Female Orgasm as Mate Screening

Whereas Robinson suggests the evolutionary underpinnings of orgasm lie in the ‘Yes!’ factor of gene continuation, in How Women Got Their Curves and Other Just-So Stories: Evolutionary Enigmas David Barash and Judith Lipton believe it could be, at least for the potentially multi-orgasmic female, an “anti-infanticide insurance policy” that spurred women to mate successively with multiple males, or, more likely in the authors’ opinions, an evolutionary mechanism for monogamy (link to chapter five from the aforementioned book, titled The Enigmatic Orgasm).

As Robin Hanson explains quite succinctly, female orgasm could be evolution’s way of allowing females to screen prospective mates—a method of enabling females to discover the most compatible and suitable males.

First suggested by David P. Barash nearly three decades ago, the idea is that orgasm might be a way a woman’s body speaks to her brain, “telling herself” that she has been having sex with a suitable partner—that is, one who is not worried about being displaced by a competitor, who is self-confident and unhurried enough to be satisfying to her. […]

Research on a large captive group of Japanese macaque monkeys is also suggestive. […] During 238 hours of observations in which 240 copulations were observed, female orgasmic responses occurred in 80 (33 percent). Of these orgasms, the highest frequency took place when high-ranking males were copulating with low-ranking females, and the lowest between low-ranking males and high-ranking females. […] Maybe, [female orgasm] is designed to be more than a little hard to get, adaptive precisely because it can’t be too readily summoned, so that when it arrives, it means something. […]

What about faking orgasm? […] Orgasmic pretense might increase the man’s confidence regarding paternity of any offspring, building on his likely assumption that a sexually satisfied woman wouldn’t have sought to mate with someone else. […] [This] would diminish the likelihood that the man will engage in “mate guarding,” thereby facilitating a woman’s ability to engage in extrapair copulations. […]

Rates of extrapair paternity are about 2 percent in many human populations and about 10 percent in traditional societies. … One study has found that women are significantly more orgasmic when paired with men who are more symmetric. […] [and] are more likely to experience ostensibly “high sperm retention orgasms” – that is, climaxes that occurred in close temporal proximity to the man’s.