Darwin Turns 200
The gentleman-naturalist who reinvented biology.
Dec 28, 2009, Vol. 15, No. 15 • By DAVID GELERNTER
Darwin is a huge presence in the modern world, in two ways. He was a remarkable thinker, a great scientist, and the most influential biologist in history. He revolutionized the study of nature. He is also a cultural presence. Increasingly he is the venerated image carried in torchlight processions by bands of angry, chanting atheists ("Darwin! Darwin! Darwin!") who dominate the impoverished streets of the intellectual world.
Berra recites the facts, but rarely comments. We know (for example) that Darwin's was an extraordinary mind. Yet he spent eight years in the prime of life studying barnacles. Berra explains why: His eminent colleague Joseph Dalton Hooker had told him that "no one has hardly a right to examine the question of species who has not minutely described many." Darwin had already conceived his big idea of evolution by natural selection, but instead of publishing it, he hunkered down and worked on barnacles. He himself grew colossally bored--but he soldiered on. How could this brilliant scientific virtuoso stifle his imagination for eight years while he focused on nothing but the finger exercises of biology?--playing scales and arpeggios and never one measure of music? Strange. Berra has no comment.
But the main theme comes through loud and clear. Darwin's (and Alfred Russel Wallace's) theory of evolution by natural selection is made to seem simple and inevitable, which it is. Ordinary farmyard breeding produces new variants as a result of deliberate crosses and spontaneous genetic errors, or mutations. When the breeder sees a new variant he likes, he does his best to propagate it; this is "artificial selection." But it's clear also that, regardless of the breeder's plans, certain new variants are more robust than others: are better suited to survive and thrive in the environments in which they live. And left to their own devices, the more robust variants supplant, over time, the less robust varieties.
Given these simple observations, natural selection must happen, and must bring about the gradual transformation, or evolution, of living things. Spontaneous mutations create variant forms of life. Some variants are more robust than others; some are more robust than the original. In a world of limited resources, the better-adapted versions stand a better chance of surviving, thriving, and reproducing. Darwin guessed, further, that natural selection is powerful enough to transform one species into another (or many others)--and also to eradicate a species, leaving the field to its tougher competitors. What scientists have learned from the study of ancient and modern life strongly supports Darwin's guess.
"The theory of evolution," writes Berra in the first sentence of his introduction, "is arguably the greatest idea the human mind ever had," and this sentence is arguably one of the silliest. If you put Darwin next to a Newton or an Einstein, a Beethoven or an Isaiah, he is out of his league and beyond his depth. Treating Darwin as one of the presiding geniuses of human thought is unfair to him; he never asked to be compared to Newton. In fact, thinking back to the barnacle years, the heretical idea tiptoes shyly across the mind that Darwin was not so much brilliant as shrewd. In any case, his ideas have been profoundly influential. Darwinian evolution is the core (the elevator stack) of modern biology, paleontology, and genetics, which have grown up gradually around it. Moreover, Darwin took good care of his family and was generous to his colleagues. He was a gentleman genius.
Nowadays some thinkers question Darwin's role at the center of modern thought. The most impressive accept evolution by natural selection (which is impossible not to accept) but aren't sure that this mechanism is enough to explain nature as we find it.
Some of their qualms are unconvincing. A dissident often cites some marvelously subtle and complex piece of human anatomy (the eye, the hand, etc.), points to the countless millions of exquisitely graduated steps required by natural selection (that blindfolded drunk) in order to reach this goal, notes the staggering improbability of such a sequence of developments happening just by accident, and rests his case.