Evo Psych Bingo!
As LabRat says, there is legitimately such a thing as evolutionary psychology, but going around saying we should have 1950s gender roles and/or promiscuous polygyny, because science and because cavemen is not how it really works.
(I always wonder if "1950s gender roles" even really existed in the 1950s. They do show up in the media of the time, but when I talk to people who were alive then they always paint a much more nuanced picture, with a lot of working mothers and non-nuclear families and non-useless fathers. I suspect that the "housewife, breadwinner, Junior, and Sis" family model was somewhat more prevalent in the 1950s, but hardly universal.)