Monday, January 1, 2018

Aesthetic Evolution: Not Convinced

Since I have been a birder for more than forty years and have long had an interest in natural history, my son gave me a copy of The Evolution of Beauty, How Darwin's Forgotten Theory of Mate Choice Shapes the Animal World--and Us, by Richard O. Prum.  An ornithologist himself, Prum devotes most of his book to the discussion of exotic mating rituals in birds and the last couple chapters to the evolution of human sexual behavior.  In my opinion, the ties between the two are a bit of a stretch.

Mr. Prum points out that Darwin's first book, On the Origin of Species, is renowned for presenting his theory of natural selection but that his second book, The Descent of Man, makes a case for the role of sexual selection in evolution, a theory that has received a cool reception among most evolutionary biologists.  Prum's book, by his own account, is an effort to defend and expand upon Darwin's theory that sexual selection (i.e. mate choice) has long played a significant role in the evolution of animals.  While his data is very thorough and interesting, I fall into the category of what Prum calls neo-Wallacians (those who are inclined to accept the unvarnished adaptive evolution model proposed by Alfred Russell Wallace, Darwin's colleague).

First of all, I think the phrase "Evolution of Beauty" is misleading and actually works against his argument.  While most of us accept the fact that sexual selection has played a major role in the evolution of intelligent hominids (i.e. humans), physical appearance is but one of many factors in the selection of a mate (a point that Mr. Prum thoroughly discusses himself).  To suggest that female birds choose mates based solely on the beauty and complexity of the males' mating displays is to imply that they are capable of subjective choice and that other factors are not involved.  In the end, the concept of aesthetic evolution seems to simplify a very complex process that, most naturalists believe, is devoted solely to the propagation of one's genome.  Nevertheless, I recommend that you read Prum's book and decide for yourself.