Intergenerational Transfers, Life Histories and the Evolution of Sociality

Ronald Lee, University of California, Berkeley
Carl Boe, University of California, Berkeley

For species that provide extensive parental care after birth, one potential advantage of living in social groups larger than the immediate family is that such groups may provide a form of life insurance for offspring who would otherwise die following the death of one or both parents. We use a stochastic micro-simulation to investigate whether varieties of a species living in larger kin based or mixed social groups have a selective advantage. We also investigate how different social contexts modify evolutionary forces in ways that lead to different life history outcomes. One intriguing finding is that sharing groups that provide life insurance thereby shape life history evolution in a way that undermines their ability to compete effectively with groups without insurance. These and other interactions of evolution, demography, and sociality are explored.