The Explainer blog on Slate tackled this interesting question: “When and how did humankind figure out that sex is what causes babies? It’s not exactly the most obvious correlation: Sex doesn’t always lead to babies, and there’s a long lead time between the act and the consequences—weeks before there are even symptoms, usually.”
The responses cited societies even in the 1900s which didn’t see a relationship between sex and children. Does anyone else find this interesting?