For the lurkers, let’s review the accuracy of these statements.
WHAT IS SEX?
Sexual reproduction is the creation of a new member of a species by the fusion of two different gametes - a small gamete and a large one. This is the case throughout the animal world and evolved 1.4 billion years ago.
yes.
The sex of an individual = whether your body is designed around the production of large gametes or designed around the production of small gametes.
sex is not always assigned on the basis of this. Sex is usually assigned on the basis of the external appearance of the genitals, which usually, but not always, corresponds to gametes.
There are only, and exactly two, gametes (sperm and egg), therefore only, and exactly two, sexes. Small gamete producers are known as males, large gamete producers as female.*
This is not true no. There are plenty of people whose bodies do not produce gametes at all. Furthermore , there are people “known as” female whose bodies do not produce large gametes
The words "sex", "female" or "male" might change, but the biological process of sex and the categories of male and female are immutable.
what do you mean by the “biological process of sex and the categories of sex are immutable”? This is an ideological statement.
We did not create the categories of male and female, we merely named them.
yes and no. We observed the world and invented conceptual categories to describe our best observations. As always with science, those observations were complicated by the invention of new scientific technologies, and we learned more about the variability within categories and the ways in which we had infused these conceptual categories with meanings that don’t in fact reflect the diversity of the empirical world.
GTG will finish the rest later. …
*Recognition of sex is instinctive in animals, including in humans. It is very rarely necessary to see genitals or test chromosomes in order to recognise the sex of adults.
DETERMINATION OF SEX AND SEXUAL DEVELOPMENT
Your genitals are excellent evidenceof your sex because they correlate to the gametes your body is supposed to produce. A penis is the delivery system for sperm, for example. But it is not the case that your genitals (or your chromosomes, for that matter) are your sex, or decide what sex you are.
Your penis does not decide your sex - you develop a penis because you are male and sexual development in the womb has proceeded normally.
Your chromosomes do not determine your sex. XY and XX karyotypes have become shorthand for male and female in the same way as penises and vaginas have. But that is evidence of sex, not sex itself. Sex in humans (ie which gametes you are designed to produce) is determined by the SRY gene, which is almost always located on the Y chromosome. It is the determiner of whether the fertilised egg will develop along the male or the female pathway. Hence the XY and XX shorthand.
DSDs
Sexual development in utero is a complex and finely tuned process and very occasionally goes wrong - sometimes very awry. In a subset of those cases, genitals can be ambiguous at birth and so it is not possible to deduce the baby's sex from them. That is when other tests are used to determine the sex of the baby.
All DSDs are sex-specific ie are either the result of disruption or incomplete development of a male in utero or a female in utero. Not both. A female embryo can have a genetic deficiency in the enzyme alpha-reductase and the structures of her internal and external genitals will develop normally. Whereas those of her fraternal male twin, also deficient in the enzyme, will not. Because he needs alpha-reductase to synthesise testosterone into the hormone DHT, which is needed to form a full penis in utero. As a female, a penis is not part of her sexual development.
TAKEAWAYS
- Your sex is a description of which of the only, and exactly, two kinds of gamete your body is designed to produce
- Your sex is decided at conception by the presence or absence of an active SRY gene in the sperm AND
- Your sex cannot be changed - we know of no mechanism which will change a human small gamete producer into a large gamete producer, or vice versa.
Therefore there is no point of anyone's existence - from fertilised egg to baby to mature adult - at which they are neither or both sexes.