>>that's not what " sex is a spectrum" means. It doesn't mean there is no dimorphic sex, that would be an absurd point of view. It means that there are genetic differences in sexual characteristics of members of the same sex.>>
I hate to say it, but there are people who hold that absurd point of view. They think not only that there are (phenotypic) differences between members of the same sex, but that some people can somehow be, say, 70% male and 30% female *in terms of their sex*. Further questioning usually elucidates that their definition of "sex" isn't about gamete, but things like hormone levels and secondary sex characteristics. But not always; "intersex" (more accurately: people with DSDs) is often used to demonstrate that people can be "both" sexes. There's usually then a flurry of searching through PubMed on the search terms "human + hermaphrodite", which reliably turns up some papers from the 1970s-1990, before ovitesticular syndrome was renamed.
>>everything is continuous.The idea of defined categories, especially when it comes to biology and evolution, is a socially constructed myth used to coopt these views with creationism.>>
No; some things are discontinuous, especially in nature. At the atomic level, there are discrete energy bands for electrons; the discontinuity of emissions in the photoelectric effect (https://en.wikipedia.org/wiki/Photoelectric_effect) shows how photonic energy is quantized, not continuous. Nature is thus discontinuous at its most fundamental level.
In biology, we have separate categories of gamete in human. We evolved from asexual single-celled organisms - absolutely! And somewhere along the way, some of those organisms evolved from isogamy to anisogamy, with discrete, different gametes for reproduction. And, if you play the evolution game for long enough, it turns out that one winning strategy is for one gamete to be small, inexpensive and motile, and another to be large, expensive and immotile. In such a strategy, there's no benefit in a third in-between gamete because it loses in any competition with the other two. (Other organisms have evolved other, different strategies. All valid. It's just we humans don't use them. This doesn't make sexual selection "better". It just means it's the one that works for us, and we have to accommodate its demands and realities.)
We don't make our sex. We observe it. Anyway, glad you don't think I'm a creationist. I'm very definitely at the opposite end of the belief spectrum (hah) from that pov.
>>there are an array of secondary sexual characteristics which very between male, female, and intersex people.>>
"Intersex" people (please: people with DSDs, differences of sex development is the usage favoured by doctors and scientists since 2005) are still male or female. But yes, we all display an array--you could even call it a spectrum--of secondary sexual characteristics. This is uncontroversial, but doesn't mean that the owners of those characteristics are anything but male or female.
>>You can literally look at gonads in every stage of development where they turn from ovaries and a clitoris into testicles and s penis.>>
That's not quite right. From https://www.ncbi.nlm.nih.gov/books/NBK222286/ : "During early development the gonads of the fetus remain undifferentiated; that is, all fetal genitalia are the same and are phenotypically female. After approximately 6 to 7 weeks of gestation, however, the expression of a gene on the Y chromosome induces changes that result in the development of the testes."
IOW the embryonic gonads aren't "ovaries and a clitoris"; they are structures which in the absence of SRY will become those, but they aren't (yet) in any meaningful sense "ovaries and a clitoris". That may sound like splitting hairs, but it's important to distinguish between structures which will become something if everything proceeds as usual, and the finished product. There's many a slip between cup and lip, which is where DSDs, figuratively, occur.
