Why you should be skeptical of evolutionary psychology

Using the attractiveness of waist-to-hip ratio as an example, psychologist and blogger Sabrina Golonka explains why you have to be skeptical when someone declares a psychological finding to be a universal human truth. It's not universal if it doesn't cross cultures. But we don't have great cross-cultural psychology data, and, where the data does exist, it suggests that things we assume must be true across cultures often are not.


  1. But the waist-to-hip ratio thing explains why Victorian women died out – their bustles made them too unattractive to mate with. Well, that and the bustles shoved their spleens into their necks. 

    1. There was no mass die off of Victorian women. Styles changed. They did faint and suffer from reflux due to the corsets, not bustles, pushed all their organs in and up. Smelling salts, ammonia in a crystal form, is what brought them back. The bustle did not actually touch the body and it did not put men off any more than silicon boobs do. The period was pretty hypocritical when it came to men and no one talked about anything that was even vaguely related to sex. Many people actually put stockings on tables so you could not see their legs. I have read lots of Victorian porn and it tends to be pretty silly and was for the consumption of men and whores. 

      1. There was no mass die off of Victorian women.

        Yeah, there was. It just happened after they had 18 children apiece.

  2. What I am trying to figure out is if the author finds fault with methodology, psychology as a science or the media’s coverage. Seems to me that the hypothesis that WHR may be a significant contribting factor in general attractiveness is a valid hypothesis. It may not be the only factor but from what I have read that does not seem to be the claim. To me it’s just another reason that being in the “soft” sciences sucks.

    1. I completely agree that this is a valid hypothesis.

      But, before anyone can make claims about an evolutionary basis we have to know  that, on average, 1) preference for low WHR translates into actual behaviour (ending up with a partner with low WHR), 2) having sex with women with low WHRs is more likely to lead to children than having sex with similar women with high WHRs. If these things aren’t true, then there needs to be some compelling case made for context-specific factors that might lead to a preference and advantage in one situation but not another.

      The reproductive advantage question is particularly difficult to address because we can’t run experiments on this kind of thing. Even using a correlational design it would be difficult to deal with issues like the increased prevalence of obesity today compared to thousands of years ago when any evolutionary preference might have been selected for (since obesity can have a large influence on fertility).

      So, I’m on board with doing the science to explore this issue, but I want it to be done well.

  3. This reminds me a bit of something someone (I think he was a behavioral economist) once told me.  It went something like, “we like to think we have a lot of data on how people do “X” (whatever X was…I forget).  But we don’t.  What we have is a lot of data for a particular subset of people, mainly American and European people.  And what we’re learning as we expand our scope is that not only is our data not very universally applicable to human beings in general, but it’s actually quite the outlier.  That is, we have a ton of data on people that are not only not representative of humans in general, but actually pretty darn weird and different compared to humanity as a whole and we must be very careful when trying to generalize our findings.”

  4. Why should you be skeptical of evolutionary psychology?

    Because you should be skeptical of EVERYTHING.

    “Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense.”

  5. Lack of universality is not a  disproof of evolutionary psychology, any more than lack of universality when it comes to lactose tolerance is disproof of evolutionary biology. Evolution produces variation within species. The question is what selection pressures produce any given feature, and are those pressures common to the whole species, or just a subset?

    1. Thank you. As mental health issues are now considered to be a matter of genes and gene expression, experiences as a child and teenager and experiences though adult hood it is would be surprising if everyone was the same. The permutations and combinations of things make it difficult to assess people in their own culture. I do not see how there can be any silver bullet. 
      The Dalai Lama was surprised when he first heard about mental illness in the west as he had not run into it before. His response was to study it, not dismiss it. He has worked with the medical community on it and many of the practices of Buddhism are now used in therapy: mindfulness, half smile, study… 
      There will likely be similar problems but will not have been caused by the same input and may not be aided by the same therapy. Culture is massively important in understanding individuals not just society as a whole. 

    2. You’re right, but Sabrina actually beat you to this argument; the post lays this out pretty clearly, and the point is the evidence for WHR being useful is actually deeply mixed.

    3. Agreed! I don’t have anything against evolutionary psychology as a strategy for answering questions about human behaviour. In this case, the media’s claim was that the WHR was universal while the data do not support this claim. Selection pressures can be highly context specific (as with the pressures that influence the production of lactase) and this presents itself as variation within the overall population.
      I think there probably could be a very good evolutionary story to tell about WHR, but it doesn’t seem like the research in this area is heading in a very promising direction. Although some researcher’s publish contradictory accounts of preference, others play down within-species variation and make assumptions about the link between hormone balance (related to WHR) and number of healthy offspring.

  6. My pet peeve – idiots who think that eye-contact (a very recent, very local fad) is some sort of universal indicator of anything at all.  It’s such a prevalent shibboleth that it’s even been written into diagnostic criteria.  Apart from being something that’s considered to be very rude in most cultures there are also little morphological patches (like say, the obscure group known as the “Chinese”) where  it’s physically impossible to do it because a lot of people have no “whites” to their eyes so you can’t tell where they’re looking.

    No surprise then that a recent study found “mysterious” levels of autism in Korean then is it?

    1. …there are also little morphological patches (like say, the obscure group known as the “Chinese”) where  it’s physically impossible to do it because a lot of people have no “whites” to their eyes so you can’t tell where they’re looking.

      I think you’re confusing “Asian people” with “sharks.”

      1. I think you’re confusing “Asian people” with “sharks.”

        The idea that Asian people don’t have visible whites to their eyes is bizarre.  Maybe he accidentally took a plane to Babylon 5.

        1. The idea that Asian people don’t have visible whites to their eyes is bizarre.

          I guess he just never bothered looking. We’ve already heard how little he cares for this new “eye contact” fad.

    2. Can’t say I completely disagree. It is not, however, a new “fad” to discuss eye contact. Thirty years ago, teachers-to-be in Canada, at least, were learning that Native American children were not being rude for not staring the teacher in the eyes. In their culture they were being polite. I have never ever had difficulty knowing if a Chinese person was looking at me. Of course, China has many different ethnic groups so maybe the several dozen people I have had as friends and work mates were different than your knowledge of the Chinese.

  7. This is a pet peeve of mine, a huge number of critiques of evolutionary psychology are actually critiques of shoddy science journalism. Even the term “psychologist’s fallacy” was coined before experimental psychology was invented, and introspection was all the rage. In the general sense we should be skeptical of all science, but the title of this post makes it seem that we should be particularly wary of EP. It then links to an article that holds a hypothesis up and presents evidence for and against. Conclusion, parts of the hypothesis are likely true but it’s not as simple as we first though. That’s pretty much how science works.

  8. I’m not sure you actually read the article, Maggie.  It’s far from an outright warning to be sceptical of EP (instead, mostly warning about taking popular media’s interpretation of EP seriously … and by popular media, I now have to include boingboing, apparently …):

    … rather than jump straight into a statement of universality, Singh says something a bit more measured. He claims “the fact that WHR conveys such significant information about the mate value of a woman suggests that men in all societies should favor women with a lower WHR over women with a higher WHR for mate selection or at least find such women sexually attractive.” That last bit is interesting. It merely suggests that men shouldn’t find women with low WHR unattractive. This is a very different argument than the oft repeated universal preference for low WHR. Unfortunately, Singh’s perfectly reasonable prediction has morphed into a presumption of universal preference for low WHR. This means that we hear little about evidence that contradicts this assumption. 

    I won’t quote any more, but the “we hear little about evidence that contradicts this assumption” still refers to the popular media, not the scientific literature, as the very next example is an EP paper from Westman & Marlowe (1999) which exactly brings that assumption into question.  Indeed, the article is full of links to EP articles which do the same.
    The point is that this is science in action. What the popular media latches on to is irrelevant. The fact is that, as Sabrina herself says:

    Reading these papers suggests a lively debate in the literature about the universality of low WHR preference.

    Which is exactly as it should be.
    C- on this one, I’m afraid.

    1. Agreed.  This article spends little time criticizing the psychologists in question, and mostly is (most correctly) skeptical of science media coverage.  In other words, what little ev psych actually says is interesting, but really the field has a long way to go before it can address “universal human truths”, and people *discussing* ev psych are prone to forgetting that.  Most of the actual scientists involved with it whose papers I have read are fully aware of this.

  9. So where did the human trait for well-developed female breasts come from? (I’m not disputing the premise of the article, I just want to know who I should address the thank-you card to.)

  10. EP as a subject is one of those genres that got totally ruined for me, intellectually, due to the amount of crap (especially sexist crap) flying that tag as a flag of convenience.

    To wit, take any of the 8,000 “articles” that “prove” that women don’t enjoy any kind of visual pornography, and that lighter skin/hair (reade: blonde) evolved as an attractiveness trait….meh.

    1. Just because some choose to abuse a framework of research doesn’t invalidate the entire framework: if homeopaths claim that quantum mechanics is somehow involved, it doesn’t leave me feeling that quantum mechanics has been ruined, merely that its invocation in an explanation needs to be examined and, probably, discarded.  Evolutionary psychology is, similarly, a useful framework, as is sociobiology.  Unfortunately, as its findings often lie too close to home for Homo sapiens for us to view with detachment (and can be, clearly, skewed by cultural biases), it makes it more important to treat it with a detached rigour that comes much more easily when dealing with less visceral topics such as, say, low-temperature superconductors.

      1. Yes, I think so too. The problem of being “too close to home…for us to view it with detachment” is a general problem for psychology. We all think we’re experts.

        This is why I think it’s so important to use the strongest possible methods to investigate claims that are fit so well with modern cultural norms. We mistake “what is now” with “what always has been.” In the WHR case, no modern, Western, reader is going to bat an eye at the idea that an hourglass figure is attractive. The concern is that this complacence filters into the science and we don’t scrutinize expected results that fit with the stereotypes as much as we scrutinize the surprising ones.

    2. Any good scientist knows that just because a finding is weird or even upsetting (seemingly sexist), does not render it false.  

      EP does not state that women do not ever enjoy any kind of visual pornography- it simply finds that they enjoy it, on average, less than men.  There is nothing sexist about that.  Women and men are not biologically the same. That doesn’t mean one is better than the other, it just means different, and you’d expect their minds to be different, too.

      It’s a shame that the media interprets EP’s findings to  seemingly legitimize them as some sort of ideal, but that is not the point of the field.  Simply because something is found to exist in nature, does not make it right.  (For example, it’s natural for men to rape and kill each other, but We don’t really let this one fly.)  For all the author’s whining about EP supporting the status quo in things like WHR, perhaps they would do better to start a campaign against popular media & advertising using exclusively thin, and unrealistically attractive models?  EP has actually proven that men prefer women to be larger than *they* think is attractive.  How’s that for sexist? What you find here, instead, is that media images distort these preferences into something non-representative of the normative population, and in many cases: unhealthy.

      Boycotting a field of science which has only shed light on the origins of some of these human behaviors and preferences should not bear the resistance.

    1. I don’t know, I think psychology that doesn’t use circular logic to prove that western cultural norms are universal would be a good place to start.

  11. The linked article references researcher Devendra Singh.  Dr. Singh was one of the greatest teachers I ever had, and a genuine inspiration.  God bless him.   

  12. Perhaps the headlines in media don’t popularize the cross-cultural research, but the leading psychologists who study WHR certainly do.  There is some cultural variability, yes, but over all, scientists have found this preference for low WHR in many cultures. That said, no, it’s not as simple as a .70 across the board, but that doesn’t mean the preference doesn’t exist: 

    “It is becoming increasingly clear that WHR assessment is more complex than an ‘invariant preference’ for a specific WHR such as .70.  Notably, the normal range of women’s WHR is higher in foraging societies than in Western populations and the average WHR of the most fertile females is higher in foraging societies.  Thus, when stimuli are use that more accurately characterize the local cultural range of WHR, men tend to find attractive a WHR that is LOWER THAN THE LOCAL AVERAGE.”

    That’s leading evolutionary psychologist David Buss from his book Evolutionary Psychology, The New Science of the Mind, 2008.

    What you find is that in cultures where there is food scarcity (and during difficult economic times), men prefer women who are heavier set, as it’s a good indicator of social status.  Whereas, in the US and other Western cultures where this is generally reversed, the opposite preference comes out.  That is, women can “afford” to be slimmer in these countries.  There’s solid evidence that these are context-dependent adaptations.

    (Sugiyama, 2005.  Physical attractiveness in adaptationist perspective.)

    WHR is a key indicator of long-term health status and women’s reproductive status.  Scientists acknowledge this- WHR a critical finding, not diminished by perfect cultural replications.  The contexts are important as well, but does not take away the value of such a finding.

    I’m bummed to see you publishing a headline that so poorly describes the article, and seeks to diminish the credibility of an entire field of study that has made so many tremendous contributions to scientific knowledge.

    1. I’m pretty sure I completely agree with you.

      I would add, though, that once we find mediating influences on preference (due to food scarcity or between group variability in mean WHR, etc.) then it’s time to change the reporting. Just like in statistics where we can’t interpret the main effects if you have a cross-over interaction, we have to stop interpreting an average preference if mediating factors reverse or eliminate the finding in particular contexts.

      1. I agree with you on your points about bad reporting- I’m not one that favors ill-worded articles on EP that seem to promote its findings as justification for women to try new weight loss plans, or try to look “ideal” for men… if anything, I find them repulsive.  (As you were lamenting your article).  Of course, this is hardly the point of evolutionary psychology itself, but can be chocked up to shoddy journalism.  

        And I agree, that it would be fair to mention this contextual factor in regards to WHR… but the preference for the low WHR is still not exactly exceptional- it strongly exists, regardless of the mediating factor of food scarcity.  (Even the BBC site has a WHR calculator, acknowledging that doctors are increasingly favoring this measurement over BMI for heart/obesity risk: http://www.bbc.co.uk/health/tools/hip_to_waist/hip_to_waist.shtml – and it’s not like those risks are culture specific.)

        In places where the .7 ratio failed to replicate, as you mentioned, such as in Tanzania and Peru, men still were found to favor a WHR that was lower than the local average.  To explain the failure of replication for the Tanzanians, Marlow et. al (2005) noted that the “results turned out differently when the stimuli included profile view of buttocks rather than the frontal views” (Buss, 2008).  They suggested that there was less disparity in the preferences of Tanzanians and American men than perhaps previously thought.

        Though body fat preference is definitely variable across cultures, the waist-to-hip shape has proven much more standard.  I would say with some of the historical evidence as well, the preference is quite possibly universal, even if the specific WHR of .7 is not always the same in every culture.   

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