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Time for Sex at Dawn!

FAQ about Sex at Dawn. Win a book!

In celebration of the publication of Sex at Dawn this week, I'll be running a series of FAQ that often come up when we're talking about the book, whether at cocktail parties or conferences. You can see the whole list at our website here. Also at our site, you'll see a form for contacting us. If you're interested in the issues we cover in the book, and have a nagging question you'd like to see us take a shot at answering, let us know. We'll be choosing the five most interesting questions to answer in future blog posts here. If we choose your question, we'll send you a free copy of Sex at Dawn. Looking forward to your questions and comments.

1. Why is long-term sexual monogamy so difficult for many couples?

Several factors conspire to make long-term sexual monogamy difficult for people. As a species, we’ve evolved to be sexually responsive to novelty. From a genetic point of view, the lure of new partners (known to scientists as the Coolidge effect) combined with less responsiveness to the familiar (the Westermarck effect) motivated our ancestors to risk leaving their small hunter/gatherer societies to join other groups, thus avoiding incest and bringing crucial genetic vigor to future generations.

Another problem is that most people in the West marry because they’re “in love,” which is a temporary, blissfully delusional state we should enjoy, but not expect to last forever. As the German poet, Goethe put it, “Love is an ideal thing, marriage a real thing. A confusion of the real with the ideal never goes unpunished.”

2. Why do you specify “sexual monogamy?” Isn’t all monogamy sexual?

Biologists distinguish sexual monogamy from social monogamy. As DNA testing has grown cheaper in recent years, we’ve learned that most species formerly classified as “monogamous” (primarily birds) are socially monogamous, but not sexually so. In other words, they form pairs that cooperatively care for that season’s brood of young, but the male may well not be the biological father. Applied to humans, we argue that a more flexible approach to sexual fidelity can increase marital stability and thus lead to greater social and family stability.

3. How can you say that humans are the most sexual species? This makes us sound like animals.

Actually, most animals would consider us the sex maniacs. Almost all animals have sex only for reproduction—just when the female is ovulating. But humans (and our closely related cousins, the bonobos) have sex for an endless list of reasons. We do it for fun, for pleasure, for money, to cement a friendship, for ego gratification, to relax, to seal a business deal or political alliance (think of arranged royal marriages), and yes, sometimes even to make babies. If you consider the ratio of copulations per birth, humans and bonobos are off the charts. Then, if you add all the hours spent fantasizing, remembering, planning, masturbating, porn and soap-opera watching, romance novel reading . . . .

4. Even if you’re right that humans aren’t “naturally” monogamous, we’re conscious beings with free will to decide how we live, so what’s wrong with simply choosing to be monogamous?

Nothing, as long as we fully understand and accept the costs involved in choosing behavior that conflicts with how we evolved. For example, you might happily choose to work the night shift, but the resulting disruption of your circadian clock will increase your risk of cancer, cardio-vascular disease, gastric disorders, and so on no matter how committed you are to your decision. Similarly, we can choose to wear tight corsets, or ill-fitting shoes, or to live on chili-dogs and ice cream, but because all these behaviors run counter to our evolved nature they will cost us over time. Like celibacy, lifelong sexual monogamy is something we can certainly choose, but it should be an informed decision.

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