I had a thought recently that has given me a little lift of my spirits when I'm feeling down or strange about not having any hair on my body. I've been a student of evolution for many years, and have enjoyed reading books (by, for your reference, authors including Stephen J. Gould, Richard Dawkins, David Quammen, Niles Eldridge, and others....) I've been particularly interested in human, or "hominid" evolution. Here's what I think:
Alopecians are not "defective" or deficient in any sense. On the contrary, we're actually in the vanguard of human evolution...the next step! Our species has been called "The Naked Ape" (a book by Desmond Morris). If you look at other primates on our particular evolutionary tree branch, the trend in hominid evolution is clearly toward LESS hair - humans have a lot less hair than our nearest relatives, the chimpanzees (who share something like 98% of our DNA).
I think that in the future, Homo sapiens will be totally hairless. Evolution is about adaptation to environment. As traits become more useful in terms of survival and reproduction, those traits are passed on. As traits become less useful, they are modified or discarded entirely. For example, the land-dwelling distant ancestors of whales used to have legs and hoofs and hair.
Humans no longer need hair covering their bodies. It serves no evolutionary advantage in a world where we no longer need fur for warmth. (And, since so many women and men wax and shave in order to be MORE attractive to sexual partners, being hairy probably doesn't convey a reproductive advantage anymore.)
So, this is my theory and I'm sticking with it. I am a highly evolved being...an example of the future of humankind!