Actually, it's really interesting, but there are theories that suggests that gender segregation started happening only as we introduced agriculture and we became sedentary societies. When we were hunters and gatherers, the job was split equally among genders.

That is what my professor said as well. In the agrarian times, whatever they get from the field was spilt equally between men and women. It is only till the industrial revolution did the idea of men being the ones going out and working sink in.