2012.06.22
Bruce Willis isn't worried about losing his hair. In fact, he says fuck it, and goes on to shave it all off completely. But unlike THE MAN, there are lots of men worried about losing their hair. Instead of fretting about beauty, it make s sense for them to count their blessings because by right, bald men should be extinct by now.
New Scientist has taken at look a that particularly interesting question in a wonderful feature, and looks to get to the bottom of why baldness should still be so widespread amongst males.
The hair on our heads may protect us from the noonday sun, maintain body heat when it is cold, and even attract a mate. If so, men who lose their hair are at a disadvantage, and you would expect natural and sexual selection to have weeded them out. So why haven't bald men like me, or at least our versions of genes, gone extinct?
One early stab at answering this question rested on the idea that a man's genetic predisposition to baldness is found in genes he inherited from his mother. Since she would not have suffered baldness and its concomitant ill effects, natural selection would have no cause to remove these genetic variants. But think about it carefully and the logic fails - mothers are just as likely to have sons as daughters and every time they do, if these males are less likely to procreate, these variants should become rarer. In any case, science has shown that this mother-based hypothesis is wrong.
Scientists have recently been positing that baldness offers some kind of evolutionary advantage. Some researchers suggests that it signals dominance and status, while others suggests that it shows people they offer maturity, wisdom and nurturance.One early stab at answering this question rested on the idea that a man's genetic predisposition to baldness is found in genes he inherited from his mother. Since she would not have suffered baldness and its concomitant ill effects, natural selection would have no cause to remove these genetic variants. But think about it carefully and the logic fails - mothers are just as likely to have sons as daughters and every time they do, if these males are less likely to procreate, these variants should become rarer. In any case, science has shown that this mother-based hypothesis is wrong.
According to one recent study, baldness allows more sun to penetrate through skulls of aging men which in turn is diminishing the odds of developing prostate cancer. That's interesting, sure, but also completely unproven.
For now, nobody knows for certain why bald men still exist, but check out New Scientist's article after the jump. It's a fantastic read. [New Scientist]
