In most Western cultures, men are considered serial monogamist, polygynous harem-builders. However, among the Pimbwe of Tanzania in East Africa, “Women who worked their way through two husbands had, on average, higher productive success [and] a greater number of surviving children than either the more sedately mating women, or than men regardless of wifetime total.” So concludes a study by Monique Borgerhoff Mulder of The University of California, Davis, in the summer issue of Human Nature.
Among the Pimbwe, the men and women marry without ritual, and divorce by separating. In their small villages, the sexes share pretty much equally the labors of hunting, fishing, farming, gathering, housekeeping and raising kids.
“We’re so wedded to the model that men will benefit from multiple marriages and women won’t, that women are victims of the game,” says Dr. Borgerhoff Mulder. “But what my data suggest is that the Pimbwe women are strategically choosing men, abandoning men and remarrying men as their economic situation goes up and down.” Apparently, the women’s polyandrous conduct offers them the evolutionary advantage of an expanded familial network of care providers for their children.