Misleading on Monogamy

Even the best science journalists routinely misrepresent human sexual evolution.

Titi monkeys are monogamous--a way of life found in just 9 percent of mammal species (supposedly). Credit...Peter Macdiarmid/Getty Images

Carl Zimmer is a highly respected science journalist, a regular columnist at The New York Times, Discover, and National Geographic, and the author of over a dozen widely read books—most, but not all, about some aspect of evolutionary theory. So when Mr. Zimmer writes about human sexual evolution, one expects him to get it right, so when he gets it wrong, his mistakes offer fascinating insights into just how difficult it can be—even for the most intellectually-gifted among us—to move beyond mainstream bias when discussing human sexuality.

For example, this article about the “problem of monogamy” in mammals offers striking examples of the omissions and cognitive contortions required to stick with the mainstream view when alternatives are just too emotionally threatening to face.

“Bonding” is not monogamy, so to conflate one with the other is both misleading and utterly unnecessary — unless you're striving to make monogamy seem more prevalent among primates than it actually is.

The first problem is apparent before the article even begins. The caption under the photo of Titi monkeys explains that they are "monogamous—a way of life found in just nine percent of mammal species." This is way off, three times the generally accepted prevalence of monogamy in mammals, which is about 3 percent. It could be even worse. According to the National Science Foundation, “Not a single mammal species has, thus far, been definitively shown to be truly monogamous. … Scientists now estimate that only about three to five percent of the approximately 4,000+ mammal species on Earth practice any form of monogamy.”

“Any form of monogamy” would include things like social monogamy (where you nest together but have sex with others), short term monogamy (where mating pairs stick together for one season, but hook up with someone else next year), serial monogamy (where you only sleep with your husband, but you’ve been married a dozen times), and so on.