The conventional view in academia today is that sex is biological, but gender is a cultural construction. That is, roles that are attached to being male or female are nothing more than the impositions of culture. Well, I just observed my 15-month-old granddaughter picking up her first doll. She had played with teddy bears and the like, but she never even saw a doll that looked like a baby. This one wasn’t hers. But she picked it up, cradled it, supported its head, and kissed it. How did she know to do this? No one taught her to. She is not particularly receptive to culture at her age. Her brother, at the ripe age of three, had no interest in that particular toy, even though he has some inchoate notions of babies from the existence of little sister. But she knew immediately how to play mommy.