Oh dear, here we go again, everyone yelling the world will end if gays marry and bring up children. The fundamental error common to so-called “protectors” of traditional marriage lies in assuming that marriage has a fixed form and any tinkering will cause it to implode.
Look at the statement released a couple of months ago by the American Anthropological Association, which said, in part, “The results of more than a century of anthropological research on households, kinship relationships and families, across cultures and through time, provide no support whatever for the view that either civilization or viable social orders depend upon marriages as an exclusively heterosexual institution.” In other words, relax: the sky isn’t about to fall.
The AAA went on to say “Rather, anthropological research supports the conclusion that a vast array of family types, including families built upon same-sex partnerships, can contribute to stable and humane societies.”
Detractors somehow reach the conclusion that because the rate of decline of so-called “traditional marriages” appears to have increased in Sweden since the introduction of same-sex marriage, that the two pehonomena are causally linked. There's no evidence to show that there is, in fact, any connection; the decline was already taking place and the rate has remained unchanged.
This so-called “traditional” marriage is in fact a relatively recent invention: according to anthropologist Roger Lancaster (The Trouble With Nature: Sex & Science in Popular Culture) it didn’t exist in Old Testament pre-Christian times, and took hundreds of years to become the norm as Christianity spread. Until then most marriages were polygamous, and everyone seems to have managed quite nicely.
Marriage for love, or for the care of children – rather than marriage as a property transaction and children as cheap agricultural labour – has only been the accepted definition for around 200 years. The heterosexual nuclear family, rather than the multi-generation model, only came into being during the Industrial revolution, as families became more mobile in the search for work and extended families ceased to remain on one patch of ground for life.