Every society has certain socially prescribed rules that regulate mating and marriage, yet those rules can vary substantially. Understanding how cultural traditions differ can help us understand behavioral differences between societies. Polygyny—one male married to more than one female—is a practice with large differences across cultures: in some societies, nearly all marriages are polygynous ones, while in others the practice is banned entirely. One question that has plagued anthropologists for decades is: how much can the practice of polygyny be explained by female choice and how much can be attributed to male coercion and male dominated social traditions?

In a recent article for this magazine, Jerry Barnett argues that,

Although traditional polygamy is often presented as the exercise of male power, this is inaccurate. Polygamy results from female choice. In pre-civilized societies, unrestrained by social pressure to leave attached men alone, women would select the best available mate, whether or not he already had other mates. This resulted in the imbalances mentioned earlier, and in the creation of a rigid class system that divided men into a minority of breeders and a majority of losers. This system broadly serves the needs of women, and of the winning male minority. It also serves the wider community, by selecting the best male genes in each generation, and so accelerating human evolution.

As we can see, Barnett appears to consider polygyny to be entirely the result of female choice. Is that the case?

Attributing definitive, single causes to complex human behaviors is always a fraught endeavor. Nonetheless, by examining the types of social traditions that societies with high rates of polygyny tend to have, we can consider whether the weight of evidence supports this female choice explanation.

In his 2003 paper, “The Mating System of Foragers in the Standard Cross-Cultural Sample,” anthropologist Frank Marlowe found that there are more polygynously married women in hunter-gatherer societies where female marriage is arranged. This pattern also holds for societies with other subsistence systems. Marlowe writes:

Among all 186 societies in the SCCS [Standard Cross-Cultural Sample], there is greater polygyny where female marriages are arranged but not where male marriages are arranged, suggesting that marriage arrangement is a form of male coercion and a way parents can benefit by supplying the most influential males with brides.

Similarly, anthropologist John Hartung found that, across the hundreds of societies coded in the Ethnographic Atlas, greater polygyny is associated with the practice of bride price (in which a potential groom or his family provides goods or wealth to the potential wife’s family) and a greater male bias in terms of inheritance of goods and property. These practices also tend to mean a younger age at first marriage for girls, who are often betrothed while still children—usually to much older men. This is a consequence of the bride price, which leads to young daughters being married off in exchange for wealth or goods such as livestock, so wives can eventually be purchased for the sons. Anthropologist Lucy Mair writes that among pastoralist societies with high rates of polygyny,

Where cattle payments are made, the marriage of girls tends to be early for the same reason that that of men is late—that a girl’s marriage increases her father’s herd while that of a young man diminishes it. Of the Luhya, Wagner notes that the impatience of sons to marry and the reluctance of daughters to lose their freedom are both causes of family dissension.

Broadly, the cross-cultural pattern described above seems to support the idea that polygynous marriage is often the result of wealthy and/or influential families trading for or purchasing wives for their sons or other male kin, and not due to female choice.

For a more specific example, we can consider the marriage practices of the Tiwi hunter-gatherers of North Australia. The Tiwi—like many other aboriginal Australian societies—had a system that has sometimes been referred to as gerontocratic polygyny, in which most women were polygynously married to old men, while most young men remained single. The Tiwi also practiced infant bestowal and widow remarriage: young girls would be promised in marriage by their fathers before they were even born, while widows were required to remarry soon after the deaths of their husbands. Anthropologists Charles Hart and Arnold Piling write that:

the twin mechanisms of infant bestowal and widow marriage resulted in a very unusual type of household, in which old successful men had twenty wives each, while men under thirty had no wives at all and men under forty were married mostly to elderly crones.

The Tiwi social system also illustrates the important role ecology and subsistence patterns play in promoting or constraining polygynous marriages. Hart and Piling add that,

The most concrete symbol of Tiwi success was the possession of surplus food, for this not only permitted its possessor to make gifts to others and throw large parties for which he picked up the check, but also gave him lots of leisure time to devote to social and political life. Since a man required a large number of women in his work force if he was to build up a surplus of food, in the final analysis it was control of women that was the most tangible index of power and influence. Women were the main currency of the influence struggle, the main “trumps” in the endless bridge game.

Polygynous marriages across cultures are more common where males contribute less to subsistence. When most of the food is procured by females, males tend to spend less time with their children and more time devoted to pursuing mates or engaging in warfare. Where males contribute more on average to subsistence, it is more difficult for them to generate the amount of food necessary to support multiple wives, and this inhibits higher rates of polygyny. The relative rarity of polygyny among the Copper Inuit, who were almost wholly reliant on male hunting for subsistence, provides a good example of this pattern. Anthropologist Diamond Jenness writes that,

Very few men have more than one wife each. Polygamy increases their responsibilities and the labour required of them; moreover it subjects them to a great deal of jealousy and ill-feeling, especially on the part of men who cannot find wives for themselves. The Eskimo polygamist, therefore, must be a man of great energy and skill in hunting, bold and unscrupulous, always ready to assert himself and to uphold his position by an appeal to force.

Jenness emphasizes that, to take and keep multiple wives, a Copper man must be a skilled and hard-working hunter, able to manage the jealousy of co-wives, as well as that of rival men, and defend his wives by force when necessary. Jenness notes an example of a man named Norak who took another man’s second wife by force:

Norak, being unable to obtain a wife elsewhere, laid hands on Anengnak’s second wife one day and began to drag her away. Anengnak caught hold of her on the other side, and a tug of war ensued, but finally Norak, though the smaller of the two, succeeded in dragging her away to his hut and made her his wife.

One relatively common pattern is for secondary wives to be valued for their labor. Jenness notes that one man told him that he took his second wife to help with dressing and packing the meat he brought back to camp. Consider another example of polygyny among the Arapesh horticulturalists of New Guinea. Anthropologist Donald Tuzin tells the story of a woman who was in polygynous marriages twice:

Akwaliwa recalled that her first marriage had been to Kunai, who was now charitably, but discreetly (so as not to arouse gossip), helping to support her in widowhood. Because Falipa’w (Kunai’s senior wife) and one or two of the other cowives did not like her, the original union soon dissolved, and Akwaliwa took up with Asao as his second wife. Not long afterward, the first wife died. The two lived monogamously for three or four years before Asao casually asked what she would think of his taking another wife. Akwaliwa, angry and jealous at the question and still bruised by the troubles she had had as a cowife, refused to hear of it. Asao quickly dropped the subject. Afterward, however, touched that Asao so clearly respected her feelings, Akwaliwa inwardly relented. Accordingly, when Asao next raised the question—saying gently that she would have someone to help her in the gardens and grooves, someone to keep her company during his frequent prolonged absences—Akwaliwa gave her consent. A second wife joined the household soon afterward. After some initial difficulty, which Asao skillfully resolved, the two women got along very well together, and in due course a third was smoothly added to the household. “We all lived very happily together,” said Akwaliwa.

This illustrates some of the complexities of polygynous marriage: female labor as a motivating factor, jealousy and conflict between co-wives, and even the initial preference for monogamous marriage, although this does seem to be an example of a successful and largely voluntary polygynous marriage. It’s important to keep in mind, though, that the Arapesh also practiced bride price, arranged marriages by kin, and had a ‘men’s cult,’ which dominated society and exerted strong control over the women, so we should not assume these outcomes were entirely due to choice.

Conflict between co-wives is relatively common across polygynous societies. As a consequence, co-wives do not always reside in the same household, and instead each mother and her children may require their own home. In his 1949 work Social Structure, anthropologist George Murdock writes:

The polygynous family creates problems of personal adjustments which do not arise under monogamy, notably disputes arising from sexual jealousy and over the distribution of economic tasks in the feminine sphere of activity. A number of cultural solutions are apparent in the data. We have already noted the frequency with which co-wives are assigned to separate dwellings. Another common solution is to give one wife, usually the one first married, a superior social status and to delegate to her a general supervisory authority over the feminine tasks of the household.

A relatively common—though not universal—pattern found in societies with polygyny is that monogamously married women and first wives tend to have better outcomes for themselves and their children than second and third wives. Anthropologist Caroline Uggla and her colleagues found that among the Arsi Oromo agropastoralists of Ethiopia, “Results show that there are no significant differences in child survival between monogamous women and first wives, but second order wives or higher have 23–24% lower odds of survival for sons and daughters than monogamous women.” Anthropologist Beverly Strassmann found higher rates of child mortality among even first wives compared to monogamously married women among the Dogon pastoralists of Mali.

At the same time, co-wives are also sometimes considered a source of support. Among the Himba pastoralists of Nimibia, a majority of women surveyed supported polygyny. Anthropologist Brooke Scelza notes that, “Himba women listed a variety of benefits to having co-wives, including help with domestic tasks, including caring for livestock (mainly milking cows, which is made much easier with at least two people), working in the garden, caring for children, making repairs to the compound, and fetching wood and water.” However, about half of the Himba women surveyed said sexual jealousy was a problem, and 44% listed conflict over resources as a problem. In addition, first marriages are often arranged for young Himba girls through bride price, and the Himba live patrilocally (in the husband’s natal village), so the main role of female choice in such scenarios is not necessarily in the choice of partner, but in the freedom to divorce and return to their own natal homes if the marriage doesn’t work out. Scelza writes that,

Overall, social factors such as the ability to divorce and return to one’s natal home between marriages mean that Himba women have a large degree of choice in relation to polygyny, with those who are in positive relationships often choosing to stay and those who are unhappy able to leave. This likely accounts for the generally positive perception of the practice among Himba women.

Much of the Himba data indicates that having assistance with domestic tasks is a significant driver of perceptions of polygyny. Women who have elder daughters, or other adult female kin in their household, tend to have more negative views of polygyny, while those without that degree of social support and assistance in tasks tend to have a more positive view of the practice.

In his 2017 book The Psychology of Marriage, psychologist Glenn Weisfeld and his colleagues note that, “Pair bonding is an evolved tendency [in humans] with genetic, hormonal, and societal supports, and defense of the pair bond through jealousy and mate guarding.” And further that, “Traits that enhance mate value, success in remaining married, and success in raising children have been selected for,” in humans. As I previously discussed in an article on monogamy for Quillette, my impression from the ethnographic record is that most people (male or female) in most, if not all, societies generally prefer not to have to share their partner. When there are lower rates of polygyny in societies in which people have greater freedom to choose their partners, female choice probably does play some role in the polygynous unions we see. Further, female choice is exercised through divorce or through attempting to prevent a husband from adding another wife. However, where you see the extreme rates of polygyny, such as among the Tiwi, this usually seems to be the result of social institutions that promote arranged marriages, in which wealthier, older, higher status males receive multiple young wives in exchange for goods or wealth.

It is the practice of widespread polygyny, not monogamy, that tends to require more coercive social norms and institutions to maintain it. For most people in most societies, monogamy is usually the most widespread, and even preferred, form of marriage. Certain ecological circumstances may help promote or inhibit the practice of polygyny, but strongly male-biased cultural traditions are usually required to maintain it at high rates. In contemporary Western societies, where there is often a strong ethos of individual freedom, and where kin tend to have relatively limited involvement in marriage decisions, it is perhaps unsurprising that monogamy is the most widespread form of marriage and polygyny remains quite rare.