>>10629975 (pb)
Polydactyly also occurs in animals.
Your post reminded me of a polydactyly reference in popular culture. In "The Princess Bride" one of the villains was a "six fingered man".
I haven't paid much attention to Mike Adams and Natural News recently, but back when I did, I remember him discussing the possibility that the earth was being terraformed for alien invaders. (His idea, I believe, about why the wicked people seem to want environmental destruction.) He mentioned at some point the fact that having extra digits would make a species much more able to do certain tasks. Evolutionary benefit to polydactyly, perhaps?
I have wondered about the whole "y" concept. I wondered if it referred to the sex chromosomes as they are "x" and "y". I also have seen posts about the appearance of the external part of the ear. This theory (reference to polydactyly) makes some sense, too.