Many such examples suggest that the mating system is constrained by the way species are socially adapted to their food supply. ... The consequence of man's economic dependence takes different forms in different societies, but recall that according to Jane Collier and Michelle Rosaldo, his needing a wife to provide food is universal among hunter-gatherers. Food, it seems, routinely drives a man's marriage decision more than the need for a sexual partner.

Among the Inuit, where a woman contributed no food calories, her cooking and production of warm, dry hunting clothes were vital: a man cannot both hunt and cook. The pressure could drive widowers or bachelors to neighboring territories in an attempt to steal a woman, even if it meant killing her husband. The problem was so pervasive that ... unfamiliar men would normally be killed even before questions were asked. Lust was not the motivation for stealing wives. "The vital importance of a wife to perform domestic services provided the most usual motive for abduction," according to ethnographer David Riches.