According to Henrich, monogamy's main cultural evolutionary advantage over polygyny is the more egalitarian distribution of women, which reduces male competition and social problems. By shifting male efforts from seeking wives to paternal investment, institutionalized monogamy increases long-term planning, economic productivity, savings and child investment, the study finds. Monogamy's institutionalization has been assisted by its incorporation by religions, such as Christianity.
Monogamous marriage also results in significant improvements in child welfare, including lower rates of child neglect, abuse, accidental death, homicide and intra-household conflict, the study finds. These benefits result from greater levels of parental investment, smaller households and increased direct "blood relatedness" in monogamous family households, says Henrich, who served as an expert witness for British Columbia's Supreme Court case involving the polygamous community of Bountiful, B.C.
Monogamous marriage has largely preceded democracy and voting rights for women in the nations where it has been institutionalized, says Henrich, the Canadian Research Chair in Culture, Cognition and Evolution in UBC's Depts. of Psychology and Economics. By decreasing competition for younger and younger brides, monogamous marriage increases the age of first marriage for females, decreases the spousal age gap and elevates female influence in household decisions which decreases total fertility and increases gender equality.
|Contact: Basil Waugh|
University of British Columbia