Most societies that allow plural marriage prefer polygyny
Polygamy means being married to more than one spouse at once. A man with several wives practises polygyny, and a woman with several husbands practises polyandry. Societies variously encourage, tolerate, or outlaw the custom, and wherever it is allowed, polygyny is by far the more common form.
The Ethnographic Atlas tallied 1,231 societies recorded between 1960 and 1980: 588 with frequent polygyny, 453 with occasional polygyny, 186 monogamous, and just 4 polyandrous, though later research found some polyandry in 53 communities. The practice clusters in a polygamy belt across West and Central Africa; Pew puts it at 36% in Burkina Faso, 34% in Mali, and 28% in Nigeria, and 11% of sub-Saharan Africans lived in such unions as of 2019.
Scholars disagree about causes. Jack Goody linked it to shifting horticulture in which women do much of the farm work, yet also argued that the motives are sexual and reproductive rather than economic. James Fenske’s 2012 analysis tied rates instead to child mortality and ecological shocks, and some researchers point to the slave trade’s distortion of sex ratios in Africa.
Co-wives may be sisters, known as sororal polygyny, or unrelated. Senior wives sometimes help raise the bride price for another wife, since a junior wife lightens their work and can lift the household’s standing. Levirate marriage, in which a brother weds a widow, and the sororate, in which a widower marries his late wife’s sister, can both yield multiple wives. Imperial China accepted concubinage until the Qing dynasty. Polyandry is far rarer but is written into Gabon’s legal code, and India recognizes polygamous marriages only for Muslims.
Anthropologists describe humans as mildly polygynous. Genetic evidence suggests prehistoric men with living descendants fathered children with between 1.5 and 3.3 women on average, and that monogamy spread within the last 5,000 to 10,000 years alongside agriculture, private landholding, and inheritance.
Source: Polygamy
