[Trep]

I think you need to study more and eventually get a PhD. I think it's a little of both. Each sex is born with a biological predisposition to go with one role or the other. BUT, it can be steered (i.e. manipulated) by social conditioning - pink for girls, blue for for boys; Barbie for girls, G.I. Joe for boys; Home Economics class for girls, and sports for boys. Conversely, studies have shown that roles can be 'switched' for each gender also by social conditioning. There are as well other various factors - culture, religion, socio-economics, technological and industrial, etc.

And there are variances in how this works. There are some primitive tribes where the women dominate the men in some ways. There's also research done showing that male sons of Lesbian parents tend to be more nurturing and less aggressive than boys raised by 'traditional' heterosexual parents. And how are effeminate men explained? And aggressive women who play sports to compete? There are also instances of males wanting to become female through sex change operation, and vice versa.

Keep in mind, too, that most of the world no longer lives in a primitive 'hunter gatherer' phase, hasn't for centuries, and that humans are still evolving and becoming even more complex, thus the cultures and societies we live in are also evolving, often to the point where gender roles have finally become a matter of choice.

It looks to be far more complicated than your 'mental imprint' suggests. There are many other influencing factors involved, especially today, with gender roles themselves becoming more of a choice based on a bunch of factors.