Charles Darwin’s second book, following upon On the Origin of Species by Means of Natural Selection, has received far less attention than its elder sibling. The Descent of Man, and Selection in Relation to Sex was, in large part, Darwin’s attempt to address a problem that had gnawed at him ever since the publication of Origin. He wrote, “The sight of a feather in a peacock’s tail, whenever I gaze at it, makes me sick!” The feather is unquestionably beautiful, but its evolution is nearly impossible to explain in terms of fitness and natural selection. Why is nature so filled with apparently useless beauty?
Consider the bowerbird of Australia. The adult male builds a bower (which is an elaborate structure that’s not a nest and has no other use) to attract a female… Why do these birds go to so much trouble? Meticulous research has shown that artistic effort on the part of the male, and selective aesthetic preference on the part of the female, have coevolved in a self-reinforcing feedback process. In the male bowerbird, and many other creatures, the power to attract a mate has become inextricably tied to the activity of producing expressions of beauty that have no other practical value and are not signs of overall fitness. Beauty has become an end in itself.
