A defense of the binary in human sex

February 14, 2020 • 10:30 am

As a biologist, I get especially irked at the repeated claim that sex in humans is “a spectrum, not a binary.” In fact, as I’ve discussed several times before (e.g., here, here, here and here), sex might as well be a binary, because the overwhelming majority of people conform to the definitions of either male or female, which involve differential gamete production (sperm vs. eggs), and only slightly fewer fail to conform to a binary of other primary sexual characteristics (appearance of genitalia) or secondary sexual characteristics that appear at puberty (breasts, pubic hair, etc.).

To be a bit more precise, biological sex in humans is bimodal: if you do a frequency plot with “sex” on the X axis and “frequency of individuals conforming to that sex” on the Y axis, you get a huge peak at “male”, another huge peak at “female”, and then a few tiny blips in between that conform to hermaphrodites or intersexes.

There’s a reason why sex is a binary: evolution produces two distinct sexes who mate with each other to produce offspring. Exactly why there is sex rather than all of us budding off clones or reproducing in other asexual ways is an unsolved problem, but once there is sexual reproduction, you can construct a reasonable theory about why there should be two of them, and that they should be distinct. (A few species have “mating types” that encompass more “sexes”, but these are virtually nonexistent in vertebrates.)

Gender, on the other hand, is less bimodal, for it’s based on people’s claims of what they are, and there are lots of different socio-sexual roles that people can claim. Still, gender is also bimodal, though less binary, for the vast majority of people still claim identities of “male” and “female”. But let’s leave that aside, as today we’re dealing with biological sex.

And it’s especially galling that biologists, of all people—even evolutionary biologists, who should know better—will assert that sex is not a binary. I was appalled, for instance, when the Society for the Study of Evolution (SSE), of which I used to be President, issued a woke-ish statement that  neither sex nor gender were binary (see link below). That’s misleading for both terms, but especially for sex. Do they not know the evolutionary rationale for having distinct and separate sexes? (Answer: yes they do, but they’re trying to be woke.)

And it’s not just the SSE. As I wrote earlier:

The shameful part of all this is that the scientific journal Nature, as well as three evolutionary biology/ecology societies, who should know better, made statements or editorials that neither sex nor gender are binary. That’s a flat-out abnegation of both their responsibility and of science itself. Evolution itself produces a binary of sex! To be anthropomorphic, evolution wants a binary of sex.

A while back, biologists like me were voices crying in the wilderness, for if you say that sex is a binary, you’re liable to be labeled a transphobe. (That’s a foolish slur, for the facts about nature are independent of how we should treat transsexual or other “nonconforming” individuals.)

But now other biologists are speaking up. Two of them, Colin Wright and Emma Hilton, have a sensible column about the sex binary in yesterday’s Wall Street Journal (a conservative organ, of course: you’ll never see a claim for a sex binary in Salon or HuffPost, much less the New York Times, which ran an op-ed by Anne Fausto-Sterling denying that sex was binary).

Colin Wright  is a research fellow at Penn State, and Emma Hilton a developmental biologist and research fellow at the University of Manchester. You can see the beginning of their WSJ article by clicking on the link below, but it’s paywalled. A judicious inquiry might, however, yield you a copy:

Wright and Hilton not only give examples of the mainstream press denying that sex is a binary, but explain why that denial is wrong, and then briefly discuss the danger of this kind of misinformation. (Yes, the claim that sex in humans is not a binary is pretty much a lie, and is made on ideological rather than scientific grounds.) I’ve indented some quotes from their short but perspicacious piece:

Yet it’s one thing to claim that a man can “identify” as a woman or vice versa. Increasingly we see a dangerous and antiscientific trend toward the outright denial of biological sex.

“The idea of two sexes is simplistic,” an article in the scientific journal Nature declared in 2015. “Biologists now think there is a wider spectrum than that.” A 2018 Scientific American piece asserted that “biologists now think there is a larger spectrum than just binary female and male.” And an October 2018 New York Times headline promised to explain “Why Sex Is Not Binary.”

The argument is that because some people are intersex — they have developmental conditions resulting in ambiguous sex characteristics — the categories male and female exist on a “spectrum,” and are therefore no more than “social constructs.” If male and female are merely arbitrary groupings, it follows that everyone, regardless of genetics or anatomy should be free to choose to identify as male or female, or to reject sex entirely in favor of a new bespoke “gender identity.

To characterize this line of reasoning as having no basis in reality would be an egregious understatement. It is false at every conceivable scale of resolution.

Why sex is strongly bimodal, and for all practical purposes is a binary in humans. Here they’re talking about the rare exceptions for sex, not gender:

There is a difference, however, between the statements that there are only two sexes (true) and that everyone can be neatly categorized as either male or female (false). The existence of only two sexes does not mean sex is never ambiguous. But intersex individuals are extremely rare, and they are neither a third sex nor proof that sex is a “spectrum” or a “social construct.” Not everyone needs to be discretely assignable to one or the other sex in order for biological sex to be functionally binary. To assume otherwise — to confuse secondary sexual traits with biological sex itself — is a category error.

Finally, they argue that it’s important for society to recognize the bimodality of sex (again, we’re not talking about gender). There are a number of issues, and remember this is their list, not mine, though I’ve emphasized the effect on sports rather than the more important issues they mention here:

Denying the reality of biological sex and supplanting it with subjective “gender identity” is not merely an eccentric academic theory. It raises serious human-rights concerns for vulnerable groups including women, homosexuals and children.

Women have fought hard for sex-based legal protections. Female-only spaces are necessary due to the pervasive threat of male violence and sexual assault. Separate sporting categories are also necessary to ensure that women and girls don’t have to face competitors who have acquired the irreversible performance-enhancing effects conferred by male puberty. The different reproductive roles of males and females require laws to safeguard women from discrimination in the workplace and elsewhere. The falsehood that sex is rooted in subjective identity instead of objective biology renders all these sex-based rights impossible to enforce.

They posit an effect on children, too, and this is something I’ve thought of when I see parents hailed as heroes for immediately accepting that their children—children as young as two or three—are transgender, as they claim. Wright and Hilton posit that the blurring of sex categories in the popular literature may lead parents to contribute to confusion in their children and, on what seems to be a one-way express, ineluctably lead to their irrevocable identification as transgender kids, and then to hormone treatment and surgery. The number of these children has increased exponentially in recent years; could this be correlated with the increasing number of claims that sex is merely a social construct? Wright and Hilton think so, and their point shouldn’t be dismissed:

Those most vulnerable to sex denialism are children. When they’re taught that sex is grounded in identity instead of biology, sex categories can easily become conflated with regressive stereotypes of masculinity and femininity. Masculine girls and feminine boys may become confused about their own sex. The dramatic rise of “gender dysphoric” adolescents — especially young girls — in clinics likely reflects this new cultural confusion.

The large majority of gender-dysphoric youths eventually outgrow their feelings of dysphoria during puberty, and many end up identifying as homosexual adults. “Affirmation” therapies, which insist a child’s cross-sex identity should never be questioned, and puberty-blocking drugs, advertised as a way for children to “buy time” to sort out their identities, may only solidify feelings of dysphoria, setting them on a pathway to more invasive medical interventions and permanent infertility. This pathologizing of sex-atypical behavior is extremely worrying and regressive. It is similar to gay “conversion” therapy, except that it’s now bodies instead of minds that are being converted to bring children into “proper” alignment with themselves.

They (and I) are not of course denying that gender-dysphoric children should be treated with compassion and, if their dysphoria persists into young adulthood, begin talking about medical interventions. (I still feel this needs to wait until the mid-teen years, when children become adults and can make such decisions.) But regardless of what we do, it’s time for biologists to not only recognize the truth, but proclaim it loudly to those obfuscating scientist-ideologues who claim that sex is not a binary. And that’s the way Wright and Hilton end their piece:

The time for politeness on this issue has passed. Biologists and medical professionals need to stand up for the empirical reality of biological sex. When authoritative scientific institutions ignore or deny empirical fact in the name of social accommodation, it is an egregious betrayal to the scientific community they represent. It undermines public trust in science, and it is dangerously harmful to those most vulnerable.

Amen, brothers and sisters—and the few intermediates.

164 thoughts on “A defense of the binary in human sex

    1. Indeed. Seems everyone and their dog has a different definition of both sex and gender. No wonder that virtually everyone is riding madly off in all directions.

      But of maybe some related interest is a recent tweet by Colin Wright in which he, with some justification, takes a strip off Anne Fausto-Sterling because she is apparently saying now that her earlier “claim of there being 5 sexes was ‘tongue-in-cheek’!? …”:


    1. Indeed indeed, however in the UK, it seems that the Police are very ready to prosecute any dissenting statements that question ‘trans’ orthodoxy that they find on social media, and jail time is an actual possibility.
      UK police are famous for allowing thousands of underage young girls to packed raped repeatedly by Islamic grooming gangs.

      That is not too bad apparently but try saying you don’t think trans women are real women, and you will get a visit from the police.

      It is as absurd as that and is getting worse, let’s hope those with some standing actually can dispense with politeness without being sucked into an Orwellian dystopia or Kafkaesque absurdity.

  1. Throw in a professor of the public understanding of science from The University of Birmingham, UK who thinks Humans are Clownfish and it’s no wonder some people are confused…

    1. Ah, yes. I was puzzled too. It’s Alice Roberts, who just left Twitter because she got social-media mobbed about apparently disapproving of a gender binary. I’m not sure exactly what she said, but the story is here.

      I met Alice and quite liked her, so even if she erred scientifically, she didn’t deserve the demonization.

      1. She wasn’t really “demonised” nor was she “mobbed”. She Tweeted some woke trans ideology. People replied, disagreeing with her. She labelled that disagreement “hate” and refused to engage. She then left Twitter saying how “hateful” people on Twitter are.

          1. I think biological essentialism is the opposite of evolution organisms contain all that is required to serve a purpose and do not change because they are all put together and ready to do whatever it is they do, instead of changing through time as they adapt.

        1. Biological essentialism is the view that your biology determines who you are – if you’re female, you should behave in certain ways, if you’re male you should behave in other ways.

          Her statement seems odd to me, though, because transgenderism uses that argument in reverse – if you like stereotypically feminine things, you must be a woman, if you like stereotypically masculine things, you must be a man.

        2. I found the following helpful explanation somewhere on the Internet:

          Not biological essentialism: a Chinese person is a person from China.

          Biological essentialism: Chinese people are inherently good at math.

          Uber biological essentialism: People who are good at math are Chinese.


          Not biological essentialism: A woman is an adult human female.

          Biological essentialism: A woman is an inherently feminine minded person.

          Uber biological essentialism: A feminine minded person is a woman.

        3. “Essentialism” sure is a murky topic. Though maybe some justification there for Nietzsche’s quip that too many “philosophers” have “muddied the waters to make them seem deep”: job security writ large.

          But something of interest and relevance from Wikipedia – “The People’s Encyclopaedia”, to coin a phrase:

          Essentialism is the view that every entity has a set of attributes that are necessary to its identity and function. …. Essentialism has been controversial from its beginning.

          See: https://en.wikipedia.org/wiki/Essentialism

          Bit of a puzzle as to the reason for that “controversy”, although I think it’s partly because so many of us don’t realize that categories are just abstractions, and therefore insist on turning them into real things – the “sin”, the logical fallacy of reification.

          And that reification is no more evident than in the too common insistence, most notably by gender-critical feminists, that “sex is immutable”, that there’s some ethereal essence in the categories “female” and “male” that is infused into our bodies if not souls at conception, and remains with us at least until we shuffle off this mortal coil.

          To insist any categories are “immutable” seems as untenable as insisting that the musical note C-sharp weighs 10 pounds: the adjective is simply inapplicable to the noun. We either possess the trait that confers category membership or we don’t; we get a membership card when we have or acquire the trait, and then get the card revoked when we lose it.

          Seems the “essence” is in the category definition, not in the individual – a conflation that causes no end of quite unnecessary grief.

          1. There is no reification going on among GC feminists around sex. We *observe* that there are two sexes as an empirical fact. We *observe* that in most species (like humans) that it is immutable.

            Where reification is going on is the abstract notion of gender (as a set of socially constructed relations between stereotypical roles, appearances etc as mapped to the sexes) is turned into the intrinsic concept of gender identity.

            Sex is a material reality. Gender identity is an ideological construct foisted on people.

            1. That assertion of “no reification” seems entirely contingent on what we decide “sex”, “male”, and “female” mean in the first place. And it probably qualifies as “begging the question” as those definitions are very much a “bone of contention”, so to speak. Particularly as more than a few transwomen are claiming to be “female”, are claiming many of the rights and much of the cachet that normally attends that “exalted” state.

              But more particularly, IF one accepts the standard definitions that say “male” and “female” are categories – i.e., abstractions, mere perceptions of shared traits – based on the actual ability to produce sperm and ova THEN insisting sex is immutable is clearly a case of turning that abstraction into a real thing – reification writ large. Particularly as it is quite obvious that those abilities, particularly in humans, are not anything that any of us possess from conception to death.

              See: https://www.lexico.com/en/definition/sex

              And it’s been rather amusing, if somewhat depressing, to see so many GC feminists, particularly on Twitter, insist that sex is immutable when they are clearly unable to say precisely what it is that is, in fact, “immutable”, that actually qualifies as our “males” and “females”. Doubt any of us could weigh those, measure their volumes, calculate their densities, locate them 3 cm to the right of our spleens.

              Karyotype might reasonably qualify as “immutable”, and genitalia somewhat less so. But neither of those traits are any part of the stated definitions – something underlined by the previously mentioned tweets of Dr. Hilton. As she rather brilliantly asked, “How can we track SEX CHANGE [my emphasis] in sequential hermaphrodites if we don’t know what sex is?”

              While our sexes seem to be common euphemisms for our genitalia – see the above definition, our genitalia are, in themselves, most certainly NOT our sexes. About the most that could be said for our genitalia, and for our karyotypes, is that they are mere proxies – “a measured variable used to infer the value of a variable of interest” as Wikipedia puts it.

              And in that case, it seems a serious misapprehension to say that “sex is assigned at birth” when it is more scientifically accurate to say that, based on the observed proxy of genitalia, the child is likely to acquire a particular sex at puberty, a sex that strongly correlates with particular genitalia but is hardly proven by it. Hardly consistent with any claim of “immutable”.

      1. Prof’ Roberts, and others like her, make a simple error in logic. Sex as a binary does NOT entail biological essentialism. Biological essentialism says that your sex determines EVERYTHING that you are, which is basically chauvinism. Typical throwing-out-the-baby-with-the-bathwater nonsense due to illogical thinking. They don’t recognize that a (questionable) inference has been made in the argument, they go straight to denying clear and obvious facts.

        Since it’s biological essentialism and its attendant chauvinism they’re afraid of, the battle needs to be joined at the issue of whether the biological fact of binary sex entails chauvinism. The two are consistent with each other, but it’s equally consistent to recognize binary sex and deny biologial essentialism.

    2. Can you please give a link to what exactly she said?
      I’m aware of why you mentioned Clownfish, but does she really believe that people are capable of sequential hermaphroditism? Ancient Greek folklore has numerous examples of such, but that’s folklore.

      As for transsexual fish, I’m kinda partial to the black sea bass, which are protogynous hermaphrodites.

      1. She kept it vague but attempted to muddy the water by bringing up clownfish as an example (clownfish can change sex)

        “I’ll bet your school biology told you species couldn’t interbreed and have fertile offspring either… biology is, quite simply, messier and more wonderful than some people would like it to be. Ask a clown fish! ”

        She didn’t mention that the human lineage and clown fish lineage parted company 435 million years ago.
        Also, clown fish change sex without the aid of a team of surgeons and a lifetime of artificial hormone consumption.

        1. Even “a team of surgeons and a lifetime of artificial hormone consumption” does not change a human’s sex.
          Nothing changes a human’s sex. 😉

      2. Couple of tweets by Roberts that may shed some light on her PoV:



        The second is of maybe particular interest because the thread features some quite cogent comments by Dr. Emma Hilton, one of the more sensible, though not perfect, commentators on the whole issue:

        What biological feature unifies ‘male’ and/or ‘female’ across all anisogametic sexually-reproducing species? 1/

        How can we track SEX CHANGE [my emphasis] in sequential hermaphrodites if we don’t know what sex is End/

        However, it also seems that Roberts is changing horses in midstream – always a recipe for disaster – by switching from talk of sex to talk of gender. An all-too-common though quite problematic conflation.

  2. I’m convinced that a significant part of Trump getting elected was blowback, because of this type of stuff. Throw in people like AOC clamoring for open borders, and I’m more surprised I didn’t see him beating Hilary.

    1. Yes, I agree. The PC thought-police have become so Maoistically intolerant, AND untethered from reality, that anyone who stands opposed to them must ipso facto hold an attraction to a lot of people.

    2. Quite a bit of justification for that argument.

      Democrats seem only stop shooting themselves in the feet to reload before repeating that.

      1. I am glad you used “feet” because “foot” is not adequate. The Dems have lost focus on the Orange Felon and keep beating up on each other which is an advantage only to Trump. If they cannot come to some sort of unified message, count on four more years of a rogue POSPOTUS

        1. 🙂 Certainly a lot of that goin’ round these days. And Britain is certainly not immune to that particular “disease” either. Consider:


          Sad and unfortunate in both cases. Some credible positions on the leftish side of the political spectrum. But as long as so many of them insist on throwing their lot in with the “Wokeus Dei”, so long will they be obliged to wander in the political wilderness.

  3. Sadly, this information would have been useful for me growing up. Unfortunately, I did not receive any formal training in evolutionary biology. Not in high school and not at university. And now it is not much better. In Ontario, Canada, there is no mention of evolution until Grade 11. NONE in the grade 12 bio. And NO human evolution whatsoever. COWARDS!!

    1. We didn’t need evolutionary biology classes in high school, ANY biology class teaches the sexes, reproduction, gametes, etc. You KNEW that humans were two sexes. Everyone knows this, it was just easier to tow the pop culture line.

  4. The authors write: “Women have fought hard for sex-based legal protections. Female-only spaces are necessary due to the pervasive threat of male violence and sexual assault.”

    The authors seems to be saying that a practical reason for recognizing the bimodality of sex and the creation of female-only spaces is that males (or at least most of them) are always on the hunt to physically hurt women and commit rapine. Is this really true biologically or is it a way for the authors to claim they are as radical feminists as anyone while still denying that sex is on a spectrum?

      1. Plus there’s also the advantage of keeping ‘your’ man away from temptation to stray because of other women competing with you for a better mate.

    1. Your question sounds suspiciously akin to the “have you stopped beating your wife” form of query.

      I do believe I don’t understand what you’re getting at.

      1. What I am getting at is that the rationale the authors give for the necessity of female only spaces is to protect women from men on the hunt to physically hurt or rape them. I am asking if men by their biological nature are natural predators against women. Even if they are wrong, this assertion would find favor with a certain group of feminists that have no use for men.

        I would also point out that if the assertion is true and women cloister themselves in female only spaces for protection against men, they would still be in danger when they emerge from these spaces.

        My conclusion is that unless, in fact, men are natural predators against women this assertion is a very poor argument for the bimodality of the sexes.

        1. I suspect you may be getting twisted around the wrong pole here. The need for separate areas for women are many, and not having anything to do with protection from the male. Co-ed bathrooms or dressing rooms do not seem appropriate to me. Do we have women’s colleges to protect them from males. Men’s colleges to protect them from women?

          This new think culture seems to be confusing both extremes.

          1. I am not denying that there are good reasons for female only spaces. But, again, unless there is a scientific basis that men are natural predators against women then this reason cited by the authors is not a good argument for the bimodality of the sexes, which, by the way, I have not denied in any of my comments.

            1. Good grief H:

              Not all biological males are predators, but most predators are biological males: 1) most violent crime in general, sexual assault in particular is perpetrated by biological males. Most partner assault and homicide — biological males. Most stranger assault — males.. That’s true in western societies, and apparently in most human societies. My bet is that Pinkerization is taking place — that over time and over socio-economic progress, things are getting better.

              2) Unspoken premise [I assume, I haven’t vaulted the paywall] is that male predators [and non-violent male perverts] are attracted to ‘women-only spaces’. I’d trust women’s rape-dar here.

            2. The author is not using the supppsed need for female only spaces as an argument for the bimodality of the sexes, but is pointing out that rejection of bimodality leads to the elimination of female only spaces.

        2. Hmmm. I do not think they used this as an argument for the bimodality of the biological sex. In fact, they don’t make any kind of circumstantial argument. They state that the bimodality of biological sex is a scientific fact. Because it is. There simply can be no denying this; the outlier intersex and other variations are themselves proof. I am continually flabbergasted that so many have difficulty with this (not saying you don’t, Historian).

          Anyway, they use that argument as an example of why denying this scientific fact can have real world repercussions.

          That’s how I read it.

    2. “… is that males (or at least most of them) are always on the hunt to physically hurt women and commit rapine.”

      Or rather, some *minority* of them (with members of that minority not necessarily being easy to discern).

      1. Maybe they did mean a minority of men, although the word “pervasive” suggests otherwise. At best, this sentence is poorly written because it lends itself to varying interpretations of its meaning.

          1. They could mean it in the sense of Historiqn’s point (about the link between biological male sex and a propensity to violence towards women); that it is pervasive throughout human cultures and over time.

            It kinda is, which does suggest a male sex-linked component to the behavior. Still, I do not believe this is particularly strong case for the consequences of not accepting that biological sex is biomadal

    3. The authors seems to be saying that a practical reason for recognizing the bimodality of sex and the creation of female-only spaces is that males (or at least most of them) are always on the hunt to physically hurt women and commit rapine.

      I don’t think they are saying that. I think they are saying that a consequence of not recognising the bimodality of the sexes might be the erosion of women only spaces and this is bad.

      Oh and the provision of women only (and men only) spaces is not predicated on the actual danger women are in from men, but on the perceived danger or even perceived discomfort. If you are a woman who has just been raped or otherwise abused, you probably have an issue with trusting men. You might find it difficult to deal with your assault when there are men in the room even if intellectually you know you are in no danger from them.

    4. I seem to recall that in India or Pakistan female only train cars have been set up. This would not be as appropriate in the West, but maybe the local culture makes it reasonable.

    5. I disagree. I didn’t read those paragraphs as claiming men are “always on the hunt to physically hurt women and commit rapine.” I read them as acknowledging that men are much more likely to commit violence. Which, statistically, is true. But it doesn’t imply anything about all men or even your ‘average’ man.

      Here’s an analogy: I say you are much more likely to get an STD if you have sex without protection. Have I implied that 100% of people having sex without protection will get an STD? Of course not. Have I implied that everyone having sex without protection is equally likely of getting or passing on an STD? Of course not.

  5. Typo maybe?

    “…if you say that sex isn’t a binary, you’re liable to be labeled a transphobe..”

    ‘is’ for “isn’t” ?

  6. The way I see it, claiming that sex in humans isn’t binary because of outliers like intersex people is the same as saying humans aren’t a bipedal species because some people are born without fully developed legs.

      1. Slightly fewer…

        Sorry. It’s a sickness. I have a very difficult time resisting. I’m honestly embarrassed, but I’m also all but compelled. Ask my family…or at least, ask the few members of it who still speak with me.

        As a matter of substance, of course, you’re absolutely right.

        1. I just noticed a colleague wrote “lead” when he meant “led” on a wiki and I had to resist fixing it/commenting on it because it looked weird that I even read the wiki entry to begin with and I didn’t want him to think I was judging everything he wrote.

        2. I’m usually happy if I can get my point across even if it isn’t written perfectly. I identify as a non-grammarian, my brain don’t work too good sometimes.

          1. That’s what I really like about this site. You’ll find a sense of camaraderie that’s easily inclusive of all grammatical comfort levels. I’m chuffed. 😉

        3. Well, if we are going to be precise, the AVERAGE numbers of legs, etc. are real (floating point) numbers even though the data items are integers, so maybe saying “less” rather than “fewer” is defensible in this case. Or at least, it’s, ahem, less of an error than it first seems.

    1. Exactly. Furthermore, almost all intersex people can be easily classified as “male with ABC syndrome” or “female with DEF syndrome”. E.g. you don’t stop being male or female just because your body has reduced hormone sensitivity, or because you have an extra copy of a sex chromosome, or because your genitalia are deformed. To the extent that they can participate in sexual reproduction, they do it with sperm and eggs like other males and females, even if they need assistance with the delivery. None of them constitute a “third sex” in the sense of being able to reproduce with anything other than sperm or eggs.

      In fact, the only people that I think can’t be easily classified are true hermaphrodites, and as far as I know those are (almost?) always chimeras – a kind of extreme case of conjoined twins where two or more embryos fused together into a single person. But they still aren’t a third sex.

      1. Yes. The trans activist co-option of the phrase/concept “assigned (male)(female) at birth” from intersex gets its traction from the antique image of a doctor faced with ambiguous genitalia who quickly guesses whether the newborn is probably a boy, or probably a girl, snipping here or there accordingly.

        In fact, the same situation today is immediately met with a great deal of sophisticated technology in trying to determine what, exactly, the developmental issue may be, since some conditions require immediate medical treatment.

      2. Conceptually only, there is another conceivable category: someone who has no sex cells at all and never did. “Neither” would seem to apply – the exact opposite of the “both” of the true hermaphrodite. Does this occur in humans ever? I imagine they’d have trouble growing, what with less to no “sex hormones”, etc.

  7. A similar issue, if I may, is the claim now often made, e.g. this from Adam Rutherford:

    “There is now a vanishingly small number of geneticists and evolutionary biologists who [dispute] that genetics has clearly demonstrated that race is not a biologically meaningful categorisation”.

    One could interpret this as saying that everyone now rejects the idea that there are “races” that are clearly-defined, discrete and countable.

    But, humanity does show shared-ancestry clusterings in a fuzzy-edged branching structure (though this structure is now being blurred by relatively easy mass migration).

    And fuzzy-edged branching structures are real and “meaningful”. And that shared-ancestry clustering is the basis behind the notion of “race”. And that fuzzy-edged branching structure can indeed be seen in our genes (as companies such as 23andme demonstrate).

    So do statements such as Rutherford’s amount to virtue signalling (“I’m so anti-racist that I’ll deny that races even exist”)? Denying that there is a “biologically meaningful” concept underpinning notions of “race” seems to me to be going too far.

    1. I’m predisposed towards Rutherford, liking his books, and myself not very knowledgeable, so maybe need teaching, but nothing like his phrase “..biologically meaningful categorisation..” appears below in your analysis, nor anything else really biological, I think.

      The gradual spectrum of easily detected, but often very superficial, differences, as one travels all around the world, is of course obvious. No question it’s very much more continuous than discrete. And there are coming to be understood some DNA connections as well, as the struggle with the very difficult macro versus micro is slowly being partially understood. Or so I understand.

      Of course, IQ is a big one, but I doubt any claims to isolate results here from the environment have ever been convincing, at least as far as claiming IQ to be a good measure of general brain competence. The word ‘intelligence’, for us all, is almost as bad as ‘exists’ is for philosophers.

    2. I think Rutherford is right. Look at Barack Obama, the first black president.

      Except his mother was white and she was the one that raised him. The only thing that makes Obama black is certain superficial characteristics.

      Then again, what is “black”? Is it a race? Is a Nigerian born and bred the same race as a black person from Detroit?

      1. Certainly “black” is not a race (in the sense that it’s not a “clade”). But it would be wrong to identify the entire concept of “race” with the particular usage of terms in one place (the US) at one time (now).

        Yes, the “one drop” idea is a social construct, but the underling concept about race, namely that humans show shared-ancestry clustering (with fuzzy edges) is valid and real.

      2. I recall that during Obama’s first inauguration some contemplated (questioned?) whether Obama was “black enough.” It was not people of non-color who were so contemplating.

    3. I want to read Rutherford’s new book, How to Argue with a Racist. According to the review I saw, it’s largely based on the fact that an average person has a high chance of becoming an ancestor to the entire local population within surprisingly few generations, and gene exchange between populations will soon make them an ancestor to the entire global population. (I first encountered this astonishing claim in a footnote to The Selfish Gene, and it seems to be true.) Thus, every Nazi has a Jewish ancestor, and every white person has an Australian aboriginal ancestor, etc. And the most recent common ancestor of all humanity might have lived as recently as 3600 years ago, so racism makes no sense because we’re all mixed, with no separate lineage. Maybe he makes other points, but that’s what the review focused on.

      But I find this to be rather disingenuous. Using Rutherford’s estimate for generation time (25 years), 3600 years is 144 generations. Assuming 50,000 genes in the human genome, beyond 16 generations there’s less than a 50% chance of directly inheriting even a single gene from an ancestor, and at 144 generations the chance is nil, about 2.2 x 10-39. Now that doesn’t necessarily mean they left no trace at all, but these global common ancestors don’t do anything to prevent the evolution of distinct subpopulations of humanity as long as those populations remain mostly isolated from gene flow, which they did until the revolution in transportation which took place in an evolutionary blink of an eye, and which still remain sufficiently isolated due to mating preferences.

      Perhaps the book makes some other arguments which are better, but I wasn’t hopeful after reading the review.

      1. “…an average person has a high chance of becoming an ancestor to the entire local population…”

        And 4,000 years ago, a high chance of becoming an ancestor of today’s entire human population!! Much before that, and the ‘only’ obstruction to someone being ancestral, to every one of us now, was being the ancestor of absolutely nobody today, that likely happening very soon, like if you died at 10 years or minutes old. We all have lots of common Neanderthal ancestors I bet, that including those now in the middle of Africa, despite them having no DNA traces. Think of 2 to the power 100, roughly 100 generations of possible ancestors then, generously taking 37 year average generation. That number is easily seen larger than 1 followed by 33 digits. We got lots of base pairs, but laughably less than that.

        This is also Rutherford, in “A Short History of Everyone who Ever Lived”.

        But do many racists have any ability to change their tune based on scientific fact?

        It’s easy to find this hard to swallow, with these formerly very isolated populations, Amazon, Greenland, mid-Africa, esp. Australia/New Guinea and the Americas-Eurasia separation. But he starts with a chapter including the word “horny”. And isolation is never complete– Aussie aboriginal isolation meant ‘from Europeans completely’ maybe, but that’s the jargon then.

        This is due to Chang, a Yale mathematical statistician, in around 1990. He revised 3400 up to 3700 years by adopting a much more stringently conservative set of assumptions, such as only one person (accidentally presumably) ending up across the Bering Strait, from northwest Siberia to Alaska, every few decades, IIRC. This was thousands of years after the land bridge during the ice ages.

        There are ancestors of the entire present human population who lived 3700 years ago, about 1700 BCE–(e.g. from Vietnam maybe?).

        So much for the Nazi religion.

      2. To add, after reading yours properly:

        So you, and me, plus all of us from New Guinea, are descended from almost every human who lived 5000 years ago who happened to have descendants still surviving after 10 generations maybe. But each of us has no genes at all from almost all of them (but all our genes do come from some of them of course). It seems clear to me that the actual genes any one of us have must come from a completely random collection of places around the world. How could it be otherwise?

        If so, is that not a strong enough thorough rebuttal of racists, if DNA, not simple ancestry is their supposed bullshit basis?

        I must admit I do not understand how someone could explain how a certain gene of mine came from my mother, not my father, in the case of genes they happen to have in common. That requires actual expertise in microbiology I think, if it’s even the case. But the argument above surely doesn’t depend on that.

  8. “Not everyone needs to be discretely assignable to one or the other sex in order for biological sex to be functionally binary.” Sorry, not seeing it. If you don’t fit either binary, do you then have no sex? (And even then, why does “asexual” not count as a third category?)

    The authors seem to want to go beyond just pointing out that MOST people fit under male or female biological sex. But … why?

    1. If there were no genetic or developmental disorders, all humans would be male or female. In that sense, humans are a species with exactly two sexes.

      Do any disorders produce a “third sex”? In the biological definition of sex, it seems it would not. If they can participate in reproduction, they do so in the usual way: with sperm or eggs. (Biological sex is defined more by gametes than genitalia; there’s a huge variety in delivery mechanisms, but eggs and sperm are virtually ubiquitous. Even plants produce them.)

      If they can’t participate in reproduction, then you have to start splitting hairs, I suppose. If a person lacks gamete-producing organs because of a mutation to the genes that would have produced testes if they hadn’t been mutated, then I’d call that person a male, albeit a defective one. You could also legitimately say that person is asexual. They don’t reproduce asexually; they’re completely out of the reproduction game. You could call it a “third category”, but I don’t think you can call it a “third sex”.

      To some extent there is a conflict between the modern biological definitions on the one hand and colloquial and historical definitions which define males and females by externally observable features on the other. Perhaps the biological definition is not always appropriate when deciding social policies, but saying we have a spectrum of biological sexes doesn’t seem accurate.

      1. I was always under the impression that “asexual” meant that a person felt no sexual urges and wasn’t interested in having sex, and I do think that’s the way it’s interpreted these days. Please correct me if I’m mistaken.

        1. Asexual in the paultorek’s comment should be “intersex” and asexual in Adam M’s and Jenny’s comments should be “non-reproductive” or “non-sexual”. Otherwise, the discussion gets rather confusing, since these are rather non-standard usages.

          In biology, as I once heard Robert Trivers point out in a talk on youtube, asexual refers to females that don’t need any stinkin’ males to reproduce. Granted, that doesn’t seem like a standard usage either, since the implication is that bacteria are female. But it actually hits the nail on the head. Bacteria ARE female. It’s a female planet. Too bad many biologists don’t embrace this aspect of the terminology. It’s strikes me as most insightful.

        1. “Third category”, indeed. And “sexless” seems an inescapable conclusion.

          And a conclusion that, as you said, Wright and Hilton “seem bizarrely reluctant to acknowledge”.

          A real puzzle as to why that is the case. Although it is certainly quite common that so many people insist that we all have to have a sex, as if we’re non-existent if we’re sexless; as if “male” and “female” are essential elements of our psyches, of our identities; as if we’re destined to wander forever like disembodied wraiths without one or the other of them.

          And a real puzzle as to why so few are willing to accept what seems quite obvious that the words are just labels for quite transitory and circumscribed biological capabilities, i.e., the ability to produce sperm or ova as part of the process of reproduction.

          Although of maybe some related interest is a tweet by, apparently, one of the more sensible transactivists around – and there is, fortunately, more than a few of them – with something of a credible point:


          Seems reasonable to argue that the conventional definitions for “male” and “female” are in fact “gamete-centric”. However, that seems far more consistent with the definition of sex which seems to make the ability to reproduce as the “necessary and sufficient condition” to have one.

          1. “And a conclusion that, as you said, Wright and Hilton “seem bizarrely reluctant to acknowledge”.”

            We absolutely acknowledge the fact that not everybody may be *neatly* assignable to either male or female, even though the vast majority can. See the 7th paragraph of the essay.

            This is what “intersex” means. We are reluctant to refer to intersex people as simply one thing however, because there are a wide variety of intersex conditions with a variety of etiologies. Intersex is just a catch-all umbrella term for sex ambiguity and/or a mismatch between internal primary sexual anatomy and external phenotype.

            We don’t insist every living human must be assigned a male or female sex. I can’t speak for Dr. Hilton, but I think intersex people should be largely allowed to indicate they’re a 3rd category, or choose if they wish to be legally male or female, depending on their condition. I also think that sporting leagues, for instance, should be able to define male and female differently based on their own criteria to ensure their leagues and events remain a protected category.

            I hope that helps clear some things up. Thanks for the discussion!

            1. Thanks for your response. And thanks for the WSJ article, though I hope you’ll publish it for a wider audience as soon as possible. 🙂

              However, I’m not sure that you’ve really addressed my or Paul’s point as to how you would characterize that “third category”. You say, in that same paragraph:

              There is a difference, however, between the statements that there are only two sexes (true) and that everyone can be neatly categorized as either male or female (false). The existence of only two sexes does not mean sex is never ambiguous. But intersex individuals are extremely rare, and they are neither a third sex nor proof that sex is a “spectrum” or a “social construct.” Not everyone needs to be discretely assignable to one or the other sex in order for biological sex to be functionally binary.

              It’s nice that you argue that the intersex are not a third sex, and I agree entirely. However, the question that you and too many others are apparently evading, even if for maybe commendable reasons, is whether the intersex are either male or female – or whether they’re of neither sex. I appreciate that not “everyone can be neatly categorized”. But that something isn’t easily categorized shouldn’t preclude stipulating precisely what the membership criteria are: it may well be difficult to determine whether any large odd number is a prime or not, but the criterion – divisible only by “1” and itself – is easily stated and grasped.

              And it seems that the criteria you’ve advanced in the WSJ article – “reproductive anatomy” – and in your Times letter – “past, present, or future functionality” – are simply too vague and incoherent to be of much use. If you can’t state clearly which criterion is the “necessary and sufficient condition” for sex category membership then how can you possibly decide in any particular case, much less ambiguous ones? As Dr. Hilton herself put it:

              How can we track SEX CHANGE [my emphasis] in sequential hermaphrodites if we don’t know what sex is?

              And her tweet (above) – and many others besides – seems rather clear in stipulating that it’s the actual ability to produce sperm and ova for reproduction – not past or future abilities – that is that criterion for membership.

              Seems that too many of us don’t realize how the definitions for categories work or where they often come from. We can’t prove that the words “prime number” denote a number divisible only by “1” and itself – we say that’s what the word means. Likewise with the words “male” and “female”: we say they mean “produces sperm” and “produces ova” – they’re “true” as such, by definition:


              1. Thanks for the comment. We will definitely publish it elsewhere once we retain the rights to it in a few weeks! So glad you enjoyed the essay. And just to be clear, we are not trying to “evade” anything. Perhaps we were not as clear as we could have been in some parts, but it that’s the case it certainly wasn’t intentional as “evade” suggests!

                We would label most intersex conditions to be sex-specific,though there may be extremely rare instances where sex is not objectively determinable. “Neither” seems appropriate in these cases.

                We use the reproductive anatomy definition because this is how *individuals* are actually sexed. Adolescents do not produce gametes, and neither do post menopausal women or individuals who for whatever reason have non-functioning gonads but otherwise normal sex development. Individuals with dysfunctional reproductive anatomy who still have otherwise normal genitalia still are either male or female. Likewise, individuals who have had their gonads removed surgically or by accident don’t cease to have a sex. We don’t think that the actual ability to produce certain gametes is a good way to assign sexes to individuals.

                Gamete type is a good, zoomed-out definition for males and females when describing the role of sex type in the process of reproduction generally, but the actual ability to produce gametes is not how we tend to assign sexes to individual organisms.

                I hope this makes sense!

              2. Colin Wright,

                I’ll look forward to seeing your and Dr. Hilton’s article. 🙂

                But sorry to see that you’re catching grief for your “social contagion” comment – somewhat amusing and ironic that the far too common phenomenon of “mass denunciations and character assassinations” qualifies as exactly that.

                However, I’m curious as to how you can justify your rather idiosyncratic and “most illogical” re-definition of “sex”, “male”, and “female”. Particularly in the face of the standard ones in which functional gonads are essential elements, and which have apparently been around for the last 140 years – basically since the discovery of gametes in the late 1800s.

                While I appreciate that you’ve conceded, apparently, that some intersex people might reasonably be described as not having a sex, I think one might then reasonably ask you where, in a progression of chopping off various bits, one crosses a threshold from having a sex to not having one – which you’ve conceded is an actual state. Seems rather wooish at best.

                As I mentioned in an earlier comment, you and Dr. Hilton – and far too many others – seem rather desperate to decouple “male” and “female” from “sex”, and apparently think that one can engage in sexual reproduction – the essential element, the sine qua non, of the “sex” category – while not actually possessing the gonads on which that entire process crucially depends.

                And as I mentioned & linked, you might consider that the “male” and “female” subcategories are essentially the differentia within the genus or parent category of “sex”. And one simply cannot be a member of a subcategory if one does not meet the membership criteria for the parent category, i.e., in the case of “sex”, “reproductive function”:

                See: https://www.lexico.com/en/definition/sex

                Defining words and categories is not a free-for-all: there IS some rhyme and reason to that entire process – generally the science of taxonomy. It is simply not a case that anyone can create any definitions they want simply to comport with their political or philosophical dogma; with their vanity, or their envy. Rather profoundly depressing and disconcerting to see otherwise credible scientists engaging in what seems little more than Lysenkoism.

              3. What on Earth are you on about Tom? Lysenkoism? Are you serious?

                It has now been explained to you. We can sex an organism by which development path it has undergone.

                I do hope yo accept that organisms like us have two distinct and evolved development paths with respect to gamete type. That is how an organism acquires a sex. Disorders can occur upon each pathway of course, like any developmental pathway. And there is no requirement in this view for an organism to successfully reproduce or even produce gametes in order to have a sex.

              4. LeCanardNoir (LCN):

                LCN: Lysenkoism? Are you serious?

                Quite serious, though I DID say “borders on Lysenkoism”, and “seems little more than Lysenkoism”. Certainly not in the sense of “rejecting natural selection”, but in the sense, as I said explicitly, of redefining “sex”, “male”, and “female” in a logically incoherent way to “comport with political or philosophical dogma”.

                And that dogma is the entirely untenable, if not frankly risible, idea that “sex is immutable” – based, apparently, on some ethereal essence that humans in particular, and apparently by special dispensation, possess from birth to death. And an essence that miraculously grants category membership even despite the removal of the gonads which are, so I’ve been told, more or less essential to the process of reproduction which is, in turn and by definition, part and parcel of the category called “sex”.

                Dogma that’s as risible as the Trinity; as Thomas Jefferson put it:

                Ideas must be distinct before reason can act upon them; and no man ever had a distinct idea of the trinity.

                And Hilton’s and Wright’s brand-new, freshly-minted, re-definitions sure can’t be said to be “distinct”.

                LCN: It has now been explained to you.

                You mean the way that Ken Ham might “explain” to Jerry that the Earth is 6000 years old? Just saying something is true hardly qualifies as proof that it is. Particularly in the face of the evidence I’ve given that Wright’s & Hilton’s re-definitions are logically incoherent at best.

                LCN: And there is no requirement in this view for an organism to successfully reproduce or even produce gametes in order to have a sex.

                Don’t think you quite get that your “view” is logically incoherent, and that just asserting it as if it was gospel truth is little more than begging the question at best. In addition, it is totally inconsistent with the dictionary definitions I’ve quoted that stipulate that functional gonads are, in fact and in effect, the sine qua non for membership in the sex categories, “male” and “female”:

                See: https://www.lexico.com/en/definition/male

          2. Tom,

            As a transgender female, I have reflected somewhat on Professors Wright and Hilton’s letter to the Journal, and I think that they are embracing some sort of biological determinism, or, at the very least, others will draw that conclusion from their article.

            In short, they are denying the existence of human free will. Even if consciousness is the sole result of brain activity (which seems likely), hard determinism can never be proven, or, even known. Like the famous halting problem of Turing, how could we, as human beings, ever conclude that human free will does *not* exist??

            The same is true of gender. Even assuming that all human beings can be classified as being biological male or female, the human brain is, arguably, much more complex than sperm, eggs or gametes. I, for one, do not know why, or, even care much, over my presentation to myself and the World as being female. All that I do know is that if I was forced to live the rest of my life alone (say, being abducted by aliens only to be dropped off on some very distant, yet habitable World), that I would live the rest of my life as I am living it now. And, while I would so very, very much miss my wife, children, family and friends, I would be at peace with myself and with my identity.


            1. Dawn,

              Thanks for your response; a complex and thorny issue.

              But to digress for a moment, I agree somewhat with your comments about determinism. I expect that the concept of “free will” is rather like the concept of “God” – rather difficult to prove that He/She/It actually exist – or not – if we can’t even define precisely what we mean by those terms. I think it’s reasonable to argue that we have at least some degree of free will – analogous to the term “degrees of freedom” that is used extensively in statistics, engineering, and physics.

              However, while I certainly agree that the brain is incredibly complex – “the final frontier” in many ways, I think you and too many others are conflating “sex” – as a description of reproductive capability – with “gender” – typically or commonly seen as a rough analogue to personality, of which there are billions and billions. And while I can sympathize with your desire for “presentation as being female”, I think “we” – society in general – simply have to accept that there’s a profound difference between “presenting as X”, and “being X”. If I dress up as a surgeon then that does not mean I AM an actual surgeon, and should be entitled to wander around hospitals as such and get called in to remove Mrs. Jones’ gallbladder.

              Which is sort of my objection to the efforts by Drs Wright and Hilton to redefine “sex”, “male”, and “female” in their own rather idiosyncratic and logically incoherent way – which I think borders on Lysenkoism and biological essentialism. They seem rather desperate themselves to decouple “male” and “female” from “sex”, apparently thinking that one can engage in sexual reproduction – the essential element, the sine qua non, of that last category – while not actually possessing the gonads on which that entire process crucially depends.

              They seem not to realize that the current definitions for “male” and “female” – with their reliance on functional gonads – have apparently been around for some 140 years, ever since the discovery of gametes in the late 1800s. In addition, there’s an equally long-standing justification to see those categories as essentially the differentia within the genus of “sex”. One simply cannot be a member of a subcategory if one does not meet the membership criteria for the parent category, i.e., “reproductive function”.

              See: https://en.wikipedia.org/wiki/Genus%E2%80%93differentia_definition

              Many seem not to realize that defining words and categories is not a free-for-all: there IS some rhyme and reason to that process – generally the science of taxonomy. It is simply not a case of anyone can create any definitions they want simply to comport with their political dogma. There was an interesting essay at Quillette (“Words Lose Their Meaning at Wilfrid Laurier University”) that underlines that point:

              Though different literary forms, the key message of both works [1984, & Politics and the English Language] was the same: beware any person or group that redefines words so that they no longer align with facts, common sense, and common usage.

              Rather profoundly depressing and disconcerting to see the same disreputable shenanigans being perpetrated by otherwise credible scientists.

      2. The definition of biological sex is for convenience in designation, but it should not be taken to be isolating the true facts of the world in toto. The real world phenomenon that the definition seeks to distill is that males and females each tightly cluster in the many-dimensional space of phenotypes; this clustering is very highly, but not perfectly, correlated with gametic phenotype (with gametes forming an actual binary). The existence of rare overlap along some of these dimensions is real. It’s not obvious why the definition should take precedence over the facts, which do not point to a binary categorization, but rather an extreme bimodality. The recognition of the exemptions matters in biology and in social life.

  9. Since the occasional production of ligers and tigons demonstrates that the concept of “species” is a mere social construct—as woke academics and the NYT will soon instruct us—I trust nobody will deny my right to choose my own species. I like to think of myself as Ailurus fulgens, the irresistibly attractive Red Panda, although on weekends I prefer the identity of Nycticebus, the Slow Loris.

    1. Never assume someone’s species orientation. To quote my niece when she was a 3-yr old and was crawling around on the floor like what I assumed was a d*g, she replied quite simply : “I is a turtle.”

  10. I understand that the ‘bimodal’ pattern of sex is very close to a binary in terms of numbers of persons along this distribution. But in the interest of acknowledging that there is still real people at all points in this distribution, I prefer the term ‘bimodal’ and don’t wish to use the term binary.

  11. Forms in doctor’s offices and emergency rooms ask you to check sex male or female. A transgender checking female would surprise the doctor by asking if it was time for a prostate exam. There blood tests snd other tests done for each sex. Forms should ask for both sex and gender.

      1. You’re missing the entire point of the genderist crowd was exactly to erase sex for the feelings of gender. They will not accept two boxes. Radical feminism has been proposing the two box alternative for decades, but genderist want gender to erase sex.
        People are being naïve about this.

          1. I think that this whole conversation is one of pounding on open doors. As a transgender female, I am a biological male and I have always accepted that as such. As others have pointed out, absolutely nothing can be done to change this immutable, biological fact of life and reality.

            As a transgender female, all that I (and, others like me) desire is full equality under the Law, nothing more. Still, on occasion, it feels good to be able to “pass”, but even when I don’t, other men regularly open doors for me, and I always thank them for doing so!


            1. I want to make it clear that by saying I didn’t care what the “genderist” crowd wants, I didn’t mean I don’t care about the rights or concerns of transgender people. I just don’t care about unreasonable political activism (by anyone) that blindly ignores matters that CAN have real and serious effects…and certainly one’s genetic sex can have medical implications, including, for instance, the need to be aware of the risk for prostate cancer, etc. however small that risk may be.

              Your political rights should be every bit as great as ANYONE else’s and you should have the right to call yourself whatever speaks the truth about your experience, and to live your life how you please as long as it’s not infringing on anyone else’s rights. And transgender people, as far as I know, are no more likely to do that than any other group.

              1. On the other hand, after going through HRT, the risk of cancers for transgender people don’t continue to match their “genetic sex” (apparently, after HRT, trans men have similar rates of breast cancer compared to cis men, and trans women have significantly lower rates of prostate cancer than cis males. You might need to scroll a bit, but these are two links about that)



    1. Last time I was in they had a new question, asked verbally, that was something along the lines of ‘do you have any bits you weren’t born with’ – which I thought was a nice way to inquire.

  12. Who would have thought that scientists and academics can be as insane as the Christian right?

    Perhaps humans are just herd animals and being an atheist does not make you immune to other irrational and Groupthink beliefs.

    1. I was just thinking the exact same thing. A large measure of my disdain for fundamentalists is their refusal to accept reality. No, I don’t “believe” in evolution; I ACCEPT evolution.
      It seems that Woke Leftists are no better.

    2. Or as a friend once remarked way back in 2001 or thereabouts: “you can go so far to the left that you end up on the right”.

  13. There’ve always been (rare) individuals who’ve been born legitimately intersex. There’ve also always been people who’ve suffered from gender dysphoria. And those folks are entitled to be taken seriously and treated fairly — much more fairly and seriously than they have been historically.

    But all this johnny-and-janey-come-lately boys-who-are-girls-who-are-sometime-boys-who-are-sometimes-girls stuff has the feel of a fad.

    1. “And those folks are entitled to be taken seriously”

      Depends what you mean by “seriously”.
      I regard gender dysphoria as a psychiatric condition and reassignment therapy might be appropriate or not.

      We take schizophrenics seriously and emphasize with their suffering, but we do not accept their delusions.

      “But all this johnny-and-janey-come-lately boys-who-are-girls-who-are-sometime-boys-who-are-sometimes-girls stuff has the feel of a fad”
      I agree, and they exhibit forms of personality disorders.

      1. Gender dysphoria is far from the only body dysphoria known to psychology, with people who feel like they “should be” blind staring at the sun and pouring bleach into their eyes, people who feel they should be paraplegic trying to get their limbs amputated, and all kinds of other fascinating – and tragic – phenomena.

        I don’t see a revulsion of one’s penis to be much different from a revulsion of one’s limbs or nose or vision. But the “trans” kind of body dysphoria is the only one we treat by actually cutting off the offending body parts as opposed to teaching them how to accept themselves. (Though plastic surgery does sometimes go too far as well, I think.)

        1. Not all trans women have a revulsion of their penises and get castrated like Skopzis. Some don’t do anything to their bodies — remember, it’s “the thought that counts.”

          1. It’s true that they now say you can be trans without having any gender dysphoria at all. To me it seems to almost pull the rug out from under the whole thing, because if it’s not based in gender dysphoria then what is there to empathize with? If you don’t actually suffer for being who you are, then I guess we don’t all have to go out of our way to accommodate your desire to be something else, eh? 😛

            1. I’d aver that Jessica Yaniv is a great example of someone being “trans without having any gender dysphoria at all” https://torontosun.com/news/national/balls-to-that-human-rights-hearing-in-b-c-trans-waxing-war. She’s sued women in Canada who give Brazilian waxes to females and Yaniv’s male-lady parts are intact. The operators of these salons refused to wax her balls, so Yaniv sued them for committing ‘hate crimes’, calls them transphobic bigots, and at least one proprietor of a waxing salon was driven out of business.

              Here’s one thread from Yaniv’s twitter feed: https://twitter.com/trustednerd/status/1132635928776675329?s=20. It’s simultaneously sad, pathetic, infuriating, and hilarious.

    2. It does have the feel of a fad but to say that can lead people to dismiss it as not serious, like pet rocks and hula hoops.

      It may be a fad but it’s a fad with serious and life altering consequences, especially when it comes to sex reassignment surgery and hormone treatments given to children.

  14. It fascinates me that the claim of gender fluidity is attributed exclusively, I think, to homo sapiens and no other creature. Has anyone had the chance to confront the gender fluid crowd with that question vis a vis evolution?

    Amazing how much like religious fundamentalists these individuals are…and in a sense, it makes sense as they are all authoritarians.

    “Biologically Male Runner To Compete In USA Women’s Olympic Trials”

    Sport’s Illustrated via Daily Caller


  15. A major reason why Iran is among the main countries for sex-reassignment is that religious authorities have decreed that if a man is caught having sex with another man, then they can either be punished or have a sex change. Same for women.

    It’s how clerics in Iran have resolved what they see as the problem of homosexuality.

  16. I spent the first forty years of my life in a closed-off ideological prison that denied the implications of evolutionary science. I’m not about to do that again just because I went from being a fundamentalist Christian to a liberal atheist.

    As I told one woke liberal friend a couple of years ago, if she can identify as male then I can identify as Louis XIV and request that she please address me as “Your Majesty.”

      1. Monsieur le Roi, as a friend, informally or, Louis XIV, par le grâce de dieu, Roi de France et de Navarre, I believe is the only proper way to speak to le Roi de France Louis XIV. Anything less is an insult.

  17. Obviously attraction to a mate of the opposite sex is a biological universal and requires no explanation. In humans and other mammals it is presumably genetically determined. However, I am curious as to possible mechanisms which could lead young children – long before erotic and emotional attraction becomes an obvious factor – to be convinced that they “really” belong to the gender different from their biological sex.

    1. “Obviously attraction to a mate of the opposite sex is a biological universal and requires no explanation. In humans and other mammals it is presumably genetically determined.”

      Your comment reminds me of the (perhaps not so curious) case of the current “Dear Prudence” at Slate, née Mallory Ortberg, female; then Mallory Daniel Ortberg; then Daniel Ortberg, now Daniel M. Lavery. He married Grace Lavery-Ortberg (an English prof. at UC Berkeley), née Joseph Lavery, male. Mallory became Daniel and Joseph became Grace and now they’re a happily married transheterosexual couple. See how it all works out just fine in the end! I am so confused but they’re not and I sincerely hope that they live happily ever after.

      Re your question about trans children, here’s an article on trans children from Spike! https://www.spiked-online.com/2020/02/07/the-making-of-trans-children/. I can’t comment on it since I’ve just begun to read it. But lots of stuff from a variety of perspectives on the Internet.

  18. There are zero intergradations of the sexes at the haploid phase of the human life cycle (gametes), and so the gametic sex binary is exactly strict. This is probably due to gametes having far fewer dimensions along which their phenotype can be influenced by developmental deviations, and any marked deviations that make it through resulting in loss of functionality. And so every single individual, whether they male, female, or intersex, is the product of a fusion of a well-defined male gamete and a well-defined female gamete. Zero exceptions.

    On the other hand, developmental intergradations in the adult stage are real (though rare) due to the higher dimensionality of adult phenotypes.

    That is to say I don’t quite see how one can equate ‘strong bimodality’ and ‘binary’ in the adult stage. Those aren’t synonyms, and “effective binary” sounds like declaring victory by terminological fiat. Why not just concede that binary is not the right word for the adult stage, and only use ‘strong bimodality’? The word ‘binary’ can continue to apply, in an exact sense, to the gametic phase. Such a view would continue to discount any notion that sex is not completely influenced by biology (as opposed to gender, where culture is added to the mix).

    1. I think along these same lines and for that reason think this is a good suggestion. Adults differ in lots of ways in terms of male and female oriented traits, including very likely differences in parts of the brain (this may be controversial but I think it is likely to be true). I suspect that there is also be variation in which parts of the body are more feminized or masculinized, which results in different combinations of more male and female type features. I think this might also address comment 20 by Raymond Cox: I suspect that which sex one identifies goes beyond just mating aspects and who one is attracted to sexually. It is not like children are genderless until sexual maturity: it would make sense for a brain to be programed to develop as a particular gender (sex) before sexual maturity.

  19. With the advancement of medicine, the ability by other means to have offspring and manipulate, to move body parts around, the hypo emphasis on individual rights and preferences, the biological imperative to the binary sex system is in redundancy, on a half life (as in, decaying into something else) flexible? and of course, albeit only for a portion of brains in the global population for now. How many hide this for cultural, deep personal constraints.
    The sex on a spectrum world is here to stay for the, what i think, reasons below.
    NS has ‘given’ humans a brain to be creative, expressive, original, an ability to dream, use virtual worlds and conjecture, make stuff up. To contain all that is problematic, as in keeping it real while having scope to move with it, coupled with the freedom to chase whatevèr it is that’s motivating your being in search for purpose… in some far off future, being human will not be what you or I, if we humans get a future, think of now.

  20. There is I think a sense in which it’s reasonable to deny that sex is a binary, and that’s when the philosophical definition of “binary” is used: “a conceptual hierarchy which is formed by taking a term with a dominant positive value and creating a subordinate value by negating the privileged qualities of the dominant term.” (Jane Clare Jones)

    That would include masculine/feminine; mind/body; reason/sensation, and so forth. Male and female aren’t binaries — they’re natural differences. The confusion of bimodal sex with the conceptual hierarchy of socially constructed gender leads the belief that denying that there are two sexes is going to “break the binary” and legitimize people behaving as they wish.

  21. Permanently harming children, or allowing them to hurt themselves, is child abuse. If consenting adults wish take drugs and have invasive surgeries that is their right, as much as I think they are mistaken and need therapy, instead. But to administer hormones, testosterone, or puberty inhibitors to preadolescent children is irreversible, and is nothing less than child abuse masquerading as “wokeness” on the part of the parents. It is inexcusable that doctors enable it, and unbelievable that the courts allow it.

    1. I suspect this will all become tragically clear in a few years when these children talk about how they made a mistake and wished that adults had guided them better.

    2. Do you allow teenagers to have abortions or other medical procedures without their parents’ consent? In Quebec (at least when I was a kid) one can get medical procedures without parental consent at 14.

  22. “A few species have “mating types” that encompass more “sexes”, but these are virtually nonexistent in vertebrates”.
    This reminds me of orangutans, where the males come in two types: the large fat-faced males, and the small males that resemble females. The latter practice rape (or something close to it).
    No, I did not infer that human transgender ‘women’ are all rapists.

  23. Those most vulnerable to sex denialism are children. When they’re taught that sex is grounded in identity instead of biology, sex categories can easily become conflated with regressive stereotypes of masculinity and femininity. Masculine girls and feminine boys may become confused about their own sex.

    This bit I like in particular. Instead of telling ‘non-conforming’ children they are wonderful and complete just as they are, we’re telling them they’re wrong-bodied.

  24. Masculinity and femininity are spectra. Feminine boys and masculine girls should be accepted and treated with respect, trying to change their sex to fit in a binary category doesn’t seem very woke, and isn’t it ironic?

  25. “sex in humans is bimodal: if you do a frequency plot with ‘sex’ on the X axis and ‘frequency of individuals conforming to that sex’ on the Y axis, you get a huge peak at ‘male’, another huge peak at ‘female’, and then a few tiny blips in between that conform to hermaphrodites or intersexes’

    With all due respect, Professor, I think you’re labouring under a serious misapprehension about the nature of population distributions.

    If you’re plotting a range of some variable on the X axis then you are, ipso facto, arguing that there’s a spectrum of values. And you are, in effect, asserting that 2 of those “values” are “male” & “female” with some other unspecified values that ALSO qualify as sexes: a spectrum of sexes, a veritable multitude of sexes. I rather doubt that’s your intent, but it sure looks to qualify as the effect.

    Analogously, consider a population distribution of heights for men & women with the range of heights on the X axis from, say, 120 cm to 220 cm with the frequency on the Y axis. And each of those points in the range is, in fact, a height in a continuous spectrum.

    Seems that what you’re more accurately referring to is, for example, a population distribution by karyotype, of which there are, maybe, some dozen or so possibilities in something of a discrete distribution. And in that case, you would, in fact, have two peaks on the XX (nominally female) and XY (nominally male) karyotypes – each of about 49% of the total population – with much smaller peaks on the other possibilities (0X, XXX, XXY, XYY, etc).

    Male and female are, by definition, based on the ability to produce sperm or ova, and therefore sex is, also by definition, binary.

    1. There is a spectrum of values: all eggs no sperm, all sperm no eggs, none of either, or a percentage mixture. It doesn’t have to be binary simply by definition. The fact that it is shows that sex is binary. Same with genitalia: penis, vagina, or some mixture.

      What a patronizing git you are. With all due respect, I don’t think you’ve thought hard about the issue.

  26. “Analogously, consider a population distribution of heights for men & women with the range of heights on the X axis from”

    How is this analogy relevant to sexual reproduction? Any half pregnant males?

  27. To be a bit more precise, biological sex in humans is bimodal: if you do a frequency plot with “sex” on the X axis and “frequency of individuals conforming to that sex” on the Y axis, you get a huge peak at “male”, another huge peak at “female”, and then a few tiny blips in between that conform to hermaphrodites or intersexes.

    Surely there are outliers who don’t lay between the two main peaks, and those who are closer to either or both peaks, but not in any easy sense a mixture between the two “end members”?
    Shrug : it’s not a big problem or a small problem ; it’s someone else’s problem.

    1. Are you asking if in humans two sperm could fuse to form a zygote? No… the cells would lack mitochondria. Two eggs? Also no, since fertilization by sperm is required for the completion of female meiosis. The latter phenomenon falls under the topic of ‘meiotic arrest’; in humans, and many other animals (e.g. fruit flies), oocytes don’t complete meiosis until after fusion with a sperm cell.

  28. Is there is good argument to delay hormonal/surgical intervention only until the mid-teens, as opposed to 26 years old when the brain is fully developed?

  29. Professor Coyne,

    I have admired your work and writings for many years. After learning of the WSJ article, a Google search revealed your response and commentary.

    I am a transgender female, age 52. I have long hair that goes down to the middle of my back, I shave my legs daily (well, almost), and, on occasion, I wear full skirts, in public, and even find them to be somewhat more comfortable, physically, than pants.

    I guess, “What does Society want from me?” I regularly face discrimination in work (I am self-employed because of this), am treated rudely by some convenience store associates (yesterday, one gave a loud belch as I was walking out the door), regularly fear violence in the men’s restroom, and even get some dirty looks from the Amish when I travel outside of my town.

    I just want to live my life and be left alone, with my wife and our 5 adorable children.



    1. Thank you for writing, and I am terribly sorry that you are subject to that kind of rudeness. There is no excuse for it. I wish you the best of luck and hope that people will realize that that kind of behavior is unconscionable.

  30. Think I’d agree with this point of yours, though with maybe a different emphasis:

    So IF we defined “sex” as functional reproductive type, THEN it’s strictly binary.

    Along the same line, the Australian feminist philosopher Holly Lawford-Smith had an interesting Medium article (“Is it possible to change sex?”) in which she said:

    Whenever you chat to a biologist about what they understand ‘sex’ to be – and I have chatted to a few – they tend to talk about large and small gametes. Human sexual reproduction proceeds through the combination of sex cells of two different sizes (this is known as anisogamy): small gametes (sperm) and large gametes (ova). Males produce sperm, and females produce eggs. Almost no definitions that we give in philosophy have a single necessary condition, but sex is one of the few instances where such a definition works well. If a human individual produces sperm then he’s male, and if a human individual produces ova then she’s female.

    Not knowing that many biologists, I’d wonder how prevalent that “understanding” is, although it certainly seems plausible, and a useful perspective.

    But I think that “single necessary condition” of Lawford-Smith’s highlights the fact that many of us tend to conflate denotations and connotations – as with different interpretations of the word “woman”. And similarly conflate the “necessary conditions” for being of a “functional reproductive type” (based on the two different gamete types) with all of the many traits that might correlate with those types– everything from chromosomes to genitalia to heights to hair colours to psychology.

    Although it is unfortunate that such conflation often causes a lot of unnecessary misunderstanding and animosity. And Chivers’ recent article on Dawkins and the “decoupling controversy” is maybe relevant to that as well.

  31. Would be interesting, likely quite informative and illuminating, to hear Jerry’s views on this latest and very well documented thread from Colin Wright:


    Particularly as Emma Hilton has explicitly asserted, with some justification and in the same thread, that:

    To assert “bimodality” is to necessarily evoke a spectrum along which that bimodal distribution can be plotted.

    Though I’m not sure she’s entirely correct as the x-axis could consist of two and only two discrete values, i.e., male and female.

    But she has also expressed an interest in hearing Jerry’s reasoning for his position.

Leave a Reply