Quote Originally Posted by Anatha View Post
I have never heard of sex referred to as a spectrum. It's not binary, sure, but it's definitely not a spectrum. It's a biological assignment based on chromosomal markers.
Gender is the one that's a spectrum, since it's entirely couched in personal identity/how one relates themselves to the culture they inhabit.
Matters get real messy when people start conflating and confusing one as the other. So don't.
Nono, we are definitely talking about sex also being seen as a spectrum, just like gender. Whatever genetic markers you go look for in humans, even if your technique would have a 100% accuracy, would still only give you a probability, however good, that that person would have been born with a particular set of genitals, which is where the concept of 3G-sex comes from (genetic-gonadal-genitals). Now, at first glance this seems to be internally consistent for 99% of all humans, so yay, pretty binary and totally not a spectrum.

That is, of course, assuming that having been born with a particular set genitals and all the other bits, bops and G's is the defining feature (and keeping our scientific fields of inquiry laser-focused on genetics and biology) and looking away from the variance within the categories we just created. But the concept of intersex alone, which is pretty narrow in itself, basically an internally inconsistent 3G-sex, is still complex enough to generate definitions which can give a delta of a factor of 100 in prevalence % depending on which ones you run with. And intersex is just one of the many results of our sex determination slipping up. There are many other ways as well without breaking 3G-sex consistency at all which can blur the lines. For example, to address transgenders, no doubt the elephant in the room, one promising avenue of research into the biological causes of dysphoria is estrogen's critical sprinkling of the brain right before or after birth, resulting in the 'masculinization' of the brain, and if this goes wrong you end up with the wrong combination of brain and phenotype. So, yeah, plenty of reasons to doubt a pure and simple dimorphic system is a helpful construct beyond basic and general applications.

Anyway, just saying that even in biology and neighboring fields matters aren't really that clear-cut.