Thread by @FondOfBeetles

@yorkshirealexx @bloke255 @janeclarejones My definition of sex is founded in developmental and evolutionary biology, where evolution of different gametes has driven evolution of the species-specific molecular mechanisms, reproductive anatomies, dimorphic bodies and sexed behaviour we observe in most higher organisms.

@yorkshirealexx @bloke255 @janeclarejones Thus, my framing is that exhibiting specific molecular mechanisms and anatomy is a *reflection* (biologists would use the word "marker") of your (gametic) sex. These reflected characteristics are usually pretty reliable markers, but not foolproof.

@yorkshirealexx @bloke255 @janeclarejones But that the sum of these markers exist in the first place is because two differently-sized gametes evolved back in your evolutionary timeline.

@yorkshirealexx @bloke255 @janeclarejones That different organisms have evolved different molecular mechanisms/reproductive anatomies/sexed bodies/etc tells us that these markers cannot be considered essential to the phenomenon of sexual reproduction via differently-sized gametes.

@yorkshirealexx @bloke255 @janeclarejones That is to say: a male asparagus plant does not have a penis, so a penis cannot be considered an essential part of the process of sexual reproduction (which is why we have sexes in the first place).

@yorkshirealexx @bloke255 @janeclarejones And so on for pretty much every marker of sex.

So that's why, from this biologist, the single characteristic that links every organism that reproduces sexually via differently-sized gametes is the *only* characteristic that can be deemed "sex".

@yorkshirealexx @bloke255 @janeclarejones But back to the markers (it *is* going somewhere, promise).

So, in a healthy person, gametic sex is associated with a specific gonad type, which causes development of specific reproductive anatomies and so on.

@yorkshirealexx @bloke255 @janeclarejones Sex is framed by some as a "cluster concept". @janeclarejones might explain it better than me, but this approach uses the set of reproductive markers to define sex. None of these markers is, as I understand, weighted more heavily than another.

@yorkshirealexx @bloke255 @janeclarejones And possession of "some" ("most?") of these markers is sufficient to include you within the category encompassing those markers.

I do not agree with this cluster concept of sex but, in my academic world, disagreement is allowed :)

@yorkshirealexx @bloke255 @janeclarejones It would be true to say that, outside of developmental biology or philosophy, "real world" people rely almost entirely on one marker as a definition of sex - that is, penis+testicles = male, and vulva = female.

For the majority of people, that is accurate. The markers are good.

@yorkshirealexx @bloke255 @janeclarejones i.e. most people with penises+testicles are (if healthy) gametically male and most people with vulvas are (if healthy) gametically female.

So the language of the debate changes depending on who you are talking to. We are all fundamentally asserting the same premise though :)