Best guesses at an explanation for that one:
1) A lot of older men had some homosexual experimentation in their past, decided that they therefore count as bi, but are now only interested in heterosexual relationships.
2) A lot of older men choose to signal what they believe to be the desirable characteristic of “sexual adventurousness” to their actual target sexual partner, which is younger women.
Plus, there may be many bisexual men specifically looking for a partner they can breed with. Based roughly on barely remembered male fertility age statistics, I’d guess men would be most interested in fathering children in the 25-45 age rage, and there does seem to be a bit of a hump in the data in that range.
Best guesses at an explanation for that one: 1) A lot of older men had some homosexual experimentation in their past, decided that they therefore count as bi, but are now only interested in heterosexual relationships. 2) A lot of older men choose to signal what they believe to be the desirable characteristic of “sexual adventurousness” to their actual target sexual partner, which is younger women.
Plus, there may be many bisexual men specifically looking for a partner they can breed with. Based roughly on barely remembered male fertility age statistics, I’d guess men would be most interested in fathering children in the 25-45 age rage, and there does seem to be a bit of a hump in the data in that range.