What is the main thesis of the work?

In her 1949 book Male and Female: A Study of the Sexes in a Changing World, anthropologist Dr. Margaret Mead studies the gendered expectations and behaviors of seven societies in the South Pacific, including the Samoans, the Tchambuli, and others. She examines the biological and social realities of these societies with regard to gender in order to compare them to the biological and social realities of gender in contemporary Western society. In doing so, Mead was attempting, in a time in which gender roles and gendered expectations were starting to come under new scrutiny, to get her Western readers to rethink their conceptions of gender.
Her main thesis is the claim that in studying these South Pacific cultures and comparing and contrasting our own (Western, American) culture, "...we can get some sense of the process of learning to be male, learning to be female, some recognition of how we ourselves arrived at our own sense of our own sex" (5). In doing so, Mead believes "...we, as a civilization, may make as full a use of women's special gifts as we have of men's, and in doing so develop forms of civilization that can make fuller use of all human gifts" (6). Examining the gendered expectations of other cultures allows us to understand the ways in which gender and sex might be created by society and the ways in which they might be biological realities, and this will then help us to understand ways we can structure our society to be fair and efficient.
https://books.google.com/books/about/Male_and_Female.html?id=L6nWFwcJNZ4C&printsec=frontcover&source=kp_read_button