Highly polygynous societies do not lock large proportions of men out of the marriage market

There is a widespread belief that polygyny prevents many men from marrying— because it skews the sex ratios of marriage markets—and therefore that polygyny causes crime and conflict. We use demographic modeling to show that even cross-culturally high rates of polygyny will not necessarily lock any men out of marriage. We also examine this question using census data from 30 countries in Africa and Asia, plus the historical United States. We find that men living in more polygynous communities actually marry at higher rates than men in less polygynous ones. This is partly explained by differences in sex ratios between these communities. However, this also has a sociological explanation: highly polygynous populations often have strong pro-marriage norms, which may override polygyny’s effect of skewing marriage market sex ratios. Our results challenge the mechanism that is frequently invoked to link polygyny with mass violence.