill is particularly evident among middle-aged hunters. We compile data on subsistence hunting from 40 sites around the world in a sample that includes over 23,000 hunting records from approximately 1,800 individual hunters. We use multilevel modeling and a life history model to estimate the latent skill of hunters as a function of their age. On average, hunters reach their peak at approximately 31 years old. The peak is not pronounced, however, and there is cross-cultural variation in age-related skill that challenges earlier findings. These results accentuate the need for additional longitudinal data on foraging activities as a counterpoint to theoretical models of life history evolution.