EDIT: Ignore the rest of this... just see WrongBot's comment. (Hm, there's no way to do strikethrough in Markdown, is there?)

To recall something related that came up here recently and might be worth mentioning, I seem to recall someone (Alicorn, I think?) posting something here recently about a culture that actually hadn't figured out the sex/pregnancy connection, due to their diet containing many natural contraceptives (being largely based on yams, IIRC?)? And that still doesn't really acknowledge it culturally now that they've learned about it? Though those were not foragers, IIRC.

I can't seem to find it right now, though... can anyone remember what I'm thinking of?