One of me and the wife's favorite debates is the differences in the brain between the genders.
There is a LOT of research done on the different brain chemistry/design. Generally speaking the theory goes like this: In the cave man days, men were hunters, we could focus on the task at hand (and not much else) very well. Whereas women being more gatherers and raising children would need to focus on many things at a time, even if not more intently.
Now, this does lead to some interesting noticeable differences in what jobs each gender is better at, and strangely it doesn't align very well with the stereotypical jobs. IE: men would make good high stress leaders (submarine commander, emergency response, and business managers in high stress fields). We would not be good at anything that involves organizational skills or anything that requires attention to detail -- professional driving, auto mechanic, or managing a large number of staff in a non-high stress job.
Women are pretty much the opposite, great at secretarial work (not to be offensive, but it involves multi-tasking and organization), large scale management (100+ employees), and anything involving long term planning.
It is just strange that instead of the gender differences getting used to the best advantage, some stereotypes seem to persist.
As for things like underground mining -- the sad truth is that very few underground miners will actually go down to work while a woman in underground. It is considered bad luck and they fear that everytime a woman goes under, someone will die. It is sad because in a industrial setting, women have VERY FEW accidents as the adherence to safety protocols is near perfect.
I spent some time doing investigations for industrial accidents, women are more safe than men, and by a whole lot. Seems there is a lot less of "I'm tough so I can do it" and "It will never happen to me". The one I do like to see is that men will let their co-workers break safety rule to get the job done, were women will almost always call you out for doing something stupid.
Of course, I married a feminist sociologist, I should have known what I was in for
hint: that means I don't wear the pants in my family.