My wife violates many female stereotypes esp. RP ones. Could play chess at 5, interested in science, likes manual labor like assembling furniture, has a licence for operating a forklift and does it well, has little interest in fluffy pretty stuff, is non-hamstering and very rational.

Yet, she has a much stronger childcare instinct than me and dislikes bossing people around so she rejects promotions. And yes, this must be biological IMHO, because it is clear that she was raised in a general absence of feminine stereotypes and expectations (she was raised rural, you know the rural tough gal stereotype who can lay bricks and dig potatoes because the family cannot afford a princess?), or else the above would not be true.

The same way as I am a bit of a softer and more philosophical man, not very good with tools, generally not pragmatic and not really a sportsman, the day I understood there is something biological deep in me, deeper than my generally soft, sheltered, classy upbringing, was when our newborn baby was wailing real loud and guess what my reaction was? Not to try to figure out if it is the tummy hurting or the diaper full. Instead my hands went into fists, my adrenaline through the roof, and I started looking for the thing that is hurting my baby to fight it to death. It took me a few seconds to realize there are actually no wolves in the birth clinic. It was really a deeply buried biological program kicking in.

But I still cannot operate a power drill and spectator sports and car shows bore me to death.

So my position is 80% nurture (or "social expectation" or "parenting") and 20% nature.