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Most people in the USA identify marriage as a natural goal for humans, with love as a necessary component. After all, Frank Sinatra sang “love and marriage, love and marriage, go together like a horse and carriage” and informed us that “you can’t have one without the other.”
With all of the debate and discussion about same-sex marriage in the past few days, it is worth busting a few myths about “happily ever after.” It is not human nature to seek marriage and a specific romantic relationship, but it is our nature to pair bond and it is our culture to seek marriage.
At this juncture, it’s critical to mention that the current view of marriage that dominates the Judeo-Christian religions and the cultures that are intertwined with them (like ours), is a fairly recent occurrence in human history. The idea that romantic love and marriage are connected and that marriage is the ultimate outcome for a couple in love gained prominence in the 16th century and rapidly spread across much of the western world, and now much of the globe. Previously, and in many societies still today, there is no necessary connection between romantic love and marriage.
However, when most people think about marriage, they think about “love” being at its base, and are really asking about the “the romantic pair.” To figure out a basis for romantic love we need to explain the particular strong relationship between two people we call the pair bond. Unfortunately, in our society we often confuse “pair bond” with “marriage.” They are not the same thing.
In a biological sense there are two types of pair bonds: the social pair bond and the sexual pair bond. The social pair bond is a strong behavioral and psychological relationship between two individuals that is measurably different in physiological and emotional terms from general friendships or other acquaintance relationships. The sexual pair bond is a behavioral and physiological bond between two individuals with a strong sexual attraction component. In this bond the participants in the sexual pair bond prefer to have sex with each other over other options. In humans, and other mammals, pair bonds are developed via social interactions combined with the biological activity of neurotransmitters and hormones such as oxytocin, vasopressin, dopamine, corticosterone, and others.
Pair bonds, both social and sexual, in humans are part of complex social networks that emerged as central patterns in human evolution. Pair bonds can involve sexual relationships (and in a cultural sense, romantic attachments) and are probably involved in what most people experience when they think of romantic love. We have extensive social pair bonding across genders and age categories, probably more than any other species. We can have social pair bonds with our relatives and our closest friends. They can be with same-sex individuals or different sex individuals, same-age or different ages. Humans also have sexual pair bonds both heterosexually and homosexually. Importantly, our sexual pair bonding, like our sexual activity, is not limited to reproduction.
However, pair bonds ≠ marriage.
There is an extensive body of research looking into the history and structure of marriage systems throughout the world, too voluminous to review here. Basically, social scientists and historians agree that marriage (in both secular and religious systems) is best viewed as a social system for legitimizing reproduction and inheritance of property, control of and regulation of sexual activity, and, recently, the culturally sanctioned outcome of romantic “love.”
Marriage is also an important way in which cultures officially recognize and sanction the sexual pair bonds that characterize human beings. Remember, human sexual pair bonds naturally occur both heterosexually and homosexually. However, in many societies, social and political histories have created contexts where heterosexual pair bonds are sanctioned and homosexual pair bonds are not.
We know that social and sexual pair bonds are an important part of being human, and in many cases we expect these bonds to be associated with marriage or some other form of culturally sanctioned relationship. But are all married couples sexually pair bonded and/or socially pair-bonded? Given the enormous variation in why and how people marry, probably not. But there is very, very little research asking these questions. We currently have no data on this critical measure.
While the variably defined cultural concepts of “marriage” are not part of human nature, pair bonds most assuredly are. Scientifically we know that pair bonds occur both heterosexually and homosexually. But, unfortunately, in some cases this is a scenario where science and cultural perceptions do not agree.
The recent conversation about same-sex marriage and the acknowledgment of the rights of people who have pair bonds to have those bonds culturally recognized is a positive one. Maybe this shift indicates that our cultural perceptions are finally beginning to catch up with what we know, biologically, about human pair bonding and sexual behavior.
Some good books on this topic:
- Barash, D.P. and Lipton, J.E. (2001) The myth of monogamy.
- Ellison, P.T. and Gray, P.B. Eds.(2009) The endocrinology of social relationships. Harvard University Press Pp. 270-293
- Fuentes, A. (2012) Race, monogamy and other lies they told you: busting myths about human nature. University of California Press
- Squire, S. (2008) I don’t: a contrarian history of marriage. Bloomsbury Press.
