According to Christopher Ryan and Cacilda Jethá, the authors of the new book “Sex at Dawn: The Prehistoric Origins of Modern Sexuality,” the state of the American marriage is awfully grim. We have a stratospheric divorce rate and a surge of single parents. Couples who stay together are often trapped in sexless, passionless unions. An entire industry — from couples therapy to sex supplements — has emerged to help people “rekindle the spark” without straying from the confines of monogamy.
But Ryan and Jethá also have a theory for what’s causing this misery: From a biological perspective, men and women simply aren’t meant to be in lifelong monogamous unions. In “Sex at Dawn,” which uses evidence gathered from human physiology, archaeology, primate biology and anthropological studies of pre-agricultural tribes from around the world, they argue that monogamy and the nuclear family are more recent inventions than most of us would expect — and far less natural than we’ve come to believe.
Before the advent of agriculture, they argue, prehistoric humans lived in a much less sexually possessive culture, without the kind of lifelong coupling that currently exists in most countries. They also point to the bonobos, our closest relatives, who live in egalitarian and peaceful groups and have astronomical rates of sexual interaction, as evidence of our natural inclinations. While Ryan and Jethá’s book (Ryan is a psychologist, and Jethá a practicing psychiatrist, in Spain) is often a bit scattered and hard to follow, its provocative argument is also impossible to dismiss.
Salon spoke to Ryan over the phone from Barcelona about the problem with American marriages, why gay men understand relationships better than straight men, and the hidden meaning of human testicle size.