The State of the Scientific “Debate”
Q: Is there a genuine controversy among biologists about the definition of sex?
A: If you’re looking at people studying the evolution of biological sex and sexual reproduction, there is overwhelming consensus. However, they’re insulated from cultural debates—just nerds studying computer models of how selection favored two different gamete types. It’s one of the most robust areas in evolutionary biology.
There are parallels to creationism. If you ask creationists about evolution, they’ll say it’s ‘hotly debated’ because they want to portray it that way. With sex, activist and online discourse began framing the issue as controversial. The controversy was spoken into existence, even though it’s baseless and incoherent.
No empirical findings have overturned the core biological framework. No Nobel Prizes have been given for discovering the supposed sex spectrum. Again, it was just spoken into existence.
What Would Change Your Mind?
Q: What evidence would you need to change your view that there are only two sexes?
A: That’s a crucial question. In the skeptic community, you always need to have something that could convince you you’re wrong. If you don’t, you’re just a zealot, not doing science.
For me, it’s really easy: we define sexes by the type of gamete an individual is biologically capable of producing. You’d need to present a third novel gamete type—in addition to or intermediate between sperm and ova—that an individual’s reproductive system could have the function to produce. That’s the only thing that could make there be more than two sexes.
Why There Are Exactly Two Sexes
Response to Wright’s (2025) “Why There Are Exactly Two Sexes”
Response to Mahr’s (2026) Response to Wright’s (2025) “Why There Are Exactly Two Sexes”
we define sexes by the type of gamete an individual is biologically capable of producing.
As a layman, this is unconvincing to me. I know people who are incapable of producing any gametes. Is their sex simply undefined?
They’ll still have structures in their body that are necessary for producing gametes of one type, and not used for producing gametes of the other type.
“Biologically capable” isn’t specific to an individual here. You’ll see variations on this term such as “biological function”, “organized around”, or “reproductive strategy”. We know that testes are incapable of producing ova. They’re biologically capable of producing sperm. One person’s testes may not, but they’re still male because testes are “for” producing sperm. “For” being a term that isn’t prescriptive. It means the above, about structures necessary for one gamete type and not the other.
An example being worker bees that don’t participate in reproduction. They are still sexed, because they have structures in their body that are particular to one reproductive strategy.
Are people actually
arguingdebating that there‘s two sexes? I thought the point was, that people exist who can’t be assigned to one of the sexes because their body has parts of both. So if I’m not mistaken, there are (in humans) two sexes, but some humans are not clearly one or the other. Which doesn’t mean a third sex, but also doesn’t mean „every human is exactly one or the other.“Unfortunately there’s a lot of misinformation floating around Lemmy. People claiming that gametes are a spectrum and other bad takes.
It’s a matter of academic debate if someone could exist whose sex could not be determined, even by experts. Even in the most extreme cases observed there’s still an identifiable sex.
https://theparadoxinstitute.org/videos/biology-of-dsds-otdsd
Those with this condition do not have both sets of functioning reproductive anatomy, nor both sets of external genitalia, and therefore, cannot fulfill both reproductive roles.
Thus, affected patients develop one reproductive role, and are therefore male or female.
Sex development in humans and other mammals is mutually antagonistic: if one reproductive system starts to develop, it inhibits the other. This is why individuals with Ovotesticular Disorder still develop towards one or the other reproductive role—the genetic and hormonal mechanisms do not allow both male and female systems to fully develop in the same individual. Thus, the inability for the complete development of both systems means that individuals with OT-DSD will have one main reproductive system and one secondary system with partial non-functioning elements.
If you do have parts of both, it’s not a “new sex” but an extremely rare condition (intersex, Klinefelter’s syndrome and others) that will almost certainly come with handicaps (infertility, hormonal imbalance, gynaecomastia…). People with Down’s aren’t “new brained/chromosomed” either, right?
They use “gender” to avoid these uhh controversies. Personally, I avoid the word unless absolutely necessary.
