By Richard Feinberg

After years of argument a half-dozen states and the District of Columbia have legalized same-sex marriage. Several more, including my own, are considering it. Meanwhile, Republican presidential candidates, right-wing columnists and talk show hosts, evangelical pastors, and recently even Pope Benedict have called upon Americans to halt the spread of "immorality." Family values, we are told, require us to defend marriage as "traditionally defined." As an anthropologist I find this whole discussion rather odd.

Generations of my colleagues have agreed that marriage is a cross-cultural universal. Every known community, with one or two arguable exceptions, has had some marriage system. Common American assumptions about marriage, however, do not apply to large numbers of "traditional" communities.

Despite the claim that marriage is a bond between one man and one woman, polygamy (defined broadly as plural marriage) is extremely common and was even more so in the past. The most frequently encountered variant is polygyny, the marriage of one husband to multiple wives. Often, the co-wives are sisters, an arrangement known as sororal polygyny. Less common variants are polyandry (one wife, multiple husbands) and polygynandry (an arrangement that involves multiple spouses of both sexes). We even have reports from East Africa's Nuer of "ghost marriage," where a man marries a woman in the name of his deceased brother. The dead brother is regarded as the woman's husband, and her children consider his ghost to be their father. They call the man who is cohabiting with their mother by a term that normally means "uncle."

Among the world's known cultures, most have accepted polygyny as legitimate. Many have actively preferred it. It is far from some quaint, exotic practice; indeed, it is well-established in the Bible. Ironically, however, even in communities that permit polygyny, people typically marry monogamously, not for moral reasons but for economic ones. Few men have the resources to support more than one wife and her children.

While people usually content themselves with just one spouse, monogamy has many variants. In the Roman Catholic tradition marriage is for life, and divorce is forbidden. Similarly, Polynesians of Anuta, a Pacific island I have studied now for close to 40 years, are affiliated with the Church of England and do not permit divorce. The fact that marriages are durable, however, does not mean they are always happy.

In most places divorce is possible, and it is often followed by remarriage. The result, known technically as serial monogamy, is familiar to Americans -- as it is to many other peoples.

In much of the modern world, marriages are initiated by the couple on the basis of personal attraction. In a substantial number of communities, however, marriage partners are selected by the parents of the bride and groom. Sometimes the transaction is completed while the couple are still children. This makes sense in light of the anthropological finding that marriage is often a political and economic arrangement between groups rather than a personal arrangement between individuals. Such marriages are structured differently from ours, yet they are just as likely to be happy and long-lasting.

Seen in an anthropological light, gay marriage is one variant in a remarkably diverse set of practices. Same-sex marriages are not exactly commonplace in the mosaic of world cultures. Neither are they absent from "traditional" societies, however, despite the claims of those who argue for a legal ban on same-sex marriages.

Non-marital but regularized homosexual contact is well-known in certain regions of New Guinea, where boys are required to undergo ritualized homoerotic experiences as they grow into manhood. Same-sex marriage, more properly speaking, is reported from some parts of western Egypt. The Nuer, mentioned above, sometimes reclassify a barren woman as an honorary man. She then takes a wife and selects a suitable man to produce offspring on her behalf. Perhaps the best-known illustration of same-sex marriage, however, is the berdache, a character found among many American Indian tribes.

In most parts of Native North America, people made allowances for boys who wished to eschew stereotypical male sex roles. They dressed in girls' clothes, kept company with girls while growing up, took on women's roles around the camp or village, and upon reaching adulthood might take a husband. The berdache was a respected member of the community and was often thought to have extraordinary spiritual powers.

Anthropologists have found that all these arrangements "work" in the sense that people in communities that practice them are able to live happy, active, rewarding lives. So should they be encouraged in the 21st-century United States? Here, a bit of scholarly equivocation is called for. Each arrangement has both costs and benefits, and what works in one community may not perform as well in others.

However, to assess the value of such practices requires that we know what has been tried and how the salient customs have affected people's lives. To reject a type of marital arrangement because of its supposed incompatibility with "the traditional definition of marriage" only calls attention to the speaker's ignorance of well-known ethnographic and historic facts.

Richard Feinberg is a professor of anthropology at Kent State University, where he has taught since 1974. He earned his M.A. and Ph.D. at the University of Chicago and has conducted research with the Navajo in New Mexico as well as Polynesians in the Solomon Islands and Papua New Guinea. Feinberg has published over a dozen books and monographs, and approximately 100 professional articles. He has served as chair of the Association for Social Anthropology in Oceania, president of the Central States Anthropological Society, and Chair of Kent State's Faculty Senate.