Dr. Martin Hash Podcast

Males and females each start out with a single set of chromosomes that double then doubles the doubles continuously until there's you. Of that first set of chromosomes, 22 of the 23 are exactly the same between males and females, however, the 19^th chromosome is shorter in males, called the Y chromosome, versus a female's longer 19^th chromosome, called X. Females have biological machinery in that missing area that turns off testosterone, meaning males have testosterone turned on by default. Testosterone then initiates the cascade of changes that make the body into males, and keeps the body acting male throughout life.

In a very real sense, testosterone is the fundamental difference between men and women. In fact, females who inject themselves with testosterone will take on the attributes of men, and males who have their testosterone nullified in some way appear effeminate. This can also happen if there is a birth defect, and has led to some bizarre situations; for example, testosterone-resistance means a genetic male can’t be physically distinguished from a female even into maturity; sometimes not knowing until that individual wants to find out why they aren't getting pregnant. Conversely, there are also genetic women with penises similar to men. Many in the transgender community cite these extremely rare cases as proof that they are actually the opposite gender because they think they are, but the fact is, Y-chromosome females have a biological anomaly that prevents their testosterone from working, and X-chromosome males have a physical aberration that produces high levels of testosterone. These aren't just examples of someone thinking they are the other gender, their body's literally operate as if they were.