An earlier post on all you need to know about hair proposed that the evolutionary function of male baldness is to honestly signal his future commitment to his would-be first wife, rather than continue playing the field into middle and old age. I'm not talking about the receding hairline around the temples, but a steady march backwards, usually leaving just the lowest part of the back and sides with hair.
Via Ray Sawhill / Michael Blowhard, here's a look at 53 rock stars then and now to get a feel for what males look like who stay on the mating market for most of their lives. Some guys are wearing hats, but that doesn't mean they're covering up baldness -- Bob Dylan and Bret Michaels aren't balding, for example. Of the 40 males, I see 4 that are sort-of / sort-of-not -- Bruce Springsteen, Meat Loaf, David Lee Roth, and Iggy Pop. Only 4 look truly balding -- Tom Petty, Sting, David Crosby, and Neil Young.
Most of these guys are in their 50s or 60s, a good reminder that baldness is not an effect of aging. As I said in the hair post, loss of pigmentation is what signals age, whereas balding signals how monogamous your mating strategy will be in the future. Only 1/10 of rock musicians have male pattern baldness, and even they don't go against my overall point that those who stay on the mating market for a long time keep most of their hair. Those 4 are the not-so-womanizing ones out of the bunch, while the ones who've slept with thousands of groupies over their lives aren't balding.