Is Monogamy Unnatural?

In the middle of a national debate on same sex marriage, today’s CNN op-ed piece claims that the entire concept of marriage may be completely unnecessary. According to Meghan Laslocky we need to “Face It: Monogamy is unnatural.”

Laslocky claims that fidelity within marriage is a faulty gauge for its success, since “biologically, we humans are animals. So it makes sense to look to the animal kingdom for clues as to what we are built for.” Since most mammals aren’t monogamous, why should we expect humans to be any different? “Many are quick to label a person who strays from his or her marriage or relationship as a ‘cheater,’ but it’s really not that simple. It’s time for our culture to wake up and smell the sex pheromones: monogamy is not natural for many, or probably even most, humans,” said Laslocky.

When a man or woman cheats on his or her spouse, it’s simply the result of the person’s “brain wiring.” It’s simply unrealistic to expect humans to behave differently, especially since we are living longer than we did 100 years ago. With the average age of marriage being 28 for men and 26 for women, Laslocky explains, “this means that a person is theoretically expected to have one sexual partner for about 50 years. This seems like a lot to expect of any human being — even the most honorable, ethical and moral.”

Her argument is just one among many claiming that our sexual ethics are more a result of being biologically hardwired animals rather than of being responsible moral agents. Laslocky would have us believe that we’ve evolved to be a little higher than the animals; God would have us know that we were made “a little lower than the angels.” (Ps. 8:5)

But in a way, she has a point. Monogamy is unnatural. If all we are as humans comes down to just being the highest form of mammals, then she’s right – moral faithfulness is a completely unrealistic expectation.

But here’s why I believe Laslocky’s argument doesn’t hold up: We’re not highly evolved animals. We’re the Creator’s image-bearers. And marriage isn’t a culturally outdated social institution that suits our nature. Marriage is a culturally transcending message that displays and communicates God’s nature (Eph. 5:22-33). That kind of human relationship, and the self-denying faithfulness it requires, is unnatural.

Laslocky is right when she says monogamy doesn’t reflect a natural world, but that’s only because marriage was made to reflect a supernatural Creator. When we make marriage suit our own sin natures, we miss Who it’s really about.

What do you think of her argument? Is monogamy unnatural? And if so, does someone’s propensity to cheat excuse him or her because of biology, or is that person still morally responsible?

Katie McCoy is the editor of and is pursuing a PhD in Systematic Theology at Southwestern Seminary. When she’s not reading for her classes (a rare occasion!), she loves hanging out with friends, eating sushi, learning new words and shopping with her mom. Connect with Katie on Facebook or Follow her Twitter!

2 thoughts on “Is Monogamy Unnatural?”

  1. Enjoyed reading your article on monogamy is unnatural, you have defended the biblical values emphasising the how we are supernatural in the creator”s image. As I was reading, one important thing struck my mind, upholding the values of marriage… does it exist apart from biblical world? yes! it exists. most of the society which is developed in its functions doesn”t approve of what Laslocky says, probably they would excommunicate her from the society at least the society that I belong to (Indian society). Its pity that she has been pushed to learn social values from animals which lacks common sense. God has already written the values in human heart, the only thing is they have to search the values with the help of the scripture since human heart has become calloused by the disobedient nature.

  2. Josef says:

    The reason Christians are monogamous is because of the influence of the Romans, who converted to Christianity but kept their pre-Christian marriage laws. Monogamy is not required in the Bible. It is allowed, and so is polygyny (one man and multiple wives). Adultery is defined as a man sleeping with another man’s wife or a woman cheating on her husband. For a man to have extramarital relations is not adultery, unless the other woman is also married or engaged. Many great Biblical figures were polygynous, and the Bible gives many rules regarding polygyny, for example that a man who takes a second wife must continue to provide for his first wife. The Bible also requires levirate marriage, in which a man whose brother dies childless must marry his brother’s widow, and their firstborn son will be his brother’s heir. Nowhere does it say that only a single man should do this. The idea of forbidding men from having multiple wives comes from Rome.