The structures that unambiguously always define male or female are the structures that produce functional gametes. I interpreted “how folks that were never going to produce either fit into that definition” as asking “If we don’t look at the gonads, what would we use to determine sex”. Those ducts are a very good indicator, but are secondary structures around the gonads. If you wanted to determine sex without looking at gonads, those are one of the primary structures for doing so.
Ovotestes are interesting, but probably not what you’re thinking. They’re not just normal testes and ovaries as one might be lead to believe from the name. They’re exceedingly rare, so have to be examined individually and general statements can’t really be made. You’ll probably find a (semi-)functional gonad from which their sex would be determined, with a sampling of non-functioning tissue from the other sex. You’ll also likely find that the surrounding structures and rest of their body is unambiguously male or female, though again you’d have to look at a specific case.
To bring it around to near the start of this thread, even then, the body isn’t organized around producing no gametes. It’s organized around producing gametes and failing to do so.
the body isn’t organized around producing no gametes.
After looking some case reports it looks like a lot of folks with ovesterticular disorder have both sets of genetalia and neither can produce gametes. These folks tend to choose a gender (usually the one they grew up as pre-puberty) and get hormone therapy and such to affirm it.
Since “sex is a binary” is a universal claim, it only takes one existential example to disprove it. I was pretty convinced by the case reports I read that the sex binary can’t include every person.
I’d be convinced if ya presented a definition that could be used on everyone.
But at this point I think we are splitting hairs. It seems obvious to me that there is a range of ways sex can exist in humans. At this point a definition for the binary would have to be pretty complex and people close to the boundary would likely be very similar despite getting opposite labels. It’d be like saying there is a binary of black and white and the line is at R127,G127,B127. I mean sure, but we both know we are just drawing a line in a spectrum.
Those are variations within a sex. Chromosomes/genes/etc aren’t how sex is defined. The paper that I link to in my sibling comment (Why There Are Exactly Two Sexes) explains why trying to use that as the definition of sex is incoherent.
Even if I’ve failed to convince you, thanks for actually trying to understand, unlike most in this thread. The best link I can provide for further reading is probably this peer-reviewed article published by a biologist, Why There Are Exactly Two Sexes. Here’s a few quotes:
Across anisogamous species, the existence of two—and only two—sexes has been a settled matter in modern biology
Here I synthesize evolutionary and developmental evidence to demonstrate that sex is binary (i.e., there are only two sexes) in all anisogamous species and that males and females are defined universally by the type of gamete they have the biological function to produce—not by karyotypes, secondary sexual characteristics, or other correlates.
This commentary advances a simple claim with broad consequences: In anisogamous organisms, the sexes—male and female—are functional classes defined by the type of gamete an individual has the biological function to produce (Bogardus, 2025). Males have the biological function to produce sperm; females have the biological function to produce ova (Parker et al., 1972). That definition is universal across all anisogamous taxa
As I’ve said elsewhere in the thread, nothing I’ve said here is actually a claim that I myself am making. I’m simply stating what the consensus is. Trying to find flaws in that definition is how science works, and it’s healthy to poke at it.
That article seems to counter your above points about using secondary characteristics pretty directly.
As well:
However, the existence of such conditions does not undermine the binary nature of sex, because the sex binary does not entail that every individual can be unambiguously categorized as male or female.
The article counters the claim that everyone can be placed into the binary.
It seems that “sex is a binary” but we have to exclude folks that don’t fit into it. Looks like the meme we’re commenting on is still pretty applicable lol.
So now to me it looks like sex is a binary nested in the larger binary of unambiguous and ambiguous sex. Giving folks 3 places they could end up, one of those places (ambiguous sex) being a spectrum. But thats only if we are going to be super technical. I probably wouldn’t correct someone for seeing that disjointed spectrum as a regular spectrum.
I do love a pedant though. I’m not even joking. For example: the comedian David Mitchell.
It’s been fun taking the time to learn all of this. Thanks for all the links.
Although rare, some individuals have disorders of sex development (also referred to as intersex conditions). Most of these disorders are male or female specific and do not cause ambiguous biological sex. Some individuals have reproductive anatomies with both male and female features; here, biological sex classification is a complex process with input from medical professionals and parents. Not one of these individuals represents an additional sex class.
I think the answer you’re looking for is that ambiguous is being used in the sense of “not immediately obvious, requires further investigation”, not “impossible to know in principle”
Either way, thanks for the conversation (and pedantry!)
The structures that unambiguously always define male or female are the structures that produce functional gametes. I interpreted “how folks that were never going to produce either fit into that definition” as asking “If we don’t look at the gonads, what would we use to determine sex”. Those ducts are a very good indicator, but are secondary structures around the gonads. If you wanted to determine sex without looking at gonads, those are one of the primary structures for doing so.
Ovotestes are interesting, but probably not what you’re thinking. They’re not just normal testes and ovaries as one might be lead to believe from the name. They’re exceedingly rare, so have to be examined individually and general statements can’t really be made. You’ll probably find a (semi-)functional gonad from which their sex would be determined, with a sampling of non-functioning tissue from the other sex. You’ll also likely find that the surrounding structures and rest of their body is unambiguously male or female, though again you’d have to look at a specific case.
To bring it around to near the start of this thread, even then, the body isn’t organized around producing no gametes. It’s organized around producing gametes and failing to do so.
After looking some case reports it looks like a lot of folks with ovesterticular disorder have both sets of genetalia and neither can produce gametes. These folks tend to choose a gender (usually the one they grew up as pre-puberty) and get hormone therapy and such to affirm it.
Since “sex is a binary” is a universal claim, it only takes one existential example to disprove it. I was pretty convinced by the case reports I read that the sex binary can’t include every person.
I’d be convinced if ya presented a definition that could be used on everyone.
But at this point I think we are splitting hairs. It seems obvious to me that there is a range of ways sex can exist in humans. At this point a definition for the binary would have to be pretty complex and people close to the boundary would likely be very similar despite getting opposite labels. It’d be like saying there is a binary of black and white and the line is at R127,G127,B127. I mean sure, but we both know we are just drawing a line in a spectrum.
This is from Scientific American in 2017
Those are variations within a sex. Chromosomes/genes/etc aren’t how sex is defined. The paper that I link to in my sibling comment (Why There Are Exactly Two Sexes) explains why trying to use that as the definition of sex is incoherent.
Even if I’ve failed to convince you, thanks for actually trying to understand, unlike most in this thread. The best link I can provide for further reading is probably this peer-reviewed article published by a biologist, Why There Are Exactly Two Sexes. Here’s a few quotes:
As I’ve said elsewhere in the thread, nothing I’ve said here is actually a claim that I myself am making. I’m simply stating what the consensus is. Trying to find flaws in that definition is how science works, and it’s healthy to poke at it.
That article seems to counter your above points about using secondary characteristics pretty directly.
As well:
The article counters the claim that everyone can be placed into the binary.
It seems that “sex is a binary” but we have to exclude folks that don’t fit into it. Looks like the meme we’re commenting on is still pretty applicable lol.
So now to me it looks like sex is a binary nested in the larger binary of unambiguous and ambiguous sex. Giving folks 3 places they could end up, one of those places (ambiguous sex) being a spectrum. But thats only if we are going to be super technical. I probably wouldn’t correct someone for seeing that disjointed spectrum as a regular spectrum.
I do love a pedant though. I’m not even joking. For example: the comedian David Mitchell.
It’s been fun taking the time to learn all of this. Thanks for all the links.
Posted another link elsewhere that explains the ambiguous terminology a bit:
https://projectnettie.wordpress.com/
I think the answer you’re looking for is that ambiguous is being used in the sense of “not immediately obvious, requires further investigation”, not “impossible to know in principle”
Either way, thanks for the conversation (and pedantry!)