Got the Urge to Cheat? Don’t Worry, It’s Only Natural

We were a couple of married ladies, passing the time with idle conversation about old boyfriends.

“Have you ever thought lustfully about other men?” I asked my friend. “I mean, have you ever thought about having sex with other guys?”

“Oh sure,” she said. “Who hasn’t?”

“But would you ever do it?”

“No, of course not,” she said. “I love my husband.”

“Yeah,” I said, “me too, but that doesn’t mean you don’t get the urge.”

“That’s true,” she replied. “I think most people would love to have sex with someone besides their spouse. As long as there were no repercussions.”

Ah, yes, repercussions.

Those little details: devastation, disease and divorce. Ah, well. We agreed that repercussionless extramarital sex was a universal fantasy--for both sexes--then segued into our next favorite topic: what our husbands had done lately to make us want to rip out their nose hairs.

But afterward I found myself brooding: Could that really be true? How can we be programmed for infidelity when society places such a premium on monogamy? Are our “urges” rooted in biology and therefore impossible to ignore?

Last week, when I saw the cover of Time--with a golden wedding band snapped in half and the provocative headline, “Infidelity: It may be in our genes”--I remembered our chat.

Turns out that with her own simple logic, my friend had demonstrated an unschooled appreciation for the burgeoning field of evolutionary psychology.

*

The article in Time is a much-condensed version of a book called “The Moral Animal: Evolutionary Psychology and Everyday Life” by New Republic Senior Editor Robert Wright. It is one of a number of recent books that attempt to view human reproductive behavior through the lens of evolution, to explain our messed up sex lives in the context of Darwinian survival.

Wright pulls together research that ranges over the bumpy terrain of love, looking for biological cues to our behavior, attempting to answer timeless questions such as why wealthy men take trophy wives, why most societies throughout history have been polygamous and why we cheat.

The answer to all these questions, evolution-wise, is propagation of the species.

“The good news is that human beings are designed to fall in love,” Wright says. “The bad news is they aren’t designed to stay there. According to evolutionary biology, it is ‘natural’ for both men and women . . . to commit adultery or to sour on a mate, to suddenly find a spouse unattractive, irritating, wholly unreasonable. . . . It is similarly natural to find some attractive colleague superior on all counts to the sorry wreck of a spouse you’re saddled with.”

(Act on your impulses, though, and that attractive colleague could one day be that sorry wreck of a spouse.)

Conventional wisdom--as it’s often expressed on talk shows and in magazines--holds that men are programmed to stray while women are programmed to stay.

Not so, Wright says.

“Women are not by nature paragons of fidelity,” he says. “Wanderlust is an innate part of their nature, ready to surface under propitious circumstances.” But, he adds, “If you think women are bad, you should see men.”

(On behalf of my gender, I thank him for that.)

*

So why are we inclined to stray?

Evolutionarily speaking, women’s innate wanderlust is geared toward confusing the paternity of a child--on the theory that a man who thinks he may be the father will be disposed to offer care and protection. The more men who think they could be the father, the more protectors a child will have.

Men want to jump into bed with everything that moves for an entirely different reason: The more sex they have with young, healthy females, the more likely they are to produce healthy offspring, thus ensuring the bloodline. (Added evolutionary bonus: each time a male impregnates a female, she is less likely to pass on the genes of another male.)

Now. The next time you see a luscious prospect and reach instinctively to remove your wedding band, remember: You are normal and you do not have to act on your lust.

Your positive sexual response to another person does not mean you married the wrong guy or gal, Wright says.

It simply means you are human.

And so--don’t forget--is the person you married.