The effeminacy which a majority of homosexual men exhibit to some degree isn't natural. I have known of enough men who rapidly developed effeminate mannerism once they adopted and embraced the 'gay identity' that I believe there is a physiological change that is brought about in the brain through chosen behavior. It's interesting how the brain can be morphed by chosen behavior, which is all the more reason to support reparative therapy for men with unwanted same-sex attraction.
It might be as simple as which side of the brain you employ as a filter for everything you observe and do.
I really don’t know...