“Men tend to want many more sex partners than women do.”
~ Susan Hughes, Archives of Sexual Behavior (2021)

Most of my writing these days is in response to authors on Medium who write about relationships, gender, and sexuality. This community is 80% female. Their “voice” leans feminist and culturally progressive. Carlyn Beccia has been a favorite in this space. She covers many subjects, deeply considered with humor and aplomb — writing that sparkles underneath her own unique illustrations. Occasionally we butt heads; she dismisses and sometimes denigrates evolutionary psychology (EP) and my understanding of mate selection science.

Her latest piece was “Nature Makes Men More Promiscuous is an Evolutionary Biology Myth.” This piece is mainly about the number of sex partners reported by men and women. Beccia asserts that men and women are equally promiscuous, as revealed by research from evolutionary biology. I could not let this go unchallenged. Below is my response to her. My post would make more sense if you read her piece, but I think my statements of fact and opinion stand alone in their retort and rebuke.

Promiscuity Assertions Hurt Women More Than Men.

Becca’s first point. I agree. “Slut-shaming” is unfair and uninformed.

Darwin Revisited

Charles Darwin was not right about everything related to non-human species. Still, in the human population, he was right in his speculations about male desire and interest in multiple partners for sexual reproduction.

“Just So Stories” — An Old Criticism of EP Methodology

“Just so stories” is a “bullshit” (using Beccia’s aggressive word choice) and snarky framing of evolutionary science methodology – a worn-out trope. What Beccia describes as a “just so story” (women’s biological investment in children, etc.) is the way it is. Yes, as Beccia notes sarcastically, “sperm are cheap, and eggs are expensive.”

Women Are More Choosey – Full Stop

Women are more “choosey” than men for sexual partners. This comports directly with the evolutionary science of sexual selection and pretty much every single study of modern sexual selection dynamics, including the latest studies of dating apps. To think otherwise is indeed “bullshit.” (Speaking to Beccia) “hell, use yourself and your girlfriends as anecdotal evidence.” Men find the majority of women attractive. Women find the majority of men unattractive.

Women Are Just Not as Promiscuous as Men

Women are just not as promiscuous as men; that would make no sense for children’s survival and the need for paternal certainty. (I will not itemize here the numerous studies that show the difference between men’s and women’s sex “drive” as evidenced by thoughts, fantasies, spontaneous arousal, masturbation, and willingness to engage in sex.) Interestingly, Beccia and other female authors want to take on the badge of promiscuity. To prove what point? A sign of female empowerment? A way to assert that there are no sexual or biological differences between men and women?

Women Do Have More Opportunity

Women have enormously more choices, sexual access, and sexual opportunity than men, but they generally do not act on it. Sexual opportunity is different from a sexual mating strategy. Men and women are typically on opposite sides of that coin.

Rates of Infidelity and Number of Affairs

Rates of infidelity are indeed narrowing between men and women. Recent studies show that men cheat with a more significant number of partners, and women are choosier even in this domain, typically having a single affair.

Numbers on the Bed Post

EP researcher David Schmitt studied 16,288 individuals residing in 52 nations and found that men said they wanted 1.87 sex partners over the next month; women wanted only .78. (He also found agreement of findings across all nations and cultures.)

Ten Partners or One Partner Ten times?

Susan Hughes’ research (2021) in the Archives of Sexual Behavior found (in a very clever design of choosing, in a continuum, between sex with one partner ten times vs. sex with ten partners one time) “in most cases, the women allotted all ten dates to only one or two men.” Concluding, “The results of this study seem to confirm the observation that men tend to want many more sex partners than women do.”

Male Overestimation and Over-perception Bias

Yes, men overestimate the number of their partners, and women underestimate their number because of the bias against female promiscuity. Men’s inflation is somewhat related to the psychological phenomenon of over-perception bias – a belief that women may possibly (aka the movie Dumb and Dumber) be interested in them romantically and sexually. This sexual section phenomenon is related to error management theory; a man cannot afford a false negative result: NOT pursuing a woman (egg) who might otherwise be interested if a pursuit had taken place.

The Difference in Reporting Numbers of Sex Partners Has Four Causes

1. Promiscuity bias (above), also cited by Beccia in the Alexander and Fisher “bogus pipeline” study. That study had an unimpressive subject sample of 293 General Psychology students.

Most Importantly!

2. Women are having sex with the same lucky small subset of men.

Studies from dating apps reveal that the top 78% of women are fighting over the top 20% of men.

Essentially, multiple women are having sex with the same man: one man has sex with five women. He accurately reports five partners. Each of the five women accurately reports one partner.

Reproductive Variance

Reporting of the number of sex partners is not only influenced by the overreporting by men and underreporting by women but, more importantly, by the operation of a “micro” version of the macro reproductive variance phenomenon, i.e., more women are having sex than the number of men having sex, by perhaps a large margin. Researchers call this the modern male sexual deficit. The number of women who have sex is more than the number of men who have sex.

More Mothers Than Fathers Throughout History

The macro reproductive variance refers to the variability of reproductive success for human females and males throughout human history. The difference between men who do not reproduce (the have-nots) and those who reproduce prolifically (the haves) is vast. DNA studies by Jason Wilder and colleagues revealed that approximately 80% of women in human history have reproduced (have children), compared to 40% of men. More women are mothers than men are fathers. The human population is descended from twice as many women as men. A few men are siring many children (the Genghis Khan effect).

College Dating Environment – Slightly Better Deal for the Average Guy

One unique dating environment (mating pool) is on modern college campuses, where the sex ratio is approximately 60% women to 40% men. On college campuses, women lower their standards a little bit. They are slightly less choosey. With that ratio, more men of lower mate value/attractiveness get to have sex than in the average population. But even there, the most attractive guys get most of the action.

On the Other Hand – More Women Are Having Sex With Each Other!

3. The mathematical asymmetry of the number of reported partners by men and women (in some reports) is also because more women are having sex with women and not men!

4. Finally, according to Kristen Mitchell (Journal of Sex Research), men might include non-penetrative sexual encounters in their tally of sex partners. Women did not. Hey women, cunnilingus and fellatio are not sex?

Male Promiscuity Can Negatively Affect Genetic Legacy

It is true (as Beccia implies) that there is a point at which male promiscuity negatively affects the survival of his children. Children need the support of both parents to secure a genetic legacy.

Will Not Debate Bateman’s Principle Here*

I will spare the reader an attempt to unpack Beccia’s assertion that geneticist Angus Bateman cherry-picked his data or the integrity of Patricia Gowaty’s biology lab at U.C.L.A. But I don’t believe the studies of fruit flies or even other primates are decisively instructive or preclude the vast evidence related to human sexual selection and reproduction. Yes, the research on the mating habits of non-monogamous female birds is notable, but birds are not homo sapiens. Humans have a 9-month gestation and prolonged infant dependency.

The Coolidge Effect** Is Real

But if you want to use primates, the Coolidge Effect holds up. And it is operative for human males. Novelty works for both sexes, but it is compelling for human males. Beccia’s post does not really dispute the truth of the Coolidge Effect. It is worth noting that women need more novelty inside a pair bond than that required by a man because male sexuality is less complicated.

The Honeymoon Effect

The “honeymoon effect” – bonds caused by the “love hormone,” oxytocin, is also real. But oxytocin is more instrumental to women’s sexuality and sexual functioning than to men’s. (This leads to the conversation about the female orgasm as a male mate selection strategy –- female orgasm increases the chance of being chosen and being retained as a mate.)

Honeymoon Effect Coexists with Coolidge

Bottomline: the honeymoon effect does not preclude the male need for partner novelty; it does not contradict the operation of the Coolidge Effect.

What is Beccia’s Beef – Really?

Finally, I do not understand Beccia’s psychological schema around these issues. Why does she refuse to accept the evolutionary and biological science of human sexual selection and human sexuality? Why does she misrepresent the claim and evidence of evolutionary psychology? EP is not “bullshit.” “Boys will be boys” is never uttered by reputable researchers in this field. Beccia is an empowered woman. She is probably sexier and more sexual than average. Good for her. Many men desire her, no doubt (she is quite attractive), but I bet she chooses very few. Beccia probably exists on the robust side of the bell curve from the average woman in terms of sex drive/desire, access, and socio-sexuality.

Rectify Inequities – But Don’t Blur Biological Distinctions Between Male and Female

I have studied the hard biological science of aggregate populations throughout human history. I study researchers who do not, as a rule, have an agenda or bias to shape the nature-nurture debate in favor of women to rectify historical power inequities. The Beccia post is representative of this bias. Let’s rectify power inequities without blurring the biological distinctions between males and females. 

*Bateman’s principle (in evolutionary biology): since males produce millions of sperm cells with little effort and females invest much higher energy levels to nurture a relatively small number of eggs, the female plays a more significant role in their offspring’s reproductive success. Bateman’s paradigm views females as the limiting factor of parental investment, over which males will compete to mate successfully.

**The Coolidge effect is a biological phenomenon seen in animals whereby males exhibit renewed sexual interest whenever a new female is introduced, even after sex with prior but still available sexual partners.