Sex & sport

By Razib Khan | June 23, 2012 10:26 pm

The New York Times has an article up on a new I.O.C. ruling on who can compete as a woman. Basically they look at testosterone levels. This seems a different tack than cases where women were banned from competing as women because they had a male karytoptype (AIS). This article came on my radar because I had already read this op-ed from about a week ago, You Say You’re a Woman? That Should Be Enough. This sentence jumped out at me:

Second, when it comes to sex, sports authorities should acknowledge that while science can offer evidence, it cannot dictate what evidence we should use. Scientifically, there is no clear or objective way to draw a bright line between male and female.

What do people think of this assertion? I’m aware of intersex individuals. But if we start to assert that dioecy is just a “social construct” then let’s revisit species concepts. I’m sure there are some farmers and loggers who might assert that one can’t draw objective bright lines between populations. Distinctions between male and female in most species is much more clear and distinct than various taxonomic categories.


Comments (20)

  1. Darkseid

    maybe they’re being obtuse and insinuating about all of the different XYY, XXY, XXX, XXYY rare combos people can be born with. One of the authors is in Women’s Studies – I have a friend taking a Women’s Studies class and the “facts” they’re learning are stunningly wrong and politically correct. he was literally removed from class for questioning the teacher and not just accepting what they were being fed.

  2. Chris Ho-Stuart

    Here are a couple of cases which seem to defy easy classification.

    A “chimera”. This is a person who has cells derived from two zygotes. It can happen if two fertilized eggs merge very early in development. The individual may appear entirely normal (there may be chimeras reading this who are unaware of their condition); but the cells in their body will come from two quite distinct origins. If the original zygotes were male and female, then the adult individual will have some cells in their body with the XY (male) chromosomes, and others with the XX (female) chromosomes. There may be no external sexual ambiguity as long as the sex organs all come from the one lineage; in general all kinds of sexual ambiguity might arise.

    Second case; more common (though still unusual) is where an individual is genetically of one gender, and phenotypically of the other. This can be either an XX individual who develops with external male genitalia; or XY who develops with female genitalia. This is usually caused (I think) by excess or deficit of the appropriate hormones during fetal development.

    For most people, gender is unambiguous. But there is no sharp dividing line or easy way of classifying that covers all individuals.

    The examples I’m considering are entirely independent of psychology or choice. They are real physical conditions in which the conventional physical basis for determining gender becomes ambiguous.

  3. It is much more difficult than you would expect. There are XX individuals with male genitalia and XY individuals with female sexual characteristics. Do you define a “woman” as someone with the genetic profile of a woman, the external characteristics of a woman, the metabolome of a woman, or someone that feels like she is a woman?

  4. John

    I’m not a scientist or anything, but wouldn’t the differences in endocrine systems be a pretty large and objective way to draw between the sexes? Or am I just talking out of my ass?

  5. Peter Ellis

    While dioecy is not a social construct, the Olympics are – so at some point there has to be a mapping between physiological reality and the social context.

    I don’t think they’re being quite as obtuse as to say there is no such thing as maleness or femaleness. Rather, the point is that maleness/femaleness consist of constellations of features, some of which affect athletic prowess (stature, muscle mass), some of which do not (happening to have ovaries or testes). Some are testable, some are not, and so on. If you want gender-segregated sports, which factors should you use to define gender?

    It’s all very well saying that the difference is usually clear – the whole point is what to do when it isn’t. Intersex is the most profound problem, but not the only one: consider females abusing anabolic steroids – they may well only be raising their testosterone levels into the normal male range. How do you define that normal, how do you test for it, when should you be suspicious that foul play is involved?

    And yes, species concepts are much more fuzzy in many cases. Were mice to hold their own Olympics, they might well have learned (if slightly furry) discussions about whether musculus/domesticus/castaneus should compete in the same events, and if so, which events molossinus or other hybrid individuals should compete in. As humans, we dodge that bullet by having no closely enough related species to confuse the issue. The difference between us and a chimp is well defined. If Neanderthals were still around, that would be a different matter.

  6. Syon

    Bruce Kidd: “If the proclaimed human right of self-expression is to mean anything, surely it should protect the right to name one’s own gender,” he says.”

    “We agree. At present, though, because most nations do not offer their citizens the right of self-defining gender, the best bet might be to let all legally recognized women compete. Period.”

    Well, that is about the most full-on expression of sheer blank slatism that I’ve come across in some time.

    It also sums up why I am a conservative. Leftists see no barriers, no constraints upon humanity (well, except when it serves a political purpose, cf the dominant line on homosexuality being “innate.”). Everything is a matter of social construction, of chosen definitions. I am a conservative because I recognize the limits that reality imposes on our choices.

  7. jb

    I missed the op-ed by Jordan-Young and Karkazis , but all I can say now is wow! I happen to agree with them that testosterone levels are not the best way to determine who should be allowed compete as a woman, but they take that reasonable point and use it as a springboard into pure ideologically motivated delusion.

    I was particularly amused when they said “Sex segregation is probably a good idea in some sports, at some levels and at some moments.” I would love to see their enumeration of sports, levels, and moments when it is not a good idea!

  8. I think sex is much more clearly defined than species, by the nature of sexual reproduction alone. I suppose things get super-complicated when you think about humans and intersex individuals, etc.. And just because I believe sex to be relatively clearly defined doesn’t mean that there’s a socially nice way to draw lines.

    But the author above stated “scientifically, there’s no… way to draw a bright line between male and female”, which isn’t true: there’s the biological way to define male and female. Males produce male gametes and females produce female gametes, that’s it. Rather cut and dry in comparison to the species problem.

  9. Scientifically, there is no clear or objective way to draw a bright line between male and female.

    If we’re talking scientifically (in terms of chromosomes and phenotypes), then the above statement would be true for less than a tenth of a percent of the population, according to Wikipedia. In which case, this whole argument is really best left to the tiny community of truly intersexed individuals. Insofar as an intersexed individual wants to compete in a traditionally male/female sport, then it’s up to the ruling body of that sport to decide. I don’t see the controversy here, just another Leftist journalist trying to drum some up.

  10. #2 and #3, i referred to intersexed ppl in my post. i also linked to an ASI XY person. no shit there are exceptions. there are fertile tiger-lion hybrids too. species distinction, so tricky there!

  11. Randall

    It looks like a preposterous statement that rejects facts in the service of leftwing ideology. They have an outcome they want: getting women into mens’ sports and vice versa. This outcome will serve various leftwing agendas. They need a rationale for it. The rationale, in this case, is based on an attempt to use rare exceptions to undermine the discrete categories male and female.

  12. Chris

    Kudos Peter Ellis for summing things up so clearly! The IOC exists to create as ‘fair’ a playing field as possible for the Olympics. Ideally all competitors would have the same genetic characteristics so only one’s dedication to training would determine their placing in events. Obviously this is impossible with the amount of variation within our species. One circumscription, the separation of ‘men’ and ‘women’ into separate competitions, has eliminated much of the rabble surrounding ‘natural advantage. Statistically there is a difference in the mean strength, height, and stamina in (self identified) men vs women. There can be considerable overlap however, as in the case of some intersex individuals or for example a female-to-male trans person who isn’t on testosterone.

    Given these goals and limitations I feel the switch to testosterone levels would be a great way to create a fairer competition. Better would be to remove the gendered labels from these groups. Best would be multiple tears of hormone level classes combined with weight and height classes depending on how much they influence the outcome of the event. Similar ideas can be found in boxing with weight classes.

  13. Peter Ellis

    Testosterone levels is almost the worst option – a huge proportion of intersex cases stem from androgen insensitivity. The amount of testosterone’s irrelevant if there’s reduced receptor function.

  14. Chris Ho-Stuart

    I appreciate that Razib did mention intersex in his post; I gave a couple of concrete examples. I didn’t mean to imply you were unaware of them, Razib. But I still thought it worth describing those concrete details as an example of where ambiguity arises as a simple physical fact. It seems to me that you can’t say the distinction is unambiguous by allowing and removing from consideration the ambiguous cases.

    I think that for humans, you can give a clear male/female distinction for individuals by looking at what gametes are produced; the problem is that this distinction is not one that matters for sports. It’s all the other associated paraphernalia.

    I find it a little weird to see this cast as a leftist or rightist position. People of any particular political leaning are capable of ignoring or distorting plain empirical science for irrational reasons.

    But isn’t it a measurable basic item of data that the various aspects of gender that impact upon sports don’t have sharp dividing lines? Isn’t that data that all political leanings need to consider and take into account as a factor for deciding policy?

  15. #14, as i said in the follow up post i don’t care about the sports issue that much. rather, i’m highlighting the general point that the cultural left has discomfort with sex differences, and takes a stance of hyper-skepticism to any positive assertion of difference. why does this matter? because my liberal friends keep telling me that the cultural left has made peace with sociobiology, and the ‘blank slate’ is a straw-man. but the reality is that a substantial number on the cultural left still take a maximalist social constructivist view, which is most easily discernible in the most robust suite o bio-behavioral differences which exist in our species, that between men and women.

    now, you might say that i shouldn’t politicize this. but i will,because scientists feel free to rightly attack social conservatives who reject evolution as idiots, and generally smear the political right as a whole. i’m not totally comfortable with this line of attack, but it’s legit.

  16. Chris Ho-Stuart

    My apologies Razib; I guess I missed most of that. The political/cultural stuff is not that much of my interest; and I’m not even entirely sure of the specifics of your concern. The distinctions between gender seem to me to be more clear that the distinctions between political stances; what it means to be liberal/left/whatever is harder (IMO) to nail down than what it means to be male or female. Which I think you might agree with as well…

    I personally think the exceptional extent of scientific disfunction within the political right in the USA is probably something of an extreme and an anomaly on the global stage; I don’t know why.

    Cheers — Chris

  17. I am not going to defend gender self-identification in sports, but the bolded part of what you quote is certainly true. It does NOT however amount to asserting that dioecy is just a “social construct”. Perhaps that silliness is elsewhere in the article but I don’t see why the ‘no bright line’ bit struck you so strongly when you clearly seem to agree with it. (I am reading ‘bright’ as ‘sharp’ and interpreting the claim as just saying that there is no agreed partition of the set of all humans into exactly two sexes.)

  18. In all but a very tiny minority of sports (e.g. those where being small imparts acrobatic abilities like diving and gymastics due to cube-square scaling laws), men, on average, perform better than women in absolute terms (which is one reason, although not the only one, why there are separate men’s and women’s categories) due to greater strength/siz. (I have no idea if there are systemic differences between male and female performance in sports like target shooting that don’t obviously have gross physiological differences as an important component.)

    That means that top men’s competitors are typically going to be in no manner gender ambiguous, but that the extreme outlier individuals who are Olympic athletes on the women’s side are going to be on the extreme male side of the female-male trait distribution in at least some respects (e.g., size, muscularity, body fat, aggression) perhaps due to atypical underlying genetics or physiology. Olympic athletes are almost by definition physiologially outliers.

    Thus, clarity about how one defines the sex of an athelete for women’s Olympic class sports matters much more than clarity about how one defines the sex of an athlete for men’s Olypmic class sports. Olympic’s women’s sports that do not have “inverted” absolute success measures are a natural attractor of ambiguously sexed individuals.

    Of course, in order to get the right definition for this purpose you need to know the purpose for the classification. Why exactly do we care if a female Olympic athlete is a female rather than a male?

    When you are dealing with ordinary womens v. mens sports, where outlier individuals who are gender ambiguous are vanishingly rare, the need for rough equality between competitors on a variety of measures to make it interesting and to allow women to participate with an appropriate handicap is obvious and any distinction you use is going to produce the same results down to 0-1 ambiguous individuals who by themselves won’t unduly skew either pool, particular if the ambiguously sexed individual in that community doesn’t personally have exceptional athletic ability anyway. If the only sexually ambiguous individual in your community is a couch potato, accurately classifying that person matters even less.

    But, at the elite competition level in women’s athletics, outcomes may be driven quite a bit by definitions and the need for clarity of vision about why we have men’s v. women’s sports becomes much more important. The case of an XX v. XY, v. Testosterone level, v. Pensis v. No penis, v. cognitive identity test becomes really muddy. The argument for a hormone based test seems to focus on the fair handicap system justification, but it isn’t really obvious that this justification is coherent at the level of Olympic elite performers.

    There is also a case that one ought to define athlete sex for the purposes of e.g. individual supports that measure raw physical ability, differently than e.g. in team sports or “combat” sports (e.g. marital arts), where cognitive aspects of gender differences are arguably relevant in addition to physiological differences.

  19. Doug1111


    For most people, gender is unambiguous. But there is no sharp dividing line or easy way of classifying that covers all individuals.

    It’s not most people. It’s virtually everyone. The percentage of intersex people is miniscule. Though when they wish to compete in sport on the female side (as they always will – it’s much less tough competition), they will tend to rise to the top and hence to wide attention.

  20. Chris Ho-Stuart

    Doug1111; of course. The two examples I described are extremes; which are worth looking at (IMO) mainly because it shows plainly that difficulties are not simply social constructs but real physical issues.

    More common than the examples I described are cases in which an individual is genetically male or female, but because of insensitivity to sex related hormones, develops gender characteristics inconsistent with their genetic gender.

    For example, “Androgen insensitivity syndrome”, which leads to a genetic male developing female characteristics; it can be “complete”, “partial” or “mild” (CAIS, PAIS, MAIS); and the “complete” form is something from 1 in every 20,000 to 100,000 births.

    Even having such a condition is not a simply binary either/or; the degree of sensitivity varies; and this is a real physical issue — not some social construct.

    So this whole thing about left or right politics is flying over my head somewhat. Taking aim at nonsense about all gender differences being socially constructed would be okay; but I can’t see that in the post. The problems with gender in the Olympics have a real empirical basis — and sure, the difficulties are mainly in isolated and unusual cases. But those isolated and unusual cases exist. They are real. It’s not a left or a right thing. It’s data.

    I confess I find this whole discussion a bit puzzling. Razib even highlighted my first comment in a subsequent blog for some reason. (Razib, by the way, I was not trying to “lecture you” but to make a contribution to the conversation.)


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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