High-performance agent-based models of worldwide human dispersals
Channel: Recording Archaeology
Date: 2015-06-12

Abstract: Recent advances in palaeoanthropology, archaeology, and ancient genomics, have yielded unprecedented insights into the prehistory of Homo sapiens. Worldwide spatial patterns of genetic and phenetic distance and variation, as well as archaeological findings, can be interpreted in the context of an African origin and out-of-Africa dispersal of our species during the late Pleistocene. However, quantitative tests of hypotheses about the population dynamics of the genus Homo are difficult to conduct, since models of large-scale human dispersals often neglect intrinsic stochasticity and environmental variability, and genetic patterns are modeled in terms of local populations or demes. Here we present an agent-based modeling framework for large-scale population dynamics that is able to handle millions of agents and timesteps in a geographically and ecologically structured environment. We show results from simulations of the out-of-Africa dispersal of Homo sapiens in which each agent can be thought of as a simplified, single individual. From these, we reconstruct the worldwide genetic history of our simulated populations, tracing back the complete ancestry of sample individuals. Finally, we show how large-scale parameters of population demography and diffusion affect the emerging spatiotemporal patterns and genetic signatures of the dispersal process.


Authors: Simone Callegari, John David Weissmann, George Lake, Christoph P. E. Zollikofer