Anyone who has ever been to the zoo and seen a peacock strutting around, displaying the full regalia of his tail feathers has surely been amazed at the lengths that the male of a species will go to try to get laid. But the peacock is no accident of nature. His tail feathers have evolved over millions of years to become bigger, brighter, and more hypnotizing because in each generation of peacocks, those with the most spectacular plumage were the ones who wound up having hot dates with the most peahens.
Although scientists have tried valiantly to come up with alternate explanations for why peacocks have developed such a sensationally cumbersome tail, none makes as much sense as Darwin’s theory of sexual selection. Lugging around a huge iridescent tail does not seem to be an advantage in any other way for the poor peacock. It is a glaring advertisement to his predators, and its heavy and unwieldy nature makes it much more difficult for him to escape from them once he’s been spotted. The tail also requires a great deal more energy to grow and to keep clean and attractive. But as long as more chicks dig his tail, the advantage of beauty will be enough to outweigh the disadvantage of the increased likelihood of becoming a tiger’s lunch.
Some scientists believe that there is a close parallel between the peacock’s tail and an organ of man that has also grown bigger and bigger in order to be more attractive to the opposite sex. In no other species has this organ grown large and unwieldy to the point where it becomes more likely that it will get its owner killed. It may surprise you to find that man’s most important sexually selected organ is our brain. As evolutionary psychologist Geoffrey Miller argues, our brain “is largely a courtship device to attract and retain sexual mates. Its specific evolutionary function is to stimulate and entertain other people, and to assess the stimulation attempts of others.” Miller believes that many aspects of human behavior, such as art, music, and dance, have little survival value. Yet surveys of both men and women consistently place such traits as a sense of humor, creativity, intelligence, and interesting personality above even wealth and beauty in lists of what we value most when searching for a mate. What most humans find sexy and alluring are people with fantastic brains.
Each successive generation of our ancestors had to become a little more clever in order to outwit their competitors in the mating pool. They needed to remember more interesting stories, sing more beautiful songs, or tell funnier knock-knock jokes. Some members of every generation would come up with new tricks for attracting the opposite sex: more alluring make-up, fashionable clothing, intriguing games, romantic poetry, delicious cooking skills, anything they could use their increasingly heavy brains to think of.
Our brains grew so large that, unlike in any other primate species, they often killed our mothers during childbirth. Naturally, these branches of the family died off, leaving only the wide-hipped mothers who were able to bear our big-brained ancestors. Why do men love wide-hipped women so much? Because we unconsciously know they will provide plenty of room for our big-brained children. Shake-shake your bootie!
Unfortunately, one of the side effects of having such a big sexy brain is that it seems increasingly likely to get us all killed. Unlike the peacock, who has to worry about only a few predators eating it before its time, every man must consider the possibility that any one of billions of his fellow men might come up with some harebrained scheme that will end all life as we know it. Besides using our brains for the admirable goal of finding the healthiest, funniest, most interesting mate, we have also used it extensively to figure out new and better ways to kill off our competition. This competition has included practically every other species on the planet, as well as man himself.
But the fact that witty, creative people turn us on has also led to some wonderful side effects. For every George Clooney and Marilyn Monroe, we’ve also inherited an Albert Einstein and Madame Curie. For every surgeon doing breast implants or facelifts there are hundreds repairing broken bones. Since we’re stuck with this relic of evolution we may as well do our best to enjoy it. So chill the champagne, light the candles, put on some romantic music, and have an all night intertwining of your hearts, your bodies, and, especially, your minds.