“THE STANDARD narrative of heterosexual interaction,” our authors write, “boils down to prostitution: a woman exchanges her sexual services for access to resources” and protection. Monogamy, possessiveness, jealousy, warfare, women’s alleged lack of interest in sex, even rape—so many prominent evolutionary psychologists tell us—were genetically hardwired into us in the Pleistocene era before the invention of agriculture.

Ryan and Jethá call the methodology that informs this narrative, quoting Darwin, “judging from the social habits of man as he now exists,” or, as the author’s put it in their own funny way, “flinstonization”—projecting current human social relations (which are not “natural” but historically and socially constructed) into our distant past and then calling it “natural.”

Sex at Dawn is a refreshing and humorous look at human sexuality that aims to debunk the sexist and conservative presumptions that clutter up and interfere with a true understanding of the topic. The authors provide ample evidence that our prehistoric, foraging ancestors were what today might be called sexually “promiscuous,” and include plenty of recorded examples of societies  that were far more egalitarian and open toward sexuality than we are today. Far from monogamy being somehow natural, it appears to be something that only developed fairly late in  human history. “Agriculture,” they write, “has involved the domestication of the human being as much as of any plant or other animal.” With the rise of agriculture and the first class societies comes the beginning of the repression of sexuality, especially of women’s sexuality.

Yet no matter how much our society tries to repress it, our sexual urges manage in various strange ways to find expression. One of the more startling revelations in the book (for me, anyway) was that for centuries up until the 1920s doctors “routinely massaged” female patients to orgasm to relieve them of symptoms of “hysteria”—defined as, among other things, “anxiety, sleeplessness, irritability, nervousness,” and “erotic fantasy.” One late Nineteenth century study estimated that in 1873 these “treatments” constituted “the single largest market for therapeutic services.” This, at the  same time women were being presented as sexless beings.

Various pseudo-theories are debunked with gusto. Humans are “naturally monogamous” and women less sexual than men? How, then, to explain that women are biologically equipped to engage in sexual activity whether they are ovulating or not? Why are women “hardwired” to be able to enjoy sex “week in and week out” for non-reproductive purposes? “In those societies which have no double standard in sexual matters and in which a variety of liaisons are permitted,” wrote anthropologists Cleland Ford and Frank Beach more than fifty years ago (in a passage quoted in the book), “the women avail themselves as eagerly of their opportunity as do men.”

To the argument that humans are naturally selfish, the authors note that this flies in the face of “copious data,” some of which they cite, “demonstrating that human social organization was founded upon an impulse for sharing for many millennia.”

The theory that men are naturally concerned with a child’s paternity, and are genetically programmed to want to raise only “their” offspring, is refuted by the fact that in foraging societies there was no way to determine paternity, and in fact many such societies believed that a child could be the product of the semen of more than one man. The  Aché men of Paraguay, for example, “find themselves bound to one another by shared paternity for the children they’ve fathered together.” Among the Matis people, according to one anthropologist the authors’ cite, “[e]xtramarital sex is not only widely practiced and usually tolerated, in many respects, it also appears mandatory.”

It turns out that in these societies, sharing goods as well as sharing sexual pleasure was a means by which people bonded with each other and strengthened their mutual ties to each other. Such behavior was “community building” and “conflict reducing.” In these societies—which existed far longer than our world since the development of agriculture and the division of society into classes—children were reared collectively, and parental responsibilities were shared among the group.

“Thou hast not sense,” complained one Montagnais Indian to the seventeenth-century Jesuit missionary Paul Le Jeune. “You French people love only your own children; but we all love all the children of our tribe.” The book is a treasure trove of such examples. 

The sexual pain and confusion experienced by most of us in our society, the authors argue, is the result of the disconnection between our natural sexual inclinations and the social mores and restrictions placed on us by modern society. If this is true, then a lot of damage has been done by our “bizarre, centuries-long war against any hint of childhood sexuality,” which compares very unfavorable to our pre-class ancestors, where children were allowed to explore their sexuality freely and without punishment or embarrassment. 

By the end of it, if you continue to believe in the Flintstone version of human sexuality, it’s certainly not the authors’ fault.