Gender or Sex: Which Causes the Divide?

In reading Revisting Shakespeare and Gender, I took note of an immediate error. The reading describes Shakespeare's prowess in analysis and blending of gender norms to reveal "what it means to be female", however "female" is the incorrect word. The words "female" and "male" are specifically about biological sex. "Woman" and "man" are words meant to distinguish gender (you may be a woman without having the biological parts of a female..etc). I believe this distinction is incredibly important because it helps to clarify my opinion on the following question: 

Gender or Sex: Which Causes the Divide?

In class, Mrs. Hamovit discussed the roles of women and men. I know that in Ancient Greece and the Italian Renaissance, the ideal woman was full figured with ample breasts, a rounded stomach and fair skin. This immediately reveals something to me...a ideal cisgender female was fertile (as Hammy mentioned), but also worked very little (lack of a tan). Who knows why the latter point became important aside from more easily revealing the flush of a woman's cheeks...but I digress. Either way, I believe most of the divide between roles had more to do with sex than gender. 

Gender is a social construct. Sex (whether binary or not) is very distinct biologically. Males inseminate females, females bear children. Whether or not we like the ring of the word "female" on our tongue, it is a distinct part of our identity. I believe there is a very concrete divide between sexes, but a line far more blurry between the infinite genders that exist. 

I could go on more about gender expression and expand on Shakespeare's use of androgyny, but I don't think it's that relevant right now...maybe more for class. Either way, quite intriguing for our first go at Women's Studies!