I didn’t delve into is in this piece, but males have advantages in lean body mass, lung size and function, and heart size and function before puberty. A great place to start looking into this in more detail is the 2005 paper by Eiberg showing that when 6-7 year old boys and girls engage in the same amount of physical activity the boys have a higher VO2max and more lean body mass.

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Sep 2, 2023Liked by Gregory Brown

>" . . .transgender identified males (i.e., “transgirls” and “transwomen”) should not be allowed to participate in the female sports category before or after puberty even when puberty blockers are used."

Puberty blockers ought not to be used in anyone (except for kids with precocious puberty), so this particular issue ought to be moot. No boys in girls' sports. Period.

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Sep 1, 2023Liked by Colin Wright, Gregory Brown

This presentation is really excellent and fills the gap in the general public knowledge database. In short, before puberty, boys and girls really do differ one from another! Thanks to the author.

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Considering that a male fetus cranks out testosterone like crazy, it would be crazy to think male and female children aren’t different on body features which are testosterone driven.

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And not just "body features", but in many psychological traits that one might reasonably argue constitute the bulk of gendered traits, i.e., those typically masculine or feminine.

Given that you, if I'm not mistaken, apparently have some statistics under your belt, you might want to take an gander at an article that Colin co-authored that seems to provide substantial evidence of "sexually dimorphism" in behaviours and personalities -- "gender" in a nutshell:


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I remember reading it some time back, thanks. If you can hold your seatbelt I have a slightly different view.

I love having my cock sucked, and I like sucking cock. Part of that behavior may seem overlap with behaviors women have; part is impossible to overlap. But there is nothing feminine about the behavior and feelings. Any impression that my view of cock is “gender-atypical” or overlaps with women is a complete misconception . It is categorically a male behavior.

I think men and women have a range of biologically determined, sex linked behaviors which are simply non-commensurate. Believing they are measurably comparable is a word I can’t express, something like anthropomorphizing animal behaviors. Saying a man who is nurturing is exhibiting a female behavior is nonsensical, same in reverse with aggression. Classically the expression is apples and oranges.

Men don’t have female behaviors; any behavior a man has is by definition a male behavior.

That’s why there’s no wrong brain wrong body.

Similarly, not liking one’s own sex is not the same as “being” the other sex, or “feeling like” the other sex. But this is a lot of tapping on my iPhone...

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Apart from the questionable propriety of regaling us with your sexual peccadillos and predilections, I think you seriously misunderstand that 4th Wave Now article, and, in particular, the plot therein of "joint probability distributions" of "personality profiles".

Which is probably a large part of the reason why you seem so "reluctant" to consider DEFINING "gender" as sexually dimorphic personalities and personality types -- at least to a first approximation -- as many credible sources DO.

But more particularly, I doubt anyone is seriously denying that each sex has some more or less unique "behaviours and feelings" -- rather doubt any man (adult human male) has ever gestated and given birth to a fetus and experienced the feelings related thereto.

However, the point of that joint probability distribution is that some behaviours -- many behaviours in fact -- are more common in one sex than in the other, is that they correlate more with one sex than the other, is that they are more stereotypically masculine or feminine.

Consider a somewhat simpler example, a comparison, a joint probability distribution of agreeableness by sex:


Women are -- ON AVERAGE -- somewhat more agreeable than men -- an average of about 4.1 versus 3.9. But agreeableness -- as one of the "Big Five" personality traits -- is NOT an intrinsic feature of either men or women, at any level in that range (1 to 5). At each level there are going to be more women than men or vice versa, but still not exclusive to one sex or the other. That, as you put it, a man exhibits a high level of "very agreeable behaviour" -- say, 4.7 -- does not in any way mean that he is a woman and in urgent need of "sex-reassignment surgery". All it means is that he has an atypical personality trait, that he's somewhat more feminine than the bulk of his cohort, that, on that one axis of a multi-dimensional "gender spectrum", he has a more feminine gender.

But that's one of the main reasons why I've been pushing for precise definitions for both "sex" and "gender", and for the idea that they're two entirely different kettles of fish: reproductive abilities, versus psychological and behavioural traits, respectively. You apparently seem to think that any and all behaviours that a man exhibits is intrinsic to all males, that no woman could ever possibly exhibit it too. When you say "male behaviour", all that means is the "behaviour OF males" or typical of males, not that it is the defining trait for males. Also why I also emphasize that, by standard biological definitions for the sexes, the ONLY defining traits, the only ones that are the "necessary and sufficient conditions" to qualify as males and females is the type of gamete being produced.

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Women and Pigs also have traits of agreeableness (I’m fond of Charlotte’s Web) but nobody would say there exists axis on where one side Feminine and one side there are Porcine traits, and discuss the overlap. Substituting “Man” for “Pig” simply masks the nonsensical nature of saying Men may have “Feminine” traits. Men and Women have human traits. There are some features of men and women unique to each sex which are incommensurate. If a man is “agreeable” or “nurturing” it is a human trait, by definition, neither masculine nor feminine, since both men and women have those traits. That’s why I reject the concept of “sex-atypical” traits which are in reality common to both male and female. (I refuse to use the word gender.) If a man likes cocksucking ( I use sex to be jarring ), enjoying cocksucking is categorically a masculine trait. “Gender” models would say it’s gender atypical. “Sex atypical” would be a man worrying about menstrual cramps, or a women concerned and embarrassed about a prostate...

It’s probably a point of simple disagreement. Some boys like rough and tumble play. Some don’t. Some girls do. Where I disagree is saying “rough and tumble” is masculine, and saying some girls have “masculine behaviors.” I don’t think you can measure dimensions of masculinity and femininity in a single person, and they are not the two ends of a continuous single axis. That creates a false view of traits being in opposition, or complementarity.


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Sufeitzy: "... simply masks the nonsensical nature of saying Men may have 'Feminine' traits ..."

Maybe you're biased ...

Sufeitzy: "If a man is 'agreeable' or 'nurturing' it is a human trait, by definition, neither masculine nor feminine, since both men and women have those traits. ..."

Sure, those are "human traits". But still think you're missing the point, or maybe you simply don't want to entertain it. The fact of the matter is that, as those joint probability distributions indicate, many traits or aptitudes are more common in one sex than in the other:

Wikipedia: "In particular, studies have shown female subjects performing better on tasks related to verbal ability, and males performing better on tasks related to rotation of objects in space, often categorized as spatial ability."


Sufeitzy: "... why I reject the concept of 'sex-atypical' traits which are in reality common to both male and female. ..."

Then you're rejecting the facts that there is some fairly credible evidence of significant differences in frequencies and magnitudes.

Sufeitzy: "... I use sex to be jarring ..."

Classy ... 🙄

Sufeitzy: "... Some boys like rough and tumble play. Some don’t. Some girls do."

Again the question and fact is different frequencies and levels in each sex. Which you apparently refuse to consider the evidence for.

Sufeitzy: "... I don’t think you can measure dimensions of masculinity and femininity in a single person."

Every one of the, probably, several dozen traits measured in that article by Colin and Company would seem to refute, rather resoundingly, that "conjecture" ...

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Sep 4, 2023·edited Sep 4, 2023

As far as sex based differences go those of females are usually considered inferior, but that might be just in the eye of the beholder. In fact, surveys of the public show that most people believe that male doctors are superior practitioners to women doctors.


If male doctors were more like female doctors, 32,000 fewer deaths would occur annually, new research suggests. The study, published in the journal JAMA International Medicine, included more than 58,000 physicians who treat Medicare patients.

2023 Guardian

Patients have better outcomes with female surgeons, studies find.

Differences in technique, speed and risk-taking suggested as reasons for surgery by men leading to more problems

Ian Sample Science editor

Wed 30 Aug 2023 11.00 EDT

People who are operated on by female surgeons are less likely to experience complications and need follow-up care than when males wield the scalpel, according to two major studies that suggest male surgeons have important lessons to learn.

Doctors in Canada and Sweden reviewed more than 1m patient records from two separate medical registers. The records suggest that female surgeons tend to operate more slowly and may achieve better results by taking their time in the operating theatre.

Dr Christopher Wallis, who led one of the studies at Mount Sinai hospital in Toronto, said the findings should prompt male surgeons to reflect on their approach to surgery and learn from female colleagues for the benefit of their patients. “As a male surgeon, I think these data should cause me and my colleagues to pause and consider why this may be,” he said.

A second study of 150,000 patients in Sweden, also published in Jama Surgery, paints a similar picture. Dr My Blohm and colleagues at the Karolinska Institute in Stockholm reviewed patient outcomes after surgery to remove the gallbladder. They found that patients treated by female surgeons suffered fewer complications and had shorter hospital stays than those treated by men. The female surgeons operated more slowly than their male colleagues and were less likely to switch from keyhole to open surgery during an operation were lower than those of male physicians.

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I remember reading, more than a few decades ago, a study of the electronics assembly industry that found that hiring women for those tasks was the better bet since they tended, on average, to have greater manual dexterity.

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Well, OK, but what if women medical-school grads don't want to go into surgery and go into family practice and primary-care pediatrics instead? Even though those disciplines don't pay very well, they allow more predictable time at home with children with less night call that involves coming into the hospital at 3 a.m. to save lives.

The women who do go into surgery are a highly selected group. Being the best of the best, their average competence may well be higher than the average of the men who go into it. You can't with a wave of your hand conjure up all the female surgeons that you'd like to have. They also earn less per hour than male surgeons, probably because they do take longer to do each case as you suggest.

The message from these studies, which I think you do describe accurately, is that, as Dr. Wallis says, male surgeons could reflect on what it is that female surgeons do differently. Working more slowly is not likely to be generally popular though. Even Canadian hospitals, which don't get paid per case, only the surgeon does, can't really afford to put fewer patients through the ORs in a year. The Ministry of Health will cut their operating budgets if they do fewer operations at a time when hospitals are trying to catch up with the enormous backlog from when non-emergency surgery was cancelled for two years during the pandemic.

Another female difference from the Wallis study may be that female surgeons are more astute to subtle changes in the post-operative condition of, especially female patients, reported to them by nurses. They may therefore "rescue" patients sooner and prevent serious deterioration. But again, the trailblazers are always better than the group that comes after them.

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The difference in outcomes is a social construct!

Ok, even though I can't help saying that in a Francis Aaron rap voice, I am actually semi-serious. If you're mostly looking at the medallists and record holders, don't you need to start by accounting for participation rates?

If there was a measure in which boys and girls were equally distributed, but you sampled many more boys than girls, your results would show many more boys than girls at both tails of the distribution. So this hypothesis hasn't been ruled out as the cause.

And participation rate differences could be caused by social factors. Parents might be more likely to encourage boys into sports than girls. Children might be aware that professional sport is mostly a male persuit, leading girls to be less motivated to participate than boys. (Or, of course, participation rate differences could also be caused by biological factors affecting the brain; girls could just be less interested in this stuff!)

And that's not all. You might actually be able to account for participation rate differences using statistical methods. But it might not be enough to just say "how many kids of each sex participate in this particular sport?". You might have to find out how many hours each child spends training. If boys train more than girls, again, you've left the door open to social factors as the cause.

And even if you do everything you can with stastics, couldn't there still be factors that would be extremely difficult to rule out? Such as parents pressuring boys more than girls, or simply being less likely to frequently say things like "it's only a game", to boys than to girls. And boys might 'want it more' - perhaps due to the social factor that is the embarassment of being beaten by girls. Or perhaps due, again, to awareness of better career prospects. (Or perhaps, again, biological factors affecting the brain rather than the body.)

Still, after all that, given the uncertainties, the presumption for the sake of policymaking should probably be that yes, there is an inherent physical advantage. And perhaps the non-inherent advantages need to be dealt with anyway. So just keep things as they are!

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In my faux voice, “you need to get out more”. In the European countries cited the social sex-focused “sports” dynamic you cited doesn’t exist in remotely the same form as the US. Exercise in children, in Saxon countries which I have lived in, js seen as part of health, not a stepping stone to organized competitive sports. There is no little league in Bonn, Den Haag or Copenhagen. Furthermore the acculturation of sex behaviors in countries cited is also quite different.

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There's another reason for excluding prepubescent "trans girls" from girls'-only sports and "trans boys" from boys'-only sports. It is that trans girls aren't girls and trans boys aren't boys.

In fact, there's a strong likelihood that individuals claiming to be trans girls and trans boys aren't even trans. That's because the gender identity indoctrination many children are exposed to in school and elsewhere may well be teaching them how to appear trans and motivating them to claim a spurious trans identity. The conventional wisdom outside the gender-identity bubble is that most youth who are gender nonconforing or who have gender dsyphoria will desist during adolescence.

Assuming for the sake of argument that there is such a thing as a trans kid, there is no way today to separate the minuscule number of children who would be best served by transitioning socially from the cis kids who have been swept up in the trans craze. That's because the medical and mental health establishments will not countenance a protocol that includes assessing the validity of a person's claim to a trans identity, be they a minor or an adult.

The longer a trans kid participated on the single-sex team that corresponds with their gender identity, the worse the consequences would be for the athlete and the gender critical movement of a sex-based team reassignment at puberty. Even it it was made clear to the child at the outset that they would have to switch sides when the hormones kick in and play with youth of the same biological sex, he or she might find it impossible to adjust to the change because of the cultural and social differences between boys' and girls' teams. Trans rights activists would be apoplectic at the sheer "transphobia" of it all. The contingent that wasn't racing to seek an injunction would be knocking down the doors of elected officials seeking legislation to block the practice.

That is why the best approach is to be faithful to biological and social reality and require that all minor athletes play with members of the same biological sex regardless of age to the extent permitted by law. By the way, the difference between sex and the law is that you can actually change the latter.

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Yet another reason to not comingle is to protect the privacy of both girls and boys from ogling and embarrassment.

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Thank you so much for this, Dr. Brown.

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