Sexy Swallows

Male New Jersey barn swallows with darker breast feathers are more sexually attractive to females of the same species. It's a sad but true fact illustrated in the popular saying "Once you go brown, you never fly around (because you're too busy having bird sex)." You know that saying. Anyway, scientists from Arizona State University wanted to know if sexual attractiveness could increase a male animal's testosterone levels. So they grabbed a few ugly, light-feathered barn swallows and scribbled on them with a black marker. The result? The newly darkened birds became sexual Adonises, and their testosterone production went up within a week. Might this explain why so many good looking guys are complete douchebags? Or as a permanently scarred triple amputee, am I just biased against them? More details here.