Polygyny, western egalitarianism, and the relative status of women in society

It is commonly believed that women experience lower relative status in polygynous societies, whereas it is mathematically the case that the average woman benefits materially (and the average man suffers reproductively) from the polygynous institution of marriage. In 1999, Kanazawa and Still hypothesized that the apparent negative correlation between polygyny and women's status was spurious and can be explained by “Western egalitarianism,” which simultaneously decreases inequality among men and thereby polygyny (according to the female choice theory of marriage institution) and decreases inequality between the sexes, thereby elevating women's status. However, their hypothesis was never empirically tested. I put Kanazawa and Still's hypothesis to an empirical test. Analyses of three widely varied international measures of gender inequality show that polygyny was not associated with women's relative status in society net of Western egalitarianism. Robustness checks confirm that the results are not unique to a specific measure of Western egalitarianism. The international data leave very little doubt that women experience lower relative status in polygynous societies, not because they are polygynous, but because they are inegalitarian and citizens (both women and men) lack civil liberties.