Male preferences and debunking myths about the evolution of the female form

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Click for UncensoredIn the comments section to a 2blowhards post on booty shakin’, blogger Alias Clio puts forth an argument from incredulity regarding several hypotheses I proposed: 1) that male preferences for different parts of the female body have, over time, correlated with personality traits; 2) that natural selection has had a role in causing some men to prefer one body part over another; and 3) that the correlation could be caused by some simple mechanism. She also repeats an evolutionary just-so story about why human females developed large breasts — that is has something to do with face-to-face sex — and that too is worth taking a hard look at (the story, that is).

As to 1), the available data do paint a somewhat clear picture that assmen, boobmen, and legmen are not the same on average for personality traits. What Clio doubts is that the correlations here and now can be projected back into the past or into other parts of the world. That’s true enough, but it’s true of anything psychological, and only for technical reasons: when we discover which gene variants in males are implicated in preferring T over A, we can dig up or unfreeze ancient humans, sequence their DNA, and see if the males were boobmen or assmen. That’s how we found out that some Neanderthals were probably red-headed, despite the fossil evidence not telling us anything about their hair color.

Though everyone knows it’s a dubious move, the best we can do to see what preferences may have been like in sub-Saharan Africa 100,000 years ago is to investigate present-day hunter-gatherers in Africa. The Hadza are a well studied hunter-gatherer group who live in Tanzania, and a study by Marlowe et al. (2005) (free PDF) shows that Hadza males prefer females who have a low waist-to-hip ratio in profile (i.e. due to protruding buttocks), rather than from the front (i.e. an hourglass or wasp-waist shape), while Western males prefer the converse. The authors did not collect personality data on the Hadza males, and did not test to see whether a male preferred boobs or buttocks, but in principle this would not be difficult to do, and we could see whether a similar pattern showed up among African hunter-gatherers.

That brings us to 2), whether or not natural selection had a role in the emergence of boobmen. Clearly they are a new morph within homo sapiens. They are too high in frequency to be the result of de novo mutations here and now, and they did not all migrate from some pre-historic Martian colony of homo sapiens. That leaves genetic drift or natural selection. Genetic drift can cause allele frequencies to go up or down over time, but it cannot produce design. Mate preferences are too specific and coordinated during development to admit a believable drift explanation: natural selection appears to have fashioned them.

But toward what end? We don’t need to know, really. With the completion of the HapMap project, we are learning of tons of cases of natural selection in human beings, and we largely have no clue what it was up to. The numbers don’t lie. Still, let’s indulge in a little conjecture just to show that the idea isn’t so perplexing in the case of boobmen.

In many areas of life, there is no one best solution, and we face a trade-off. If I develop conspicuous ornaments, that may make me more attractive to females, but it may also give me away to predators more easily, or provoke the envy of duller looking males, who might ostracize me (no small matter in a social species). Duller looking males might avoid predators and envy-based ostracism, and may be able to work better in groups because of this, but they won’t be as attractive physically to females. The result is that some fraction of males will be dull and the rest conspicuous. We would need tools from game theory and differential equation modeling to spell out what parameters are involved, and what the exact frequency of each would be at equilibrium. But the point is that neither is universally favored, so both will co-exist.

So it could be with boobmen and assmen. I don’t think these preferences per se were the target of selection, but again that they correlate with other personality traits that have been under selection. For instance, everyone says that compared to boobmen, assmen are more likely to have polygynous tendencies, to prefer short-term relationships, and to emphasize female qualities most relevant to the short-term (such as her most sexual body part, the derriere). We don’t know if that’s true, but it would be surprising if everyone had the same specific delusion. Since both short-term and long-term strategies have pros and cons, both could co-exist.

If being a boobman is linked to a more monogamous orientation, we are asking how natural selection could have driven up the frequency of monogamous males in societies where boobmen are common, such as Northern Europe. Maybe agriculture there requires the father to stick around and provide for his kids, whereas in parts of sub-Saharan Africa where farming has lower energy requirements, females can farm on their own and not worry about whether the father will stay with her. I don’t claim that this is the only way it could have happened; this example is just to illustrate how simple the process can be.

Turning to 3), the mechanism does not have to be known in order to talk about the adaptive value of the trait (see Niko Tinbergen’s Four Why’s for clarification). We know that lighter eyes were selected for in Europeans, but we could know this fact even if we didn’t know what biochemical pathways are involved in eye color. Still, let’s indulge in a little more conjecture just to show how non-mysterious the mechanism can be. It may be as simple as testosterone level, with assmen having higher T than boobmen.

This is an incredibly easy hypothesis to study empirically, though from Googling it looks like no one has done so. To repeat a finding from the boobman, assman, and legman study, though, the assmen and those who prefer both large breasts and large buttocks have more ambitious personalities and are Type-A businessmen. We also know that in various species, such as the dark-eyed Junco, higher testosterone makes a male more polygynous and less likely to stick around to help raise the kids. Whatever the mechanism turns out to be, investigating the matter is not so perplexing that we don’t even know where to start looking.

Last, let’s examine some very popular but utterly ridiculous hypotheses for why human females evolved large breasts, summarized here. First of all, it is not true that human females have large breasts — some have small, some medium, and some large. Look at the picture of the chimp in that summary — you see human females with breasts that small (or large) all the time. This is not hairsplitting: it suggests that breast size reflects some trade-off.

For example, the trade-off could be in fat deposition: if you have a fixed amount of fat and want to be conspicuous, you had better put the bulk of it in one place or the other. Only gifted (or cursed) females have so much to go around that they can have large breasts and large asses. Those who put it in their chests are probably pursuing a long-term mating strategy, and those who put it in their behinds are probably pursuing a short-term strategy, on the assumption that female supply has evolved to meet male demand.

The evolution of breasts has nothing to do with mimicry of the buttocks — can you think of any other way that a man might view buttocks-resembling things on a woman if he wanted to? Moreover, do assmen respond at all similarly to boobs as to the buttocks? This hypothesis predicts that they should be roughly interchangeable, but I don’t even notice who has big or small boobs unless someone points it out to me, and I have no way of judging what “good boobs” look like, according to boobmen. It also has nothing to do with our species’ face-to-face sexual position — again, can you think of any other way a man might look at buttocks-resembling things while having sex? And as misleading as the name may be, doggy-style is not a trait that humans have lost, like a coat of body fur.

Neither does it have to do with our bipedal posture: it’s true that this posture would have obscured any rump swellings (as chimps have), but the fleshy buttocks have still been in plain view ever since — and typically, more viewable from afar than the breasts, as they take up more volume. Five-hundred years from now, the scientific consensus will be that invoking bipedal posture as a driver of some clearly unrelated change was the 20th century equivalent of ancient Greek theories about trepidation of the spheres.

Since such hypotheses are so easily debunked, why have they persisted for as long as they have? Napoleon said that you should never attribute to malice that which can be explained by incompetence, and here the incompetence surely stems from the majority of researchers and commentators in this area being boobmen, legmen, or women. (Women will grudgingly admit that boobs and legs can be things of beauty, but recoil in disgust upon pondering the booty.) We all have a tendency to extrapolate from the personal to the universal, but when I find out that someone thinks or behaves differently than I do, I ask what forces could cause them to think or behave in such deviant ways. That’s how you get a clearer picture of how the world works, but it relies on there being a diversity of views within the field. It’s about time some assmen joined the ranks of sex researchers to set the field straight.

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42 Comments

  1. Tell me about the leg men.

  2. i’m with luke. a bivalent discourse is fundamentally marginalizing the Other.

  3. The different fundamental forces are partly distinguished by their different effects at different distances. I would suggest that the buttocks are like gravity–quite attractive at great distances. Breasts, like nuclear forces, are extremely powerful at near distances. (*Quite* unlike the buttocks, I might add.) 
     
    It depends upon what effect is desired. A woman who wants to attract far and wide will use her rear. A woman who wants to attract close and strong uses her breasts.

  4. Ha, Razib you Bowdlerizing Victorian. 
     
    Re: legmen, here is the gist from the Wiggins et al (1968) study: 
     
    The most substantial correlate of large-leg preference is an abstinence from alcoholic beverages as indicated by the negative correlation with both drinking and amount of drinking. Those who preferred large legs are nonaggressive and self-abasing (guilty, self-blaming). They tend to be psychologically minded (intraceptive) and are characterized by a slow personal tempo. . . Subjects who preferred large legs indicated that they are not business majors and that they would choose their mother over their father if they had to make a choice. The personality pattern suggested by these correlates is one of inhibition and restraint in social situations. 
     
    I would suggest that the buttocks are like gravity–quite attractive at great distances. Breasts, like nuclear forces, are extremely powerful at near distances. (*Quite* unlike the buttocks, I might add.) 
     
    No assman would say that, and who do you think has more trouble keeping his hands off of his preferred body part at close distances in a dance club, let’s say? So again we see how the Blinkered Boobman Bias muddies our clarity. A nice ass is even more attractive up close, where its presence is palpable. But if we use “distance” metaphorically — like the ass girl casts a wider net than the boob girl in attracting men — that’s my hunch too.

  5. large-leg preference 
     
    it isn’t size, it’s shape & length. how do they quantify this in the paper?

  6. Could you support your claim about the composition of researchers?

  7. Ha, Razib you Bowdlerizing Victorian. 
     
     
    sir, 
     
    i object to your implied use of the term “Victorian” as one which might cast aspersion! 
     
    sincereley, 
    c.v. snicker

  8. No assman would say that, and who do you think has more trouble keeping his hands off of his preferred body part at close distances in a dance club, let’s say? 
     
    That’s because grabbing ass and grabbing boobs are at different levels of intimacy. Hands on boobs is foreplay and you can’t go straight to it. Hands on ass can be just flirtatious.

  9. Hands on boobs is foreplay and you can’t go straight to it. Hands on ass can be just flirtatious. 
     
    wait, are you really italian or something?

  10. I never bend over when I am near a known assman, but boobmen are much more trustworthy.

  11. What about face men?

  12. it isn’t size, it’s shape & length. how do they quantify this in the paper? 
     
    They had silhouette drawings, and the larger legs were longer and a bit wider (but I believe the proportion was kept the same, just blown up). 
     
    What about face men? 
     
    Every man pays attention to the face, enjoys a pretty face, and can agree on what a pretty face is like. It’s only when you ask guys about other body parts that individual variation becomes apparent.

  13. wait, are you really italian or something? 
     
    Italians… 
     
    http://www.youtube.com/watch?v=vbEz9FXtclM

  14. Have you even thought how are those traits good for women and birthgiving/childcaring?  
     
    I mean: one problem human females have is that birthgiving and bidepedalism are largely in conflict. For bidepedalism the ideal shape would be the male one, with narrow hips, for birthgiving is ideal to have rather wide hips.  
     
    So female specific morphology in this aspect is largely conditioned by these two contradictory needs. Too narrow waist and birthgiving can be dangerous, too wide and mobility is limited.  
     
    From the viewpoint of men, if you prefer an “action woman”, you surely do not want her with too broad buttocks, if what you want is primarily a mother, then the opposite may be true.  
     
    The breasts instead seem secondary, right? There doesn’t seem to be any real need for large breasts other than erotic publicity. Most mammals, including our closest relatives, manage with much smaller ones without any problem. 
     
    Anyhow, I am of the impression that men (and women) normally like better what they are used to. In PNG they like women with big noses, for instance. Of course you can argue that the opposite is true instead: that such traits have evolved because of sexual selection. But I’d rather think that drift has caused individual and ethnical preferences, at least to some extent.

  15. What about people who fit more than one of these categories? 
     
    Say… someone who is both a boobman and an assman. 
     
    – Charles Iliya Krempeaux

  16. Agnostic, I do wish you’d stop coming up with spurious reflections about why women think this or that about these issues.  
     
    I couldn’t care less whether a man prefers bosoms to buttocks, have no special squeamishness about the subject, and have reason to be grateful for the existence of the latter preference, since my own body type is more JLo than Sophia Loren. Just to show you how it feels to have these irrelevant motives imputed to your comments, I will put it to you that the reason you are attached to the hypothesis that “ass men” are high in testosterone, and “boob men” are betas, is that it confirms your uncertain hope that you, with your much-trumpeted preference for female posteriors, are yourself a high-testosterone alpha.  
     
    Your post is a series of evasions of the points I made in my original comment. I will have to think carefully to prepare my response, so that I can make my questions clear, which may take a couple of days. You may well have a plausible answer for them, and I’ll be interested to hear it. Meanwhile, I want you to understand that I made those points out of a real curiosity about the subject, and am not dogmatically attached to them.  
     
    My curiosity and questions remain unsatisfied by your discussion – or should I call it a dismissal? – of my comments.

  17. I will put it to you that the reason you are attached to the hypothesis that “ass men” are high in testosterone, and “boob men” are betas, is that it confirms your uncertain hope that you, with your much-trumpeted preference for female posteriors, are yourself a high-testosterone alpha.  
     
    Ha ha, guy got pwned… by a girl

  18. aawww.. Razib, you have to go down to this topic to enliven your website? Subjecting women to being objectified based on their body parts? Shame on you.

  19. aawww.. Razib, you have to go down to this topic to enliven your website? Subjecting women to being objectified based on their body parts? Shame on you. 
     
    LOL. contrary to what you might imagine, i don’t have half a dozen handles with which i use to post on this weblog. the person who posted this entry is not razib. you might have noted the “posted by agnostic” next to the title; that’s not there for stylistic effect. 
     
    and assman can post on what he wants.

  20. Ha, nice try Clio, but digit ratios don’t lie. Mine is above-average even for those who are abnormally flooded with testosterone in the womb, and I have a good track-record of being competitive in real life. 
     
    I’m not here for impression management — I could care less what the internet thinks of me, since it cannot profit me in any way — but to publicize data that bear on questions that people normally bandy about without proof, and to clear up fuzzy-headed reasoning. 
     
    I only mention personal biases when it’s clear that the argument is wrong — like, why didn’t they notice? Personal biases don’t matter per se: they could allow a person to see things others don’t, assuming they’re right. 
     
    You repeatedly said “I can’t imagine why…” or “I don’t see why…” in that thread, as though that were a genuine objection. And you parroted the “breasts and face-to-face sex” story without thinking about it. I wasn’t trying to pick on you in particular, since just about everyone in the literature (peer reviewed or in popular form) does the same thing. Your comments were just what motivated me to write this up.

  21. What about people who fit more than one of these categories? 
     
    Say… someone who is both a boobman and an assman.
     
     
    From the review linked to under “correlated with personality traits” in the first paragraph: 
     
    Men who preferred the “large” figure — large breasts, large butt, and large legs — were characterized by “a need for achievement.”

  22. Agnostic, man, you don’t like the motor-boat?

  23. the reason you are attached to the hypothesis that “ass men” are high in testosterone 
     
    Ah, now you’re just lying — if I were so attached to my hypotheses, I wouldn’t use the phrase “indulging in conjecture,” twice, would I? It’s pretty clear that the post is meant as an exercise to show how simple the steps may be, a qualifier I used repeatedly, and that none of it need be mysterious. 
     
    Don’t take these things so seriously.

  24. Could you support your claim about the composition of researchers? 
     
    Not to sound too much like an assman-supremacist, but if assmen do indeed have higher testosterone we won’t have much patience for or interest in that kind of research, or in studying the social sciences in the first place. 
     
    To provide one data point, I know I don’t. I did some engineering/meteorological research for my thesis and it cured me of ever wanting to touch any research again. The only research I’ve found at all appealing involved blowing stuff up.

  25. Ha, nice try Clio, but digit ratios don’t lie. 
     
    About what? Apparently Finnish men have the most extreme digit ratios in the world. Are Finns extraordinarily likely to be high testosterone alphas? 
     
    Mine is above-average even for those who are abnormally flooded with testosterone in the womb, and I have a good track-record of being competitive in real life. 
     
    Competitiveness can be a “masculine” trait in the same sense that high math ability is a “masculine” trait. Ultra nerds are ultra competitive – it’s just that they end up competing in WoW levels and the like. “Masculine” digit ratios in fact have a known relation to autism. 
     
    I’m not here for impression management — I could care less what the internet thinks of me, since it cannot profit me in any way — but to publicize data that bear on questions that people normally bandy about without proof, and to clear up fuzzy-headed reasoning. 
     
    You’re still conspicuously interested in simultaneously pointing out that you’re an assman and that your digit ratio is “above average” and… 
     
    It all really sounds like you’re trying to convince yourself of something. Did this all start when you discovered the PUAs and their silly obsession with “alphaness”?

  26. Jaakkeli, it’s no wonder that Finns have never exported anything of worth to the world: none of you can think very clearly. 
     
    Are Finns extraordinarily likely to be high testosterone alphas? 
     
    You’re confusing individual with group differences. 
     
    Competitiveness can be a “masculine” trait in the same sense that high math ability is a “masculine” trait. 
     
    Yes, I believe one definition of “masculine” is “more characteristic of males.” If you mean that they are more characteristic of alpha males, then you’re wrong: only competitiveness, not high math ability, is masculine. 
     
    You’re still conspicuously interested in simultaneously pointing out that you’re an assman and that your digit ratio is “above average” and… 
     
    I point out that I’m an assman as a gag — as everyone except you has already figured out. I am not at all interested in pointing out my digit ratio — only did so, once, to prove that Clio was wrong. 
     
    I am, however, narcissistic and mildly sociopathic — but then, all great people are. Hell, I’ve contributed more to our understanding of the world just in my posts here and at my personal blog than you will in your lifetime — not because they are genius posts, not at all, but because you, like most people, are an incurious idiot. 
     
    Did this all start when you discovered the PUAs and their silly obsession with “alphaness”? 
     
    Ha, yes, I only figured out that I was an assman, and that I have a high drive, a few months ago. The concept of alphaness is well established in biology, including humans. Feel free to read the talk in the post above: exceptional males have been rewarded throughout history, while most males have been genetic dead-ends. 
     
    BTW, this is the last comment I’m allowing for now in this direction. I don’t mind letting the retards run loose later on, but early comments must stay somewhat on the topic of the post.

  27. mildly sociopathic - 
     
    understatement???

  28. Hey now, let’s not restrict the range of the comparison class. 
     
    You wanna see a more serious sociopath? Lemme show yo’ ass somethin’… 
     
    http://www.youtube.com/watch?v=Ue-rVWFadEQ

  29. i think that’s more psycho than socio….

  30. 1) The study you point to was based on self-reporting. It measured what guys thought they like, or what they think they’re supposed to like. This may or may not be correlated with their actual instincts when faced with the Real Deal. 
     
    2) In your appraisal of the Assman, you bizarrely overlook certain details of the study, namely the fact that assmen are supposed to be “dependent and given to self-abasement (guilty, self-blaming)”; that ass-preference correlates positively with the traits of “order” and negatively with “autonomy”; and also negatively with “intraception”.  
     
    So basically, the assman is not the Alpha-Male; rather, he’s the quintessential fascist, scoring high on “authoritative” traits. Think Eichmann, not Superman. 
     
    On top of that, I note that only boob-men correlate positively with the traits described as “exhibition” and (shudder) “heterosexuality”. No wonder Nazis were so often gay – they were probably all ass-men! ;) After all, it stands to reason that strong heterosexuals would focus on that part of the female anatomy that is absent in men, no? 
     
    More seriously, maybe “breast-preference” simply detected the frat-boy who thought he’d have a laugh and consistently report preference for big-breasted figures: you’ll note that the Lara Croft-like pictures used in the study make breasts much more prominent than buttocks.  
     
    However, one interesting point is that “butt-preference” doesn’t correlate with much at all. By contrast, small/big boob-preference is correlated with many different traits (see Table 4). So the punchline of your quest for the specific traits of the assman might be precisely that there is no such thing as an “assman”! 
     
    [General disclaimer: anyone who takes any of the above too seriously might have missed the point of the post.]

  31. Despite not being from the Kalahari Desert, I’m a “bushman.”

  32. “Don’t take these things so seriously.” 
     
    I didn’t.  
     
    And I don’t feel picked on, either.  
     
    As for not benefitting by anything you say on the internet, that’s irrelevant to the issue, which is, does being an “ass man” lead you to want to believe that “ass men” are more virile? That’s the kind of self-image a man might wish to confirm to himself quite independently of what other people think of it.  
     
    And I do NOT take the hypothesis about breasts being a substitute for buttocks seriously. I think it’s absurd. But I also think your counter-arguments are a bit goofy.  
     
    As I said, I am planning to try to draft my questions in a clearer form so that you can, perhaps, give me a more sensible answer to them. I don’t doubt that you know more than I do about this subject, but your last response really missed the main issues. No doubt that’s because my original comments at the Blowhards’ site were written in a jocular fashion.

  33. when we discover which gene variants in males are implicated in preferring T over A 
     
    You haven’t even established that this preference is genetic before jumping to this. It seems quite likely that it is, but as far as I can tell the nurture hypothesis for this psychological variation hasn’t been addressed yet. Plus as far as I can tell you’re hanging a lot of this on a single, kind of dated-seeming study (the dated part being the psychological modeling) from fifty years ago.  
     
    I could care less what the internet thinks of me 
     
    Hence the seven replies in the comments from you. You want to see someone who really doesn’t give a damn what his commenters have to say, check out Yglesias.

  34. It’s pointless to debate what traits truly are and are not “alpha-male” traits — terminology.  
     
    rather, he’s the quintessential fascist, scoring high on “authoritative” traits. Think Eichmann, not Superman.
     
     
    Something like that — I used the phrase Type-A businessman or political leader in the lit review. He’s a builder of civilization, hence the concern with people getting out of order. 
     
    the issue, which is, does being an “ass man” lead you to want to believe that “ass men” are more virile? 
     
    The central issue is not “does something about the person X lead them to believe Y?” (Just to stir things up — why are women always so obsessed with this question? Rina in New York was like that too.) It is, “is person X correct about Y?” 
     
    It’s interesting on a sociological level, but not regarding the merits of their belief. If X is astoundingly wrong about Y, maybe we look to the person to see why they could hold such wrong beliefs. 
     
    You haven’t even established that this preference is genetic before jumping to this. 
     
    I haven’t established a lot. The post is an outline of how things could work. The Wiggins et al study is dated in the sense of not having follow-up studies, but they had a decent sample size and their results were statistically significant. That’s more worth believing than anecdotes. 
     
    Hence the seven replies in the comments from you. 
     
    They were mostly in response to questions people had about the substance of the post, and the others are to discourage comments that are too off-topic early on.

  35. … the hypothesis that “ass men” are high in testosterone, and “boob men” are betas…  
     
    They don’t have to be incompatible but, if these categories do exist, I’d rather think ass-men are looking for reproduction and boob-men for sex, even if unconsciously. Hips are more likely to correlate directly with child-birth, while boobs rather seem a sexual semaphore. 
     
    Human females are the only great ape with such large breasts. Chimps and bonobos instead have large genitals, also as sexual bait. Gorillas and orangutans, that are not just more distant but also poligynic, lack of such sexual attributes – the main dimorphism being body size and secondary attributes of males (to attract as many females as possible to their harem, I guess).  
     
    So we are more in line with Pan sp. Chimp males also have visible sexual attributes in their genitals with the largest testicles among all apes. Human males instead have the largest penises in the family (chimps are intermediate, gorillas and orangutans have it small). 
     
    But I think that sexual selection is not just about that. Overall physical and psychological evaluation happens too, at least when the issue is somewhat serious. Chatting and dancing are just two sooo typical ways of getting to know each other – though surely women are more attentive to this kind of less obvious clues, at least on average. Personally I find the face (and eyes) extremely important in judging and feeling attracted to (or repelled by) people (not just in the sexual sense but also) – and I don’t think I’m so special. A nice body helps of course… but it’s not just about boobs and asses.

  36. On a lighter note, it seems that Indians are Boobmen, or at least Nipplemen, if this Bollywood video [NSFW] is to be believed?!

  37. Indians, motor-boatin son-of-a-bitches all of them. A bunch of old sailors!

  38. Luis — to clarify, assmen pay attention to how the buttocks protrude from the body, not necessarily to the breadth of the hips. To repeat a finding from the Hadza study, the males prefer somewhat narrow hips but protruding buttocks. So the connection between a focus on the derriere and on wide hips for birthing isn’t automatic.

  39. That Berlusconi video is apparently, tragically, a fake.

  40. Luis — to clarify, assmen pay attention to how the buttocks protrude from the body, not necessarily to the breadth of the hips. To repeat a finding from the Hadza study, the males prefer somewhat narrow hips but protruding buttocks. So the connection between a focus on the derriere and on wide hips for birthing isn’t automatic. 
     
    Ok, noted. You are hence suggesting that buttock size in women is also an erotic-appeal specific traic, like boobs, right?

  41. Right.

  42. Ha, nice try Clio, but digit ratios don’t lie. 
     
    Inter-individual psychological correlates of digit ratio are low: 
     
    All the associations with RFL mentioned above are pretty slight (Manning does not give correlations but his occasional scattergrams indicate effect sizes of around .25).

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