[lynndotpy]

This might be true if the Olympics were exclusively classifying the 23rd chromosomes, and nothing but.

Leave aside the fact that very few of us here have actually tested our 23rd chromosome. Historically, the Olympics have not been (and are not) strictly chromosomal. The 2023 testosterone suppression decision requirements has exclusively impacted cis women, for one example.

Humans are biologically dimorphic in the same way winters are usually cold and summers are usually hot.

[EA-3167]

I would say that humans are sexually dimorphic in the same way that humans are bipeds. if you attempted to make a serious argument that limb agenesis implies that we’re a variable-limbed species it would be obfuscating rather than illuminating.

[lynndotpy]

No, that is not a good analogy at all. It's so poor an analogy that it's challenging to interpret this comment generously. I think you might be arguing facetiously to make a different rhetoric point than the literal content of your post, bot I will respond to your text literally.

Humans have a wide variety of biological variation in metrics we think of as linked to "biological sex" and those metrics are accessibly mutable. Even within the Olympics, the natural variation of these metrics within cis women is a famous topic of debate (Imane Khelif, Caster Semenya, etc.)

Bipedalism is something which varies very rarely and is especially not accessibly mutable.

[zahlman]

> Humans have a wide variety of biological variation in metrics we think of as linked to "biological sex"

What is the total prevalence of all conditions medically recognized as intersex?

> and those metrics are accessibly mutable.

What is that even supposed to mean?

[lynndotpy]

> What is the total prevalence of all conditions medically recognized as intersex?

Not all biological variation is classified as intersex.

> What is that even supposed to mean?

You can change a lot of your 'secondary sex characteristics' intentionally. This is much easier than removing a limb, and even easier than adding a limb.

[zahlman]

> Not all biological variation is classified as intersex.

Okay, but other biological variation is clearly not relevant to the discussion.

[lynndotpy]

No, I am specifically talking about biological variation in sex characteristics. This is common, and it's not surprising if someone is within the range of "the opposite sex" for one or several sex characteristics.

There are men under 5'4", women taller than 5'9", women with high testosterone, men with low testosterone, men with breast tissue, etc.

[NeutralCrane]

> Bipedalism is something which varies very rarely and is especially not accessibly mutable.

This would apply to sex chromosomes as well

[lynndotpy]

So? It would apply to sex chromosomes and only sex chromosomes, which is just one observed sex characteristic.

We are talking about sexual dimorphism and secondary sex characteristics.

Humans were understood to be sexually dimorphic before we discovered sex chromosomes in 1905, and we usually label our babies with a biological sex without the aid of consumer genetic testing.

[badc0ffee]

I have a lot of sympathy for Imane Khelif and Caster Semenya, as they were assigned female at birth and raised as girls, and they want to compete with women. But I don't know if there's a case to be made that they're biologically female.

They have XY chromosomes, internal testes, a male testosterone level, and male muscle development. They have the SRY gene that the IOC is testing for, and are not one of the exceptions. Regardless of the fact that their DSD (5-ARD) results in no penis.

To be clear, I'm not saying they should start living life as men. But describing their situation as the natural variation of cis women is simplistic and not accurate.

[lynndotpy]

For starters, I can't find any credible source saying they have XY chromosomes or internal testes.

Further, they are women, and therefore their testosterone levels and muscle development are female.

This just gets to a ludicrous place. These are women who are simply identifiable as so. Anyone throughout history would have identified them as so. Their biological metrics are within the variation of cis women, because they are cis women.

[badc0ffee]

Caster Semenya: https://www.bbc.com/sport/athletics/67367157

[lynndotpy]

This is fair, I didn't know about this, but this doesn't appear to be the case for Imane Khelif.

Either way, my point still stands. These women are women, would have been recognized as such by anyone throughout history, and it's simply the case that some women are born with XY chromosomes and testes.

[enragedcacti]

99.8% of all matter by count is either hydrogen or helium, are atoms dimorphic?

[brainwad]

If you're a cosmologist ;) usually they talk of 3 elements though - H, He and "metal".

[EA-3167]

That’s a very fun way to think about it, but it’s far more effective in a semantic debate than a serious one. I also don’t for a minute believe that the goal here is some broader reform of how the world talks about statistical distributions.

I’d rather not have discussions in bad faith.

[enragedcacti]

It was intended in good faith, to make the point that rarity alone is not a good metric for salience. In my experience, most trans people have no problem with the statement "humans are sexually dimorphic" in a biology context. They (and I) have issue with it when its used in a debate to say "Humans are sexually dimorphic (and therefore trans and intersex people are irrelevant/shouldn't be accommodated/don't exist)". In the context of sports, it is definitely relevant that there are many edge cases and substantial overlap in the distribution of phenotypes between AFAB and AMAB people.

Coming back around to the olympics: I agree that humans are bipedal, but that has no bearing on the fact that the Olympic committee should take great care to create rules and categories for paralympic athletes. I think there's a lot of room for reasonable people to disagree without dismissing the complexity that comes from organizing across 8 billion people.

[zahlman]

> They (and I) have issue with it when its used in a debate to say "Humans are sexually dimorphic (and therefore trans and intersex people are irrelevant/shouldn't be accommodated/don't exist)".

But that is not being said here, just as in every other time the discussion of sex segregation in sports comes up; and just as in every other time, people simply pretend in bad faith that such things are being asserted.

> I agree that humans are bipedal, but that has no bearing on the fact that the Olympic committee should take great care to create rules and categories for paralympic athletes.

Sure. Which is why they do, and nobody has a problem with it.

Go take a survey of the people opposed to transgender women competing in women's Olympic sports, and see what they think of having a separate category for transgender athletes. Or even separate categories for transgender men and transgender women. I'd wager the large majority have no problem with that. (They might at most be concerned about disproportionate airtime being given to sport events that relatively few people qualify for and relatively few people are especially interested in.)

[EA-3167]

Speaking for myself I believe that trans people and non-binary people should be accommodated, but there’s a contextual limit. When it comes to equal protection, employment, healthcare, medical access, bathrooms and a dozen other issues it’s a no-brainer in favor of accommodating people.

Ironically the sports divide is probably the single area where having some physical advantages isn’t a bonus. It’s also near and dear to the hearts of billions, and such a terrible hill to die on. Ideally the solution would be a league like the Paralympic competitions, but high level athletes are rare, trans people are relatively rare, and two overlapping are incredibly rare. To make such a league would be a farce that couldn’t hope to succeed.

[lynndotpy]

In the Olympics, it appears trans athletes are still a minority among the group of athletes who are excluded because of sex characteristics. Most of the athletes impacted by the ever-stricter testosterone limits in the Olympics are cis women. Such a league would include cisgender former Olympic athletes who had to undergo forms of HRT in order to qualify.

When discussing trans people in sports, the most salient contexts aren't elite sports championships like the Olympics. "Sports" is also done recreationally and is often considered a normal part of ones childhood upbringing. On the topic of trans people, the question "can my child play this sport with their friends"?

[lynndotpy]

To add to this, I want to stress on the point of rarity. Variations within sex metrics are not the uncommon fringe case people make it out to be, they're actually common and expected.

Within biology, we'd see a number of metrics (like height) which would usually appear bimodal (like two bell curves added together). We might identify at least two latent variables here: A real-number 'age' (which can be observed) and a binary 'sex' (not directly observed). But it's worth stressing that these implied underlying curves overlap, and any given metric is not strictly correlated with the others. (Commonly, one might be on the lower end of some distributions and the higher ends of others. Someone can be 5'3" tall, have red hair, and a high body-fat percentage while also having testicles, XY chromosomes, and dying at the age of 62.) (We should also note that the 23rd chromosome just another observed variable, starting after ~1900.)

Some causes of variation that we know about are fraternal birth order, or endocrine-disrupting chemicals like PFAS, conditions like PCOS, etc.

Case in point are all the cis women who are impacted by the ever-stricter testosterone guidelines in the Olympics. Further is the effect of fraternal birth order, or the endocrine-disrupting chemicals like PFAS, or the intentional introduction of hormones and hormone blockers. (If certain industries are to be believed, soy milk has a similar effect.) These are all variations and things which impact what we understand as "biological sex".

Folk gender theorists tend to consider sexuality, identity, biology, and expression as orthogonal axes. But these are clearly also correlated among people. (Stretching the definition of "correlated" to include qualitative metrics like 'expression' using the usual methods.)

An information-theoretic framework would inform well an "optimal" way to talk about this, using a one-bit string for most people and increasingly more bits when more information is needed. This is roughly how people already talk.

[zahlman]

If it were possible for us to exist (and thus consider the question) in the absence of the other atoms, and if those other atoms overwhelmingly (somehow) had a number of nucleons between 1 and 2, then the analogy might plausibly make sense.

[zahlman]

> Leave aside the fact that very few of us here have actually tested our 23rd chromosome.

When people do submit to such testing, how commonly are the results other than they expected?

[crote]

More often than you'd think! You can easily go your entire life without knowing. It is not uncommon for the first hint to be that a couple is having trouble conceiving.

[zahlman]

> More often than you'd think!

Perhaps not, given the selection effect.

> You can easily go your entire life without knowing.

Sure, since we already established that the tests are usually not done at all.

An overwhelming majority of people (at least among those who have a basic understanding of the underlying science) could, however, guess correctly about themselves.

The combined prevalence of all intersex conditions is simply not that high.