All day
The anthropological record indicates that approximately 85% of human societies were socially polygynous, meaning that social norms permitted men to take more than one wife. While most foraging and small scale horticultural societies were socially monogamous, the polygyny was rare due to ecological constraints. However, complex agriculture led to large absolute differences, and in such societies polygynous marriages are common. In last two millennia, social norms forbidding polygyny (“social monogamy”) has spread across Europe, and then across the globe, even though absolute wealth differences have increased. In Henrich et al (in review) we explore the hypothesis that the norms and institutions that compose the modern package of monogamous marriage have been favoured by cultural evolution because of their group-beneficial effects—promoting success in inter-group competition. Social monogamy suppresses intrasexual competition, and this reduces crime rates, including rape, murder and assault, as well as personal abuses. It also decreases the spousal age gap, total fertility, and gender inequality. In shifting male efforts from seeking wives to paternal investment, normative monogamy increases savings, child investment and economic productivity. By increasing the relatedness within households while decreasing the number of unrelated dyads, normative monogamy reduces intra-household conflict, leading to lower rates of child neglect, abuse, accidental death and homicide. We assemble supporting evidence from biology, economics, history, criminology, sociology, public health and anthropology.
At the workshop we plan bring together scholars from relevant disciplines to further explore this hypothesis. We are particularly interested in developing alternative hypotheses, and in data on the actual spread of social monogamy in the last two millennia.