Stefany M. Gomez (Universidad de Los Andes and Universidad Sergio Arboleda)
A widely held view is that our hunter gatherer ancestors lived in closed worlds, their interactions, limited to just a small number of close family or lifelong associates. However, the extent of genetic differentiation (Wright’s FST) in populations which are likely to have had population structures and characteristics similar to our ancestors suggests that this idea is incorrect. Under idealized assumptions in which only random migration and small group size are affecting the degree of genetic differentiation among groups, we show that the observed FST values could, indeed, be produced by small and isolated populations. However, when we introduce empirically plausible deviations from the idealized assumptions -reproductive skew, population crashes, single propagule recolonization processes, linage-based group fission and non-random migration- that reflect human social structure and social processes during the Pleistocene, our simulations indicate that the observed FST values could not be produced by small and isolated populations but are consistent only with large and cosmopolitan ones.
Mentors: Samuel Bowles and Jon Wilkins
SFI Host: Ginger Richardson