Features: November 2005

Print

Email

In the case of fossils, today’s biologists are more fortunate than Darwin was in having access to beautiful series of transitional stages: almost cinematic records of evolutionary changes in action. Not all transitions are so attested, of course—hence the vaunted gaps. Some small animals just don’t fossilize; their phyla are known only from modern specimens: their history is one big gap. The equivalent gaps for any creationist or intelligent-design theory would be the absence of a cinematic record of God’s every move on the morning that he created, for example, the bacterial flagellar motor. Not only is there no such divine videotape: there is a complete absence of evidence of any kind for intelligent design.

Absence of evidence for is not positive evidence against, of course. Positive evidence against evolution could easily be found—if it exists. Fisher’s contemporary and rival J.B.S. Haldane was asked by a Popperian zealot what would falsify evolution. Haldane quipped, “Fossil rabbits in the Precambrian.” No such fossil has ever been found, of course, despite numerous searches for anachronistic species.

There are other barriers to accepting the truth of Darwinism. Many people cannot bear to think that they are cousins not just of chimpanzees and monkeys, but of tapeworms, spiders, and bacteria. The unpalatability of a proposition, however, has no bearing on its truth. I personally find the idea of cousinship to all living species positively agreeable, but neither my warmth toward it, nor the cringing of a creationist, has the slightest bearing on its truth.

Even without his major theoretical achievements, Darwin would have won lasting recognition as an experimenter.

The same could be said of political or moral objections to Darwinism. “Tell children they are nothing more than animals and they will behave like animals.” I do not for a moment accept that the conclusion follows from the premise. But even if it did, once again, a disagreeable consequence cannot undermine the truth of a premise. Some have said that Hitler founded his political philosophy on Darwinism. This is nonsense: doctrines of racial superiority in no way follow from natural selection, properly understood. Nevertheless, a good case can be made that a society run on Darwinian lines would be a very disagreeable society in which to live. But, yet again, the unpleasantness of a proposition has no bearing on its truth.

Huxley, George C. Williams, and other evolutionists have opposed Darwinism as a political and moral doctrine just as passionately as they have advocated its scientific truth. I count myself in that company. Science needs to understand natural selection as a force in nature, the better to oppose it as a normative force in politics. Darwin himself expressed dismay at the callousness of natural selection: “What a book a Devil’s Chaplain might write on the clumsy, wasteful, blundering low & horridly cruel works of nature!”

In spite of the success and admiration that he earned, and despite his large and loving family, Darwin’s life was not an especially happy one. Troubled about genetic deterioration in general and the possible effects of inbreeding closer to home, and tormented by illness and bereavement, as Richard Milner’s interview with the psychiatrist Ralph Colp Jr. shows in “Darwin’s Shrink,” Darwin’s achievements seem all the more. He even found the time to excel as an experimenter, particularly with plants. Even without his major theoretical achievements, Darwin would have won lasting recognition as an experimenter, albeit an experimenter with the style of a gentlemanly amateur, which might not find favor with modern journal referees.

As for his major theoretical achievements, of course, the details of our understanding have moved on since Darwin’s time. That was particularly the case during the synthesis of Darwinism with Mendelian digital genetics. And beyond the synthesis, Sean B. Carroll details further for the exciting new field of “evo-devo” in “The Origins of Form,” Darwinism proves to be a flourishing population of theories, itself undergoing rapid evolutionary change.

In any developing science there are disagreements. But scientists—and here is what separates real scientists from the pseudoscientists of the school of intelligent design—always know what evidence it would take to change their minds. One thing all real scientists agree upon is the fact of evolution itself. It is a fact that we are cousins of gorillas, kangaroos, starfish, and bacteria. Evolution is as much a fact as the heat of the sun. It is not a theory, and for pity’s sake, let’s stop confusing the philosophically naive by calling it so. Evolution is a fact.