It is a statement of an obvious truth. It does not need to be "brave". If you find the point true but irrelevant then you would be better off not acknowledging it in the first place.
It's not brave, it is an important topic. Hundreds of thousands of scientific studies over the last two centuries excluded female subjects because it was too hard to predict their wild female hormones or some other ghastly excuse.
Biological sex differences do have important, medically relevant, and poorly understood impacts on health across the lifespan, and unfortunately the field is in its infancy.
> Sexual dimorphism is real and has important medical implications.
I'm guessing (well, hoping) that everyone agrees that the male/female distinction is medically relevant. E.g., I'd get more from a visit to a urologist than to a gynecologist.
I think there's less agreement about the "di" part of "dimorphism". Obviously most humans fall pretty squarely into the "male" vs. "female" categories, but there's less agreement about there being precisely two, clearly delineated categories.
Some examples:
- hermaphrodites
- conjoined twins with different genders (insanely rare, IIUC)
- non-heterosexuals and transgender people, to the extent that those characteristics indicate underlying physiological differences
Like basically every biological category, the borders of biological sex are blurred. But the vast, vast majority of animals slot into one or the other category. So it’s pretty reasonable to accept the GP’s premise - that sexual dimorphism is real. The exceptions prove the rule.
> non-heterosexuals and transgender
The discussion here is about biological sex and its medical implications. People who change their gender, or exhibit traits of the opposite gender, aren’t relevant to this conversation.
Edit: commenters below me make some good points that I didn’t consider when writing this. I slightly regret this comment now, but can’t delete it at this point. e.g: the fact that transgender people are relevant to this debate because of HRT, which is true, I didn’t think of that.
> The discussion here is about biological sex and its medical implications. People who change their gender, or exhibit traits of the opposite gender, aren’t relevant to this conversation.
This seems obviously false. If the link is based around sex hormones, as an example, then being on HRT clearly changes your risk.
People who change their gender, or exhibit traits of the opposite gender, aren’t relevant to this conversation.
Well, they can be – treatment with e.g. hormone therapy has obvious physiological impacts with subsequent influence on the effect of other medical treatments.
Nobody serious doubts that there exist sex-linked physiological characteristics; in reality, the original statement that "sexual dimorphism is real" isn't intended to share knowledge, but a subtle signal about something else.
> The discussion here is about biological sex and its medical implications. People who change their gender, or exhibit traits of the opposite gender, aren’t relevant to this conversation.
“Biological sex” is a catchall label for a wide basket of traits that tends to cluster in two large groups. Almost anything attributed to it is, on further examination, really a result of some more specific subset of those traits, which may overlap those certain individuals exhibit that are not stereotypical for their birth gender for whatever reason. So, yes, those differences matter.
Which demonstrates the important of distinguishing gender identity from biological sex (i.e: woman from female, man from male).
When deciding what pronoun to use, biological sex clearly doesn't matter, when talking to a doctor, it may well matter. We can use the appropriate thing at the appropriate time, just as we do with, say, an adopted child, where most of the time you don't need to distinguish, but when it comes to inheritable disease it clearly matters. Likewise, saying "that female over there" when talking about a trans man is utterly useless to me because it doesn't help me identify them without pre-existing knowledge. Man/woman referring to gender identity clearly makes sense for casual conversation, someone's biological sex is none of your business in most cases.
Of course, our increased understanding also says that dimorphism is an oversimplification: the reality is that sexual traits are varied and it is much more of a spectrum, and better understanding of this medically should lead to more personalised medicine that is more effective.
This is especially true when it comes to trans people, if the issue is, for example, linked to oestrogen, then HRT can be more relevant than the chromosomes someone has.
This is clearly not very useful, or reasonable. People's biological sex is none of your business, so using it when talking about them is not viable. If you see someone who is presenting as a woman, calling them a man because you happen to know they are trans isn't useful to anyone you are communicating with, and it's reminding them of something they'd rather not be bought to the forefront, just as with specifying someone is adopted—it's irrelevant to the conversation in 99% of cases.
> If we muddy these words to mean gender, then no one will understand what anyone is saying when talking about health, or sexual orientation, etc.
We have trans/cis, male/female, and "biological sex"/"gender identity" to distinguish. We manage to be just fine referring to both biological and adoptive parents as just "parents" and we can still specify where necessary.
> If we are talking about a transman, then you can talk about their sex by referring to them as a woman and as a female. Their gender identity is "transman". Even if they appear to look like a man, their sex has not changed.
Transman isn't a word, it's incorrect. Trans men are men who are trans, in contrast to cis men. Turning it into a single word would be like calling someone a tallman.
No one ever claimed their sex changed, their gender identity is distinct from their sex, that was very much the point.
is there any case where it does make sense to take gender "preference" into account? besides pronouns?
seems to me that those who insist that gender and sex are distinct also heavily imply that biological sex is mostly meaningless, so its unclear what they actually expect anyone to care about
> seems to me that those who insist that gender and sex are distinct also heavily imply that biological sex is mostly meaningless
Gender (either socially ascribed or gender identity, though those two can differ from each other) and biological sex are objectively different things.
Most people who value gender identity rather than the particular indicia of biological sex other people prefer as a basis of socially ascribed gender generally view biological sex as a multidimensional space which includes (among other things, some of which are mutable) gender identity, not a simple binary (even if the distribution may be strongly bimodal.)
> its unclear what they actually expect anyone to care about
Generally, gender identity rather than other factors to the extent that society divides people up by ascribed genders. But also generally a lot less gender segregation, and especially strict binary gender segregation, at all, and when distinctions need to be made to which particular sex- and/or gender-stereotyped traits are relevant, to make distinctions on the particular relevant trait rather than by stereotypical association.
> also heavily imply that biological sex is mostly meaningless
This is a puzzling statement to me. The whole concept of being trans requires that there is a distinction between gender identity and biological sex. If the latter didn't matter at all, being trans wouldn't exist. If anything, trans people would surely be the most aware of biological sex and it's impact on them, as they are not happy with it?
To me, it's like saying an adoptive parent is trying to imply biological parenthood is meaningless. Surely those who wished to have biological children but could not and adopt instead are often the people most sharply aware of it?
Unfortunately "biological sex" becomes extremely nebulous when you take into account years of cross-sex hormone treatment. Many of the genes that control sexually dimorphic traits are activated by sex hormones. Someone who's been taking exogenous hormones for years will have a very different medical profile than someone who has not.
If it's a subject that makes you uncomfortable then don't read about it. I wouldn't expect people discussing human sexual dimorphism to alter their discussion to accommodate gender dysphoria any more than I'd expect entomologists to alter their discussion about spiders to accommodate my arachnophobia. You do raise the question of whether the potential effects of the hormone alterations attending gender transition on the gut microbiome have been studied. I'd be curious about those results.
I understand why you are saying this, but one should not be made uncomfortable by reality. That may be the case for some, but it is easier to change mindset than it is to alter reality.
I mean, the first step is actually determining what the sex-specific mechanism is.
Microbes in your gut generally aren't checking sex chromosomes. They interact with sex hormones (see Rizzetto et al., 2018 cited in the paper for this very thing) which often reflect sex chromosomes.
Hormone levels or response may not match what is typical of sex chromosomes for a number of reasons including: 46XY women (androgen insensitivity), trans people on HRT, women post-menopause, and sometimes cancer treatment.
IMO it would be less alienating and lead to better health outcomes for everyone if we talked more about testosterone-dominant or estrogen-dominant endocrine systems (or other systems as appropriate).
Also whether dimorphic effects are a result of a one-shot process (e.g. grow testes or ovaries, grow breasts), or a recurring process (hormone levels triggering lactation, sweat patterns).
Basically, transgender brain has some sex-differences that resembles the gender that the person identifies as, and that is before hormone therapies has been applied. If they did such study on antibiotics then you would likely have to do multiple ones, including if the person have taken hormones before or after puberty.
Root causes here probably aren't about chromosomes but about hormone levels so something else that is more about amount of N. That's how you look at things without making it about "male" 9r "female" (since, to use hormones as an example, those vary between individuals and within an individual over a life).
I'm trans and I'd generally like more follow up studies to determine if various medically-important sex-dimorphic factors are downstream of endocrine differences. Otherwise I won't know which profile fits me better and I might get worse medical outcomes.
Personally, I much prefer to learn about sex dimorphism in analytical/academic contexts, rather than in emotional/social ones. I actively seek out and read papers like this in my free time.
Adopted parents/children often feel uncomfortable being reminded of the "truth" of their biological parenthood. While we should absolutely focus on being accepting and treating adoption as just as valid as biological parenthood (because it is, just as with gender identity), it would also be cruel and unreasonable to intentionally go our of your way to point out someone's lack of a biological relationship with their parents when there was no need for it and you know it causes them to be upset.
Largely, this is a problem with society for telling them they are lesser for that, and people having treated them badly because of that, which they have then internalised as shame or a feeling of being less than.
In the adoption example, I would argue that it is not a product of society, but just very present in society. I don't have data to back this up, but kids seem to be innately cruel about things like a peer being adopted, and I don't think it was programmed into them from society.
If there is an innate cruelty in our children that we allow to fester and allow them to apply in our society, rather than teaching them against it, then that is absolutely a product and failing of it.
We are pretty advanced, we can do more than throw our hands up in the air and say "that's how it is" when faced with problems. If we choose not to, it is exactly that: a choice.
I'm not throwing up my hands (if you were suggesting that) because I still think kids should be socialized. I would agree that society should socialize it out of them, and if they don't, it is a failing of society, but I still don't agree it is a product, because product implies origin. It's more interesting to me to understand why the origin exists.
It's nothing special about being adopted, kids can be brutal about anything unique/rare difference an individual has from the group. (Only transkid bullied, only poor kid bullied, only redhead bullied, say you like country when everyone else say rap or vis versa, etc) kids can be brutal and irrational in groups for sure. And if you follow politics you notice adults aren't much better ether.
Not trans myself, but I can tell you from my personal experience that very few people are actually uncomfortable or alienated by topics like this – that's usually more of a bit of fiction belonging to the "you can't even say WOMAN any more" genre.
In contrast, trans people are usually extremely aware of their biology and related medical requirements - to a greater extent than many others. Like any other topic that might be sensitive, the best approach is to be respectful, accurate, and specific. For example, don't do the thing up-thread of banging on about how "gender isn't relevant to this conversation" without really having that insight.
So, research into the impact of biological sex on medication, and similar, doesn't really seem alienating to me. Despite the existence of trans people, there are obviously two main categories that people fall into in a medical sense.
That said, I do think it would be a mistake to assume that the conclusions of any research into biological sex can be directly extrapolated to trans people. If we know that the relevant mechanism is hormones or chromosomes we may be able to predict effects on trans people--but we also might not be able to, if the mechanism isn't known, or for whatever other reason.
One well known example is that trans women's risk of breast cancer is more comparable to cis women than cis men. If I recall correctly, this is because the relevant factors are basically whether a person has breasts or not, and of course, trans women grow breasts when on estrogen.
The constellation of microbes in the gut did not return to their original, pre-antibiotic compositions in either sex during the duration of the study
This makes me wonder why we don't take fecal samples before proscribing humans especially rigorous antibiotics so they can be used to repair the microbiome afterward.
It was published in 2016 (so may have been superceded by newer studies) but from The Gene: An Intimate History I read that all successful fecal implants to treat Clostridioides difficile required updates every six months to a year from healthy gut biomes - we have not yet figured out how to make a new biome thrive independently, and separately, all probiotic foods have a temporary effect on biomes, they have to be eaten regularly.
Honestly, for PCR, this is a larger N than I would guess is needed. In general, rats kept in constant conditions don't have a ton of variation, even in fairly high-sensitivity assays. I would expect a lot more samples if you were sampling wild rats from the subway system.
I recently looked at a disease course over time for several hundred genes. I only used 6 animals per time point, and both the disease mice and non-disease mice have very little inter-mouse variation at each time point for the vast majority of the genes.
I don't work with antibiotics or directly with the microbiome, but I have some questions about how these rats were housed. As background, I work in autoimmune pharma discovery, and my role is primarily with rodent models of disease. I also sit on my institution's IACUC, so I see a lot of other departments' protocols.
One thing that has become common in some facilities is housing males and females in separate rooms. Female mice and rats get pretty stressed when you house them next to males, or when you handle males first and then females after. This is a damned-if-you-do-damned-if-you-don't situation, because either these rats were housed in different rooms, which could cause microbiome differences, or they were housed together, which could cause stress, which could cause microbiome differences.
I think overall, this study is reasonable, and the fact that it confirms previous studies bolsters the hypothesis, but I'm not sure how you actually tease these out without a mechanistic proposition.
Lastly, based on my experience, there's something a little odd about their weight data. We use weight as a loose proxy for wellness, so it's regularly measured. The body weight for both the males and females are about 30g higher than I'd expect for this age (8 woa). Most rats and mice are very consistent weight for a given age, and this is just a minor red flag, but it makes me wonder more about their husbandry.
Well based on their materials and methods, the antibiotics were all ordered from Sigma, which is not a pharma company, and I doubt they stand to gain much from the study.
What kind of manufacture do you think benefits from this outcome?
Rats are not humans and observed effects in rats and other animals can only occasionally be replicated in humans. The main thing that this does is make it possible to justify further studies, eventually in humans, at which point the issue can be investigated in more depth.
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[ 2.6 ms ] story [ 128 ms ] threadI'm guessing (well, hoping) that everyone agrees that the male/female distinction is medically relevant. E.g., I'd get more from a visit to a urologist than to a gynecologist.
I think there's less agreement about the "di" part of "dimorphism". Obviously most humans fall pretty squarely into the "male" vs. "female" categories, but there's less agreement about there being precisely two, clearly delineated categories.
Some examples:
- hermaphrodites
- conjoined twins with different genders (insanely rare, IIUC)
- non-heterosexuals and transgender people, to the extent that those characteristics indicate underlying physiological differences
> non-heterosexuals and transgender
The discussion here is about biological sex and its medical implications. People who change their gender, or exhibit traits of the opposite gender, aren’t relevant to this conversation.
Edit: commenters below me make some good points that I didn’t consider when writing this. I slightly regret this comment now, but can’t delete it at this point. e.g: the fact that transgender people are relevant to this debate because of HRT, which is true, I didn’t think of that.
This seems obviously false. If the link is based around sex hormones, as an example, then being on HRT clearly changes your risk.
As with all things, correlation vs causation.
Well, they can be – treatment with e.g. hormone therapy has obvious physiological impacts with subsequent influence on the effect of other medical treatments.
Nobody serious doubts that there exist sex-linked physiological characteristics; in reality, the original statement that "sexual dimorphism is real" isn't intended to share knowledge, but a subtle signal about something else.
“Biological sex” is a catchall label for a wide basket of traits that tends to cluster in two large groups. Almost anything attributed to it is, on further examination, really a result of some more specific subset of those traits, which may overlap those certain individuals exhibit that are not stereotypical for their birth gender for whatever reason. So, yes, those differences matter.
Could you explain what you mean here?
When deciding what pronoun to use, biological sex clearly doesn't matter, when talking to a doctor, it may well matter. We can use the appropriate thing at the appropriate time, just as we do with, say, an adopted child, where most of the time you don't need to distinguish, but when it comes to inheritable disease it clearly matters. Likewise, saying "that female over there" when talking about a trans man is utterly useless to me because it doesn't help me identify them without pre-existing knowledge. Man/woman referring to gender identity clearly makes sense for casual conversation, someone's biological sex is none of your business in most cases.
Of course, our increased understanding also says that dimorphism is an oversimplification: the reality is that sexual traits are varied and it is much more of a spectrum, and better understanding of this medically should lead to more personalised medicine that is more effective.
This is especially true when it comes to trans people, if the issue is, for example, linked to oestrogen, then HRT can be more relevant than the chromosomes someone has.
> If we muddy these words to mean gender, then no one will understand what anyone is saying when talking about health, or sexual orientation, etc.
We have trans/cis, male/female, and "biological sex"/"gender identity" to distinguish. We manage to be just fine referring to both biological and adoptive parents as just "parents" and we can still specify where necessary.
> If we are talking about a transman, then you can talk about their sex by referring to them as a woman and as a female. Their gender identity is "transman". Even if they appear to look like a man, their sex has not changed.
Transman isn't a word, it's incorrect. Trans men are men who are trans, in contrast to cis men. Turning it into a single word would be like calling someone a tallman.
No one ever claimed their sex changed, their gender identity is distinct from their sex, that was very much the point.
seems to me that those who insist that gender and sex are distinct also heavily imply that biological sex is mostly meaningless, so its unclear what they actually expect anyone to care about
Gender (either socially ascribed or gender identity, though those two can differ from each other) and biological sex are objectively different things.
Most people who value gender identity rather than the particular indicia of biological sex other people prefer as a basis of socially ascribed gender generally view biological sex as a multidimensional space which includes (among other things, some of which are mutable) gender identity, not a simple binary (even if the distribution may be strongly bimodal.)
> its unclear what they actually expect anyone to care about
Generally, gender identity rather than other factors to the extent that society divides people up by ascribed genders. But also generally a lot less gender segregation, and especially strict binary gender segregation, at all, and when distinctions need to be made to which particular sex- and/or gender-stereotyped traits are relevant, to make distinctions on the particular relevant trait rather than by stereotypical association.
This is a puzzling statement to me. The whole concept of being trans requires that there is a distinction between gender identity and biological sex. If the latter didn't matter at all, being trans wouldn't exist. If anything, trans people would surely be the most aware of biological sex and it's impact on them, as they are not happy with it?
To me, it's like saying an adoptive parent is trying to imply biological parenthood is meaningless. Surely those who wished to have biological children but could not and adopt instead are often the people most sharply aware of it?
Microbes in your gut generally aren't checking sex chromosomes. They interact with sex hormones (see Rizzetto et al., 2018 cited in the paper for this very thing) which often reflect sex chromosomes. Hormone levels or response may not match what is typical of sex chromosomes for a number of reasons including: 46XY women (androgen insensitivity), trans people on HRT, women post-menopause, and sometimes cancer treatment.
IMO it would be less alienating and lead to better health outcomes for everyone if we talked more about testosterone-dominant or estrogen-dominant endocrine systems (or other systems as appropriate).
Also whether dimorphic effects are a result of a one-shot process (e.g. grow testes or ovaries, grow breasts), or a recurring process (hormone levels triggering lactation, sweat patterns).
Basically, transgender brain has some sex-differences that resembles the gender that the person identifies as, and that is before hormone therapies has been applied. If they did such study on antibiotics then you would likely have to do multiple ones, including if the person have taken hormones before or after puberty.
Personally, I much prefer to learn about sex dimorphism in analytical/academic contexts, rather than in emotional/social ones. I actively seek out and read papers like this in my free time.
Largely, this is a problem with society for telling them they are lesser for that, and people having treated them badly because of that, which they have then internalised as shame or a feeling of being less than.
In the adoption example, I would argue that it is not a product of society, but just very present in society. I don't have data to back this up, but kids seem to be innately cruel about things like a peer being adopted, and I don't think it was programmed into them from society.
We are pretty advanced, we can do more than throw our hands up in the air and say "that's how it is" when faced with problems. If we choose not to, it is exactly that: a choice.
In contrast, trans people are usually extremely aware of their biology and related medical requirements - to a greater extent than many others. Like any other topic that might be sensitive, the best approach is to be respectful, accurate, and specific. For example, don't do the thing up-thread of banging on about how "gender isn't relevant to this conversation" without really having that insight.
So, research into the impact of biological sex on medication, and similar, doesn't really seem alienating to me. Despite the existence of trans people, there are obviously two main categories that people fall into in a medical sense.
That said, I do think it would be a mistake to assume that the conclusions of any research into biological sex can be directly extrapolated to trans people. If we know that the relevant mechanism is hormones or chromosomes we may be able to predict effects on trans people--but we also might not be able to, if the mechanism isn't known, or for whatever other reason.
One well known example is that trans women's risk of breast cancer is more comparable to cis women than cis men. If I recall correctly, this is because the relevant factors are basically whether a person has breasts or not, and of course, trans women grow breasts when on estrogen.
This makes me wonder why we don't take fecal samples before proscribing humans especially rigorous antibiotics so they can be used to repair the microbiome afterward.
We know gut flora plays an important role in our health and development.
The C.Diff study with fecal matter transplants was an eye opener, and we are definitely overlooking important data.
interesting study
That being said eat your Natto people :-)
Small N but as a layman it could be potentially significant. Perhaps hormonal changes could be monitored in fecal microbiomes.
I recently looked at a disease course over time for several hundred genes. I only used 6 animals per time point, and both the disease mice and non-disease mice have very little inter-mouse variation at each time point for the vast majority of the genes.
One thing that has become common in some facilities is housing males and females in separate rooms. Female mice and rats get pretty stressed when you house them next to males, or when you handle males first and then females after. This is a damned-if-you-do-damned-if-you-don't situation, because either these rats were housed in different rooms, which could cause microbiome differences, or they were housed together, which could cause stress, which could cause microbiome differences.
I think overall, this study is reasonable, and the fact that it confirms previous studies bolsters the hypothesis, but I'm not sure how you actually tease these out without a mechanistic proposition.
Lastly, based on my experience, there's something a little odd about their weight data. We use weight as a loose proxy for wellness, so it's regularly measured. The body weight for both the males and females are about 30g higher than I'd expect for this age (8 woa). Most rats and mice are very consistent weight for a given age, and this is just a minor red flag, but it makes me wonder more about their husbandry.
Just my 2 cents.
What kind of manufacture do you think benefits from this outcome?