The Panda’s Thumb by Stephen Jay Gould Page A

contains latest capacities which are useless to him in his earlier condition.
    Finally, if our higher capacities arose before we used or needed them, then they cannot be the product of natural selection. And, if they originated in anticipation of a future need, then they must be the direct creation of a higher intelligence: “The inference I would draw from this class of phenomena is, that a superior intelligence has guided the development of man in a definite direction, and for a special purpose.” Wallace had rejoined the camp of natural theology and Darwin remonstrated, failed to budge his partner, and finally lamented.
    The fallacy of Wallace’s argument is not a simple unwillingness to extend evolution to humans, but rather the hyper-selectionism that permeated all his evolutionary thought. For if hyper-selectionism is valid—if every part of every creature is fashioned for and only for its immediate use—then Wallace cannot be gainsaid. The earliest Cro-Magnon people, with brains bigger than our own, produced stunning paintings in their caves, but did not write symphonies or build computers. All that we have accomplished since then is the product of cultural evolution based on a brain of unvarying capacity. In Wallace’s view, that brain could not be the product of natural selection, since it always possessed capacities so far in excess of its original function.
    But hyper-selectionism is not valid. It is a caricature of Darwin’s subtler view, and it both ignores and misunderstands the nature of organic form and function. Natural selection may build an organ “for” a specific function or group of functions. But this “purpose” need not fully specify the capacity of that organ. Objects designed for definite purposes can, as a result of their structural complexity, perform many other tasks as well. A factory may install a computer only to issue the monthly pay checks, but such a machine can also analyze the election returns or whip anyone’s ass (or at least perpetually tie them) in tic-tack-toe. Our large brains may have originated “for” some set of necessary skills in gathering food, socializing, or whatever; but these skills do not exhaust the limits of what such a complex machine can do. Fortunately for us, those limits include, among other things, an ability to write, from shopping lists for all of us to grand opera for a few. And our larynx may have arisen “for” a limited range of articulated sound needed to coordinate social life. But its physical design permits us to do more with it, from singing in the shower for all to the occasional diva.
    Hyper-selectionism has been with us for a long time in various guises; for it represents the late nineteenth century’s scientific version of the myth of natural harmony—all is for the best in the best of all possible worlds (all structures well designed for a definite purpose in this case). It is, indeed, the vision of foolish Dr. Pangloss, so vividly satirized by Voltaire in Candide— the world is not necessarily good, but it is the best we could possibly have. As the good doctor said in a famous passage that predated Wallace by a century, but captures the essence of what is so deeply wrong with his argument: “Things cannot be other than they are…. Everything is made for the best purpose. Our noses were made to carry spectacles, so we have spectacles. Legs were clearly intended for breeches, and we wear them.” Nor is Panglossianism dead today—not when so many books in the pop literature on human behavior state that we evolved our big brain “for” hunting and then trace all our current ills to limits of thought and emotion supposedly imposed by such a mode of life.
    Ironically then, Wallace’s hyper-selectionism led right back to the basic belief of the creationism that it meant to replace—a faith in the “rightness” of things, a definite place