If you want to become an expert in human biology, I’m not the guy you need to talk to, but an oversimplified explanation of what determines the gender of a baby is the presence or absence of a Y chromosome in that tiny human. If the Y is present, paint the nursery blue. If there is no Y, buy pink blankets.
Because it is this “small” difference that separates the boys from the girls, some folks think that there is very little difference between the males and females of the human race. We are told that society and culture, with our stereotypes and traditional expectations, force girls to like baby dolls and frilly clothes. Remove those, some say, and the differences between boys and girls will go away.
I’ve already told you I’m no expert on these matters, but I’ve lived long enough to know that the difference between male and female runs a whole lot deeper than that. While both sexes experience life through our emotions, we project and deal with them differently. While our desires and ambitions run along the same course (we both want companionship, desire success, that sort of thing), we think and go about it differently.