Karla Dial at CitizenLink:

When it comes to marriage and family structure, there’s a good reason nearly every modern society has encouraged monogamy as the accepted norm: Because it’s good for society.

So says a new multidisciplinary study published in Philosophical Transactions of the Royal Society, the world’s longest-running scientific journal, established in 1665. Though polygamy has existed throughout history — and is still accepted in some pockets of the world — a team of authors working in the fields of anthropology, economics and psychology write that it doesn’t benefit children, women, individuals or cultures the way married monogamous relationships do.

... According to the study, monogamy yields four primary benefits:

1) It reduces crime. Numerous studies show that when they’re married, men are 35 percent less likely to commit crimes, and 50 percent less likely to commit violent crimes. The same cannot be said of polygamous cultures — or countries where men outnumber women. In China, for example, the overall crime rate doubled between 1988 and 2004 as the number of males outpaced that of females.

2) Monogamy leads to gender equality. In monogamous societies, women are generally considered equal partners in the relationship. But as the number of wives grows, the power of each in the relationship decreases.

3) Monogamy reduces household conflict. Research shows children raised in polygamous homes face far less household stability — and more conflict and violence — than those raised in monogamous relationships. As one author pointed out, “living in the same household with genetically unrelated adults [not counting adoption] is the single biggest risk factor for abuse, neglect and homicide of children.”

4) Monogamy improves children’s well-being through greater paternal investment. The more wives and children a man has, the less time he has available to spend with each of them. Even though men in modern polygamous societies tend to be wealthier, their children suffer from poorer nutrition and lower survival rates than those in monogamous households.