Given that cultural norms in countries where men are expected to have separate tubes for each leg in their lower garments (ie. trousers) are virtually never strayed from, it follows that there will of course be other similarly strong cultural norms that men or women follow
Scotland proves that there's nothing unique about a male brain that means they can only wear trousers, it's purely socially imposed, yet has such a strong effect - why wouldn't tendency to violence be similarly culturally created
The natural world over, it is males who tend to be the aggressors; the ones fighting for territory, to establish alpha male, or for access to females. Female aggression exists, of course, often in defence of the nest of the young; and females sometimes also kill their own young.
There are obvious biological differences between the sexes, which can most often be seen at the extremes of behaviour or aptitude.
Physically too, obviously, the bodies were 'designed/evolved' for different functions. Females tend to have nimbler fingers; males have far greater upper body strength.......and so on.
Most women who have given birth know all about the flood of hormones that create an almost physical bond between mother and child; and most men are far more visual when it comes to sexual stimulation.....
It is not all cultural.