Sex At Dawn Is Right

I like to think of myself as courageously seeking out important truths, however uncomfortable. But like most would-be-courageous folk, I don’t really know what I want until I get it. I was excited to read the contrarian Sex at Dawn, which suggests sexual promiscuity is our forager heritage. But that pretty sparkler was really a grenade – its uncomfortable truths shook me to my core.

To hear a different view, immediately afterward I read Evolutionary Biology of Human Female Sexuality [EBoHFS], which supports a standard view of foragers as long-term pair-bonders. By comparison, EBoHFS is more academic: dry, clinical, verbose, and careful to define terms and consider many possibilities. It reviews an immense number of studies, and appears to takes a cautious middle ground.

Sex at Dawn, in contrast, frustrates academic sensibilities. It is passionate, partisan, even snide. It doesn’t systematically review evidence pro and con, or points of view, and it takes long detours to settle scores with opponents. It is long on anecdotes and examples, relative to systematic data. Its authors are confused on how economists use “selfishness”, and on basic Malthusian population theory; they aren’t really to be trusted on theory. Furthermore, their relationship advice seems flippant.

But on their key claim, that forager females were sexually promiscuous, I am persuaded: they are basically right. EBoHFS hardly offers any contrary evidence, it just keeps repeating that evidence is ambiguous, while embracing the usual story by default. (Sex at Dawn also gets forager peacefulness right – see Chapter 13.)  Searching for expert critical reviews, the closest I found were this and this, which mainly just complain it is all very complex and no simple generalizations apply.

The basic facts are these. Recent humans mostly had long-term pair-bonds, while our two closest primate relatives, chimps and bonobos, are quite sexually promiscuous. Yes, they hardly mate at random, and may return often to favorites. Even so:

“Among chimpanzees, ovulating females mate, on average, from six to eight times per day, and they are often eager to respond to the mating invitations of any and all males in the group. … A recent study … showed that more than half the young (seven of thirteen) had been fathered by males from outside the female’s home group.” [p70]

Bonobos females are even more promiscuous. In fact, to find biological analogues to recent human monogamy, EBoHFS looks to various kinds of birds; mammals won’t do. “Monogamy is not found in any social, group-living primate.” [p64]

The big question then is when did the biologically-rare (3% of mammals) phenomena of (near) monogamy arise in our lineage, millions of years ago with the rise of humans, or ten thousand years ago with the rise of farming? And since our data on modern foragers suggests that farming at least greatly reduced promiscuity (especially for females), the big question is really whether lightning struck once or twice, i.e., if there were one or two big unprecedented moves away from typical social-primate promiscuity. Occam’s razor suggests one lightning strike.

If human sex were like chimp and bonobo sex, how should we expect it adapt to human changes, like larger brains, group sizes, and lifespans, and more egalitarian sharing? Dunbar says brain size, group size, and grooming time fraction correlate, and says language let humans better “groom” our record size groups. If sex was part of “grooming”, we’d expect humans to spend a record fraction of time on sex. We should also expect more adaptations to longer term relations (like pedophilia).

So what is the data? Humans spend more time having sex than any known species. Human sex shares many otherwise-rare features with the promiscuous bonobos, who hide their fertile days and have sex all month long, in many positions including missionary where they gaze into each other’s eyes and kiss deeply. Bonobos share food with sex, and use sex for social bonding, such as via homosexuality. Human sex has many other features understandable as adaptations to promiscuity, including large external testicles, a record size penis designed to scoop away other semen, men preferring high male-to-female ratios in porn, long frequent sex, and women being louder and lasting longer than men.

Monogamy vs. promiscuity is a rare area where academics and cultural elites tend to favor the conservative/farmer side of the forager vs. farmer divide. While I find myself balking at the idea of embracing sex partners with forager promiscuity levels, I accept that this preference was culturally imprinted on me.

Many Sex At Dawn quotes below the fold:

The only American scholar to have been cited by each of the three intellectual giants of his century, Darwin, Freud, and Marx, many consider [Lewis Henry] Morgan the most influential social scientist of his era, and the father of American anthropology. … Morgan … hypothesized a far more promiscuous sexuality as having been typical of prehistoric times. “The husbands lived in polygyny, and the wives in polyandry.” [43] …

No animal spends more of its allottted time on Earth fussing over sex than Homo Sapiens. … [In contrast,] pair-bonded “monogomous” animals are almost always … having sex … infrequently, quietly. [85] … Female primates are highly attracted to novelty in mating [p.96] … The total number of monogamous primate species that live in large social groups is precisely zero. … The few monogamous primates that do exist (out of hundreds of species) all live in the treetops. Primates aside, only 3 percent of mammals and one in ten thousand invertebrate species can be considered sexually monogamous. [97] …

Modern men’s testicles are smaller than those of chimps and bonobos, yet they put those of polygynous gorillas and monogamous gibbons to shame … The argument that modern men’s testicles would be as big as the chimps’ if we’d evolved in promiscuous groups is founded on a crucial and erroneous assumption: that human testicles haven’t changed in ten thousand years. … Testicular tissue in humans, chimps, and bonobos (but interestingly, not gorillas) is controlled by DNA that responds unusually rapidly to environmental changes. [227] …

[Why is it] male ejaculate that puts the money in money shot. … Images and videos showing one woman with multiple males are far more popular on the Internet and in commercial pornography than those depicting one male with multiple females. … Why does being cuckolded consistently appear at or near the top of married men’s sexual fantasies.? [231] …

“In primates which live in family groups consisting of an adult pair plus offspring the male usually has a small and relatively unspecialized penis.” …”Adult male humans have the longest, thickest, and most flexible penises of any living primate.” … The unusual flared glans of the human penis forming the coronal ridge, combined with the repeated thrusting action …creates a vacuum .. [that] pulls away any previously deposited semen. … Men last far longer in the saddle than bonobos (fifteen seconds), chimps (seven seconds), or gorillas (sixty seconds), clocking in at between four and seven minutes, on average. [235] …

The very existence of the external human scrotum suggests sperm competition in human evolution. Gorillas and gibbons, like most other mammals that don’t engage in sperm competition, generally aren’t equipped for it. A scrotum is like a spare refrigerator in the garage just for beer. … Anyone who’s been kicked in the beef fridge can tell you this is a potentially costly arrangement. [237] …

Researchers found “marked differences in testis size among human races. … This range is far beyond that average racial differences in body size would predict. [241] … Coming in at hundreds or thousands of copulations per child born, human beings out copulate even chimpanzees and bonobos. … When the average duration of each copulation is factored in, the sheer amount of time spent in sexual activity by human beings easily surpasses that of any other primate – even if we agree to ignore all our fantasizing, dreaming, and masturbating. The evidence that sperm competition played a role in human evolution is simply overwhelming. [242] …

When it comes to sex, men may be the trash-talking sprinters, but it’s the women who win all the marathons. … If men and women evolved together in sexually monogamous couples for millions of years, how did we end up being so incompatible? [245] …

Why is it that from the Lower East Side to the upper reaches of the Amazon, women are far more likely than men to loudly announce their sexual pleasure for all to hear? … “In a wide variety of species, females vocalize just before, during, or immediately after they mate. These vocalizations,” Semple says, “are particularly common among the primates and evidence is now accumulating that by calling, a female incites males in her group.” … Before you conclude that female copulatory vocalizations just a fancy phrase for a little excitement, think about the predators possibly alerted by this primate passion. [256] …

As with the complex penis and external testicles in the male, the elaborate filtering design of the human [female] cervix points toward promiscuity in our ancestors. [265] … Primate species with orgasmic females tend to be promiscuous. [268] …

[Researchers] exchanged that season’s newborn sheep and goats (the baby sheep were raised by adult goats, and vice versa). Upon reaching sexual maturity a few years later, the animals were reunited with their own species and their mating behavior was observed. The females adopted a love-theone-you’re-with approach, showing themselves willing to mate with males of either species. But the males, even after being back with their own species for three years, would mate only with the species with which they were raised. [272] …

Whether they were watching men with men, women with women, … their genital blood was pumping. But unlike the men, many of the women reported that they weren’t turned on. … This disconnect between what these women experienced on a physical level and what they consciously registered is precisely what the theory of differential erotic plasticity predicts. [273]

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  • Salem

    “Images and videos sowing one woman with multiple males are afar more popular on the Internet and in commercial pornography than those depicting one male with multiple females”

    Really?

    I don’t know how you’d test this claim, but my impression is just the opposite.

    • chris

      Even if true, it may not reflect preferences so much as economics. According to wikipedia, a male porn star takes home $40k/year. A female takes home $100-250k.

      (Their numbers seem mostly anecdotal, however.)

      • Matt

        That could be about demand though. Men are the consumers of pornography and would prefer to see women. Couldn’t that account for higher female salaries just as well as men preferring females with multiple males?

  • http://rationalmechanisms.com/lexicon DWCrmcm

    Among chimpanzees, ovulating females mate, on average, from six to eight times per day, and they are often eager to respond to the mating invitations of any and all males in the group. … A recent study … showed that more than half the young (seven of thirteen) had been fathered by males from outside the female’s home group.” [p70]

    Okay, this is a juxtaposition, |:|.
    The Text |:| our capacity.
    This is of course a surrealism.
    Let’s get all RMCM about this.

    Consider an Innate juxtaposition :

    Species A |:| Species B

    This too is a surrealism.

    To find the metaphors within the surrealism we need a container.
    That is as much as I can spontaneously disclose.
    It won’t be that long now, a few months, Promise

    Consider also
    Species A and Species B have different sexual extense and scope.

    The indifference of male chimpanzees to the scope-al behavior of females, arises from their Brain being still “tightly bound to the machine”.

    The indifference of male Humans to the extense-al behavior of females arises from their brain being now “loosely bound to the machine”.

    Respectfully
    dwc RMCM™
    God bless

  • blake r

    I was turned off by the book’s tone and the authors’ misunderstanding of some basic facts, but I agree the conclusions are essentially correct.

    If you haven’t already, look up Sarah Hrdy’s Mothers and Others. Her argument that humans are cooperative breeders subsumes the discussion of sexual promiscuity. Because children are in need of such intensive care, parents should be capable of forming a strong pair bond if no one else is available. However, in stable communities with aunts, sisters, and grandmothers, the father becomes less important. The grooming aspect of sex solidifies support for a woman’s children. Better to diversify than invest in a single partner. Because of the contingent nature of care, children have to be closely attuned to intention, pointing to another source of our theory of mind.

  • http://manwhoisthursday.blogspot.com Thursday

    I will have to read the book, but from summaries I’ve read it seems that to quote Eysenck on Freud what is true in the book is not new and what is original in the book is not true.

    I’d still defend the following propositions:

    1. Women are often promiscuous, but they are significantly less promiscuous than males.

    2. The past was not a egalitarian polyamourist paradise, because polyamoury is really a disguised form of polygyny.

    3. Jealousy and mate guarding started very early in human history as they Darwinian incentives for them to evolve are just too strong.

    • LeBleu

      What is your basis for claiming that polyamory is disguised polygyny? Most of the sources I’ve seen claim relative equality, or even a slight polyandrous tendency.

      I would agree on the past not necessarily being egalitarian, that seems like a modern rich society thing.

      • http://manwhoisthursday.blogspot.com Thursday

        1. Modern free love communities have invariably granted a disproportionate amount of the sex, especially with the younger women, to the few high status males, no matter how egalitarian their ostensible ideology.

        2. Natural selection favours those women who mate with the few men with the best genes.

        Do you have any studies with numbers to contradict that?

      • http://www.chiliahedron.com Relsqui

        Why look at “free love communities” rather than private personal relationships? There are certainly more of the latter, and they are by definition less artificially constructed than the former.

    • http://www.chiliahedron.com Relsqui

      “Women are often promiscuous, but they are significantly less promiscuous than males.”

      Be careful conflating an observation about general trends in history with the behavior of modern individuals. Obviously they’re correlated, but careful language is called for to avoid the minefield of predicting or rationalizing behavior that’s not presently acceptable based on the conditions under which it evolved. (The classic example, of course, is male infidelity.) Otherwise a conversation can easily get derailed into piggish nonsense. I’m sure you didn’t intend to convey that conflation, but if I weren’t assuming good faith, this choice of words might not have made that clear.

      • Kirkus

        It’s my understanding that in a study where females were deceived into thinking they were being monitored by lie detector, they reported having extramarital affairs at a higher rate than the average reported rate of male’s infidelities. This would indicate that females are more careful in hiding their infidelities.

      • Mike

        Interesting. Do you have a link to this study?

    • http://hanson.gmu.edu Robin Hanson

      I don’t think you disagree with the book.

  • blake r

    re: Salem

    A highly unscientific number, but on one site (XVideos), there are more than 8 times as many videos tagged with ‘mmf’ as ‘mff’. However, the ‘group’ tag, which is significantly larger than either of those two, appears to have a high female-to-male ratio at first glance. Result: ambiguous.

  • Aron

    I found the quote on female vocalization during copulation interesting. It’s possible this pattern has been observed in folk treatments of the subject.

    e.g. (NSFW) http://www.skeetfighter.com/

    Alpha Male w/ violent tendencies: “What if someone sees us?”
    (Second male is shown observing from the shadows)
    Aggressive Female: “I hope someone does. That gets me so hot.”

  • Neal W.

    Robin,

    Could you provide the reference for this?

    “Why do so many heterosexual men get off on pornography featuring groups of guys having sex with just one woman? … [and why is] it’s male ejaculate that puts the money in money shot. … Images and videos sowing one woman with multiple males are afar more popular on the Internet and in commercial pornography than those depicting one male with multiple females. … Why does being cuckolded consistently appear at or near the top of married men’s sexual fantasies.? [231] …”

    I have no cuckold fantasy, nor do I like many men on one woman porn (I don’t even like two men on one woman). Neither have my male friends ever expressed an interest in these things.

    • JS Allen

      Virginie Despentes used to work for the porn industry (and as a prostitute), and discusses the prevalence of mmf/gangbang/etc. porn at some length in her book “King Kong Theory”. The skewed ratio is a well-known fact that should be evident to any aficionado, especially in foreign stuff.

      However, I don’t think the observation about porn ratios is all that significant. It’s partially just a restatement of the observation Robin quoted about men being sprinters and women being marathon runners. The higher the female to male ratio, the more you have females sitting idle waiting for a turn — and the females are supposed to be the stars, right? Having females on screen who aren’t being utilized is just stupid, and if the guy is going to serially perform with girls who are waiting off stage, you might as well just have a bunch of short movies.

      Additionally, you could use the same argument to say that sodomy or other common sub-genres were part of our evolutionary past, since those are so common in porn (certainly I can think of a few genres that are far more common than mmf which would have no bearing on evolution). So it doesn’t really make a lot of sense to infer evolutionary history from modern porn preferences.

      Finally, I don’t think there is any empirical evidence supporting the idea that men fantasize about being cuckolded. I’m pretty sure it’s the opposite — men fantasize about cuckolding other men, if they think about it at all. The cuckoldry bit sounds like Freudian psychobabble.

      • Cyan

        Finally, I don’t think there is any empirical evidence supporting the idea that men fantasize about being cuckolded.

        You obviously don’t read Dan Savage. Check out this column.

  • JS Allen

    Also, I don’t know why this would leave someone “shook to the core”. Evolution has endowed us with all sorts of innate impulses that wehave chosen to overcome through culture and education.

  • Riaz

    Even if group sex videos involving multiple men and a single women are the most popular type of pornographic videos, it doesn’t necessarily support the conclusions of the book. For example, it could just be that those types of videos are popular because the female is signaling availability.

    • Gil

      Or men who frequent porn sites aren’t representative of the norm?

      • nick012000

        Actually, people who watch porn probably are, given how big and relatively mainstream the porn industry’s gotten. I’ll say from personal experience, though, that the fantasy that MMF porn evokes in me is one of degrading and humiliating the woman in question. It’s also one wherein the fantasizer identifies with all the men present; he’s not being cuckolded, he’s simultaneously fucking the woman in every hole she has.

      • Salogan

         General Motors is the largest pornographer.  The “hot channel” is broadcast through its DirectTV satellite service.

        Pornography is a huge industry. With all kinds of permutations. Exactly what does that suggest about the basic nature of human sexuality, or the evolution of our society?

        If nothing else, an overwhelming need for stress reduction.  Enforcing monogamy is a huge stressor.

  • JamieNYC

    Robin, adding to J S Allen’s comment, I’m not sure why you feel shaken. We are direct descendants of the (mostly) monogamous ‘farmers’. What came before them was different. Are you also shocked that we descended from ‘apes’? In my view, people who use the new insight into per-agricultural human behavior to justify/rationalize certain patterns of behavior today are making an obvious logical error, just as if they advocated walking on all fours because our ancestors a few million years ago walked that way.

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  • http://t-a-w.blogspot.com/ Tomasz Wegrzanowski

    That is the evidence? Anything even mentioning chimpanzees and bonobos is just ridiculous. You couldn’t get more irrelevant than that.

    Difference between Late Paleolithic humans and chimpanzees is 100x as great as difference between Late Paleolithic humans and Neolithic humans.

    This line of reasoning isn’t just inconclusive, it’s pure nonsense.

  • Jason Malloy

    Genetic, behavioral, and anatomical evidence does not support high levels of promiscuity in human deep history. This would result in e.g. higher levels of sexual dimorphism, larger testes size, and narrower paternal lineages (all evidence of much more turbo-charged male sexual competition). Humans have always been mildly polygynous.

    Extant forager groups remaining in Africa (the approximate evolutionary environment) are all strong pair-bonders, while foragers outside of Africa vary widely in their behavioral profiles, but on average they are somewhat violent and promiscuous. These are Holocene foragers, adapted to novel ecological circumstances, and are not representative of ancestral foragers. (This is also why I take issue with War Before Civilization; which also bases too much on Out-of-Africa foragers.)

    A priori, we should expect are ancestors to resemble the Hadza more than Australian natives.

    • http://hanson.gmu.edu Robin Hanson

      Our sexual dimorphism is comparable to promiscious chimps & bonobos. Current testes are large, and may have shrunk in last 10Kyr.

      • http://rationalmechanisms.com/lexicon DWCrmcm

        Actually,
        We are now sexually polymorphic – coitus and n vitro-fertilization, and eventually virtual source insemination. – DNA designed and built from the ground up by Fourth Experiences aka(AI).

        Gender has completely abstracted

        Homosexuals, transsexuals, bisexuals, pedophiles, voyeurs, fetishists, sadists, masochists (see Freud for more).
        Mutated atavism. Innate Condition

        we have sexual introverts, sexual extroverts, celibates (see Jung for more).
        Auto-Erotic asphyxiation.
        Sex with infected partners.
        Behavioral atavism, Intrinsic condition.

        And we have religious, ideological, secular, and phobic sexual differences.
        Atavistic thinking – Abstract Condition.

        just saying …

        Respectfully
        dwc RMCM™
        God bless

      • Chris

        A very interesting read.

        http://www.putslab.psu.edu/pdfs/puts_10_beautybeast.pdf

        “note that the sex difference in upper-body muscle mass in humans is similar to the sex difference in fatfree mass in gorillas (Zihlman & MacFarland, 2000), the most sexually dimorphic of all living primates.” page 5 of the linked article.

        Furthermore, it is my understanding that the ratio of human testes to body size is intermediate between that of gorillas (a highly polygnous species) and chimpanzees (a highly promiscuous one).

        “As a proportion of body weight, human testes are more than twice as large as those of gorillas, suggesting some degree of sperm competition (in comparison, human testes are about one-third the size of chimpanzees; Smith, 1984).” From page 2 of http://www.epjournal.net/filestore/EP083136.pdf

      • ra6

         In terms of mass males and females are similar size. Human females have larger fat stores, because human infants require more nutrients. So if you check the ratio of muscle mass purely we are closer to gorillas.

  • Jason Malloy

    Oops …our ancestors.

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  • http://zatavu.blogspot.com Troy Camplin

    Our oxytocin levels are equivalent to other monogamous mammals, not to polygamous mammals. Our sexual dimorphism suggests males should have about 1.5:1 female to male ratio. This of course says little about male promiscuity, though, other than to suggest that men naturally have a mate and a mistress. Nor does it say much about female promiscuity. One can have strong pair bonds created by oxytocin while also engaging in extramarital matings. In other words, you seem to be conflating polygamy with extramarital sexual relationships. They are not the same.

  • fructose

    The porn thing is just loony. I suspect it is just an artifact of super-stimulus. People who watch a lot of porn need more and more stimulation, so the scenes just get more and more intense–in all dimensions.

    Really, citing anything in modern pornography as representative of human sexual preferences is crazy. There are so many different fetishes out there, you could use porn to support any claim.

    • Doug S.

      Also, consider the prevalence of porn that has no males in it…

      • Guest

        As someone who used to work in video distribution, it’s actually relatively rare to find whole movies it even scenes exclusively featuring women. ‘Lesbian’ acts aplenty, but almost always punctuated by one or more male performers.

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  • Manto

    Her cheating on you is exactly as likely*damaging as your fear of it suggests. Think of it like the “probability*cost=expected cost” equation. If we could measure the magnitude of the fear and the cost of being cuckolded, we might be able to get a reasonable estimate for the likelihood.

    Big testicles, semen composition (part coagulate, part sperm, part chemical gifts, part chemical warfare), penis as scoop… clear signs that our women are promiscuous.

    It occurs to me that involuntary female sex noises could just as easily be honest signals of trustworthiness as invitations to other males to get their entry into her vaginal lottery. (If the noises are involuntary and you haven’t heard them before and she doesn’t have a reputation from being heard, you can be reasonably sure she hasn’t had a lot of sex. Plus, it’s more difficult for her to cheat on you without you finding out. Call this the “car alarm” explanation for female moaning/screaming.)

    • ra6

       Human testicals are certainly larger than gorillas, but not nearly the size of Bonobos or Chimpanzees. The penis scoop is actually the result of humans losing the barb on the end of the penis. Losing the barbs is the reason copulation takes longer. Which is further evidence against the Bonobo mating theory, since copulation is dangerous, and it takes much longer without the spines, women could not afford to get a train run on them every time they ovulate.

  • http://rationalmechanisms.com/lexicon DWCrmcm

    “(If the noises are involuntary and you haven’t heard them before and she doesn’t have a reputation from being heard, you can be reasonably sure she hasn’t had a lot of sex. Plus, it’s more difficult for her to cheat on you without you finding out. Call this the “car alarm” explanation for female moaning/screaming.)”

    Just a minute please.
    Now, I “am” way way way outside the box, born that way, and I am mentally ill.

    notwithstanding the above

    You are reaching. ecstasy

  • Philo

    “The big question then is when did the biologically-rare . . . phenomena of (near) monogamy arise in our lineage, millions of years ago with the rise of humans, or ten thousand years ago with the rise of farming?” You have come to believe that the answer is *ten thousand years ago*. Why did this “shake you to your core” (echoing JamieNYC)? “While I find myself balking at the idea of embracing sex partners with forager promiscuity levels, I accept that this preference was culturally imprinted on me.” Well, no doubt culture was important in forming your tastes. But ten thousand years is a long time; there probably have been significant genetic changes, too. (Admittedly, many of your ancestors probably did not take up farming till, say, three thousand years ago, but that’s still a long time. And genetic change has been accelerating with the increase in population.)

    How do chimps and bonobos provide for the care of pregnant females, nursing mothers, and infants, if no particular male takes responsibility? Would their system work for human beings, especially for anatomically modern human beings, of which the pregnant women, nursing mothers, and infants require much more care? (These questions prompted by simple ignorance.) My guess is that pair bonding was developing among our ancestors much earlier than farming, *pari passu* with extended pregnancy and nursing and greater helplessness of infants. (Admittedly, some sort of collective social system of care might be possible. Also, as blake r remarks: “Better to diversify than invest in a single partner.” In short, there is conflicting evidence.)

  • Jason Malloy

    Dr. Hanson,

    I left two comments here yesterday that have either disappeared, or gotten trapped in a spam filter.

    • http://hanson.gmu.edu Robin Hanson

      You repeated a long previous comment of yours word for word. A simple link should be sufficient.

      • Jason Malloy

        Really, you deleted my comment? That sucks.

        I think you misread it, it wasn’t primarily a quote.

  • Vlad

    It seems to me that most of this evidence is compatible with the standard view of monogamy + plenty of cheating. The adaptations for sperm competition only imply cheating, rather than group sex. The only exception is the fact that it takes longer for women to achieve orgasm. This is interpreted as an adaptation for group sex. Could it be just a side-effect of something?

    Here’s a just-so story to explain away this evidence against the monogamy theory: As mentioned in the quote, orgasm vocalization might not be a good idea as it attracts predators – so, perhaps women evolved to avoid reaching orgasm, by delaying it. Other benefits of not reaching orgasm in the ancestor environment might include the ability to move on with other business quickly. Under this theory, women still have the ability of having orgasm for the same reason that men have nipples.

    It seems that all evolutionary theories of human sexuality are bound to be controversial in one way or another 🙂

  • J Mann

    Robin, why are you so confident that SAD got forager peacefulness right? Isn’t that one of the points that your second linked review said was challenged by some of the evidence?

  • J Mann

    Nevermind, maybe – if I’m reading the links right, the emerging consensus seems to be that “simple hunter gatherer” societies in pre-history probably had murder, feuds, and maybe raids, but not “war”, if war is defined as a conflict designed to kill unidentified members of a rival group. “Complex hunter gatherer societies” may have had war. Is that more or less what SAD says?

  • Primate

    A few points…

    Ryan has been put right on his own Psychology Today site:

    When ovulating male hierarchy matters more than sperm competition.

    Female bonobos do not copulate more than female chimpanzees. Chimpanzee mating is more concentrated and bonobo more spread out – female bonobos mate less when fertile and with fewer different males as they have more mate choice. Sexual coercion is common in chimpanzees. In fact, females mating with mutilple males is often a result of avoidance of injury from males across species. It is also to avoid infanticide by males.

    Read this, for example, to get more understanding about bonobos.

    “Mothers matter! Maternal support, dominance status and mating success in male bonobos (Pan paniscus) ”

    If we were like bonobos we would have weak male-male bonding and the most important bond would be that bewteen mother and son as this is what is behind reproductive success in bonobos.

    Most bonobo ‘ sex’ is non-erotic and non-ejaculatory. The rubbing of genitals is no more than the equivalent of a hug or handshake to relieve stress. We also do not touch and rub the genitals of infants and children – at least not legally.

    Almost all mammalian testes are external, regardless of size.

    Ryan only has a very cursory knowledge of primates and evolutionary biology and sexual selection.
    He also has some strange fantasies about things such as men desiring to be cuckolded. What I think he is confusing is the male willingness to ‘share’ the casual, short-term mates ie the ‘sluts’ and the male intent to mate-guard the long-term mate/ mother of offspring that he will support.

    What he also fails to mention is the jealousy that exists in tribes such as the Ache where there are more than one father – as men often die and children are then killed if he is the only father, extra possible fathers prevent the killing of those children and provide for them. But even here wives get a beating for their extra-mating and if there is more than one or two other possible fathers then none will help the chidren so they perish too.

    While we are not obligate monogamous, and both sexes have optimal strategies of mating outside the pair bond, we also have optimal strategies of preventing such behavior by our mate. We are not like bonobos and much more like chimpanzees in almost every way. No species has sexual behavior that is conflict-free sharing of females. No species has conflict-free sex.

    As Ryan accepts that females find fewer men sexually attractive than males find females he needs to consider the how the imbalance of numbers is meant to work. The men, too, will be competing for even a smaller number of females as older females are far less attractive to men. There will inevitably be competition between men for access to the relatively small number of sexy/fertile/available females which will mean competition for resources/status etc to win in that competition. Simple numbers and variation in attractiveness of males will make sure of that.

    Finally, if he is right then men must first show that they are not concerned with knowing their biological children or any of us in knowing our biological fathers. We should stop the taking of the husbands/’father’s’ name by children for a start. And women would have to be sure that they will not be harmed for taking lovers as sexual control of females is the main cause of battery of females around the world – just like in chimpanzees. See eg:

    “Evolution of Sex and Reproductive Strategies”

  • Primate
  • Barbara Saunders

    My (unscientific but reasonable, I think) hypothesis: the extended family was an adaptation to the agrarian world, which enabled a rise in standard of living. The nuclear family was an adaptation to 20th century corporate-industrial world, which enabled another rise in standard of living. The clan or tribe we evolved for is re-emerging because in the networked world, it once again aligns with the potential for a rise in standard of living.

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  • http://blog.seliger.com jseliger

    There’s now a longish scholarly review of Sex at Dawn at Evolutionary Psychology: http://www.epjournal.net/filestore/EP09325335.pdf , which is overall more positive than I expected.

    • http://hanson.gmu.edu Robin Hanson

      Worth reading.

  • Robert

    When asked about the religious implication of the book the author declined to get into the fray.
    I think it proves nearly all our religions have been hijacked by the state to preach the party line. You see if we as humans lived the way our bodies and psyches are meant to live I seriously believe there would be fewer crimes and more freedom and less if any wars. Yeah I think it is that big of a deal. Look up polyandry (multiple husbands) on an internet search. It won’t be hard to find that polyandry was outlawed in 2300 BC.
    I found it surprising that in this article no mention was made of the Mosuo. (chapter 9). The fact of their over 1000 years of stability in “modern times” reveals Mr Hanson’s question in paragraph 7 to be suspect as just a staement of the party line rather than a quest for truth.
    He asked “The big question then is when did the biologically-rare (3% of mammals) phenomena of (near) monogamy arise in our lineage, millions of years ago with the rise of humans, or ten thousand years ago with the rise of farming?” Kind of like asking “Have you stopped beating your wife?”
    The question smacks of a forgone conclusion. In fact the book makes it clear that monogamy not only was not but still is not is not a natural condition. It is so unnatural that countless thousands have been murdered to enforce it upon us. I did not “arise in our linage” even to this day. It is not a part of our linage as linage is a biological process. Making such a statement is like saying “since when did our species change to enjoy government oppression?” Speak for yourself.
    It is truly telling that nearly all religions and all governments agree on enforcing monogamy upon the people. The government of Mao in China was as anti christian as can be and yet they violently did all they could to enforce monogamy upon the Mosuo in 1959 and onwards.
    The observations in this book at once condemn all modern religions yet also confirm the basic truths taught by nearly all.
    Personal freedom and the right to chose.
    Love and sharing all that is good with everyone.
    Rejecting all vestiges of ownership of humans by other humans.
    Every child being loved by every adult.
    But the author of this article persists in saying “Well we have it now so we now should accept it (monogamy) as the human condition.”
    Yeah well we have governments killing thousands and oppressing millions but I don’t accept it as a condition of being human.

    • farah

      It is truly telling that nearly all religions

      wrong most religions endorse polygamy.And who the fuck is being killed for not being monogamous ,are you mad.

    • farah

      It is truly telling that nearly all religions and all governments agree on enforcing monogamy upon the people.

      What the fuck most religions endorse polyagamy (isam,mormonism,buddism.)even christianity allowed polyagmy in the past .And most countries still alow polyagamy .My coultry allows polyagamy ,yet i do not no anyone who has such relationaship all members of my family are in llong term monogamous relatioships

      And can you show me where monogamy is enforced other than in marriage contract ,you simply can not marry more than one people but you can fuck ,date , who ever you want if you are married if your wive is on board with it and no one gives a rat ass.You are barging mad if you thing people ,especially in the west ,are oppressed with monogamy /You are free to date multiple people,have one night stands,remain single for life,marry and divorce every month if want,have orgies ,tresomes,go to any of the hundreds of swinging clubs all over the country …….and the government doesnt give a shit.but somehow you still think the government is oppressing you and if you are not monogamous you will be stoned to death.!!bohoo.

  • primate

    “.. A recent study … showed that more than half the young (seven of thirteen) had been fathered by males from outside the female’s home group.” [p70]

    This has been removed from the paperback edition because this study turned out to have been proved wrong a few years back – poor DNA analysis – and was retracted. Offspring are fathered within the community.

    Female chimpanzees are sometimes keen to mate because they experience general intimidation from males which makes refusal out of the question.

    Bonobo females exchange sex for access to food held by males. It is mostly the lower status females who are more receptive to sexual advances by males. Higher status female bonobos are able to refuse more male sexual advances.

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  • http://inbedwithmarriedwomen.blogspot.com in bed with married women

    See how everyone’s all hepped up and fightin’? That’s why I
    love this book. Thought-provoking, assumption challenging, fight
    inducing. Hooray!

  • https://twitter.com/robsica Rob
    • Irv

      Read the conclusion of that review, and it’s pretty weak. Ellsworth kindof shoots himself in the foot by saying “to be sure, I doubt that any serious evolutionary scientist, even the most ardent supporter of the ‘standard narrative,’ would argue that humans evolved in a milieu of perfectly monogamous pairbonds.”  So, in conclusion I guess he agrees with the authors, accusing them of biasing the evidence towards… the truth?!

      • ra6

         But its a disagreement as to how we are non-monogamous. His conclusion is that we are closer to harem building gorillas than polyamorous. It is also that since paternal certainty is valued in human culture, female promiscuity is sanctioned. Infidelity in females usually occurs only n in cases where it increases survival odds.

        His also refutes Ryan’s claim that we are egalitarian, and non-violent creatures

        Since Harem building leaves the majority of males without mates, it is more stable to have everyone be monogamous.

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  • http://www.facebook.com/john.o.mason John Oliver Mason

    I read the book, and it makes PLENTY of sense. I hope we can give up our sexual hangups, including monogamy, and realize there are no limits to how many people you love.

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  • Truth

    Basically monkeys and ooga booga people have matriarchies and patriarchy is what has given us advanced civilization.