Too many posts to catch up,,,,!!!
First it's likely worth reading this article by Jenny Graves, who is a Distinguished Professor of Genetics at Victoria's La Trove University, and also the 2017 recipient of the Prime Ministers Prize for Sciene.
The article was titled: "What makes you a man or a woman? Geneticist Jenny Graves explains.
Link: https://theconversation.com/what-makes-you-a-man-or-a-woman-geneticist-jenny-graves-explains-102983
The Conversation is a semi-academic web journal, that discusses serious issues, especially for those who want to live an evidence based life.
There's also another article by Graves, in another issue of The Conversation.
This article explains how key genes active early in life transform the embryo into a woman or a man, and that genes active later control how sex is expressed in physiology and behaviour.
Quote: "But in embryos destined to be boys, the genital ridge receives a signal called the “testis determining factor” at ten weeks after conception. This signal kick-starts development of testes and suppresses ovarian development.
If it doesn’t get the testis signal, the genital ridge waits a few more weeks, and becomes an ovary."
Link: https://theconversation.com/how-genes-and-evolution-shape-gender-and-transgender-identity-108911
Before that process, all embryos are more or less the same from a biological gender perspective. (But may still have different outcomes, a process that is highly dependent on the potential influence of that embryo's genes.
Once we fully understand this process we can more easily appreciate the wide variety of possibilities in what constitutes both maleness and femaleness. If we do not understand that process, then we may hold some of the "strong" (but incorrect) opinions we find expressed on this topic.