Comment by manfredo

> That's a bit of circular reasoning though.

> - Look how men and women behave differently!

> - But why do they behave differently?

> - Because they're different.

> - How do you know that?

> - Because differences are observed at birth, are relatively consistent across countries with vastly different cultures, and the differences in behavior are observed even when raising children in a controlled environment free of gendered roles.

Fixed that for you.