Niles Eldredge ranks as one of the best science writers among professional scientists, in my opinion.1 What I like about Eldredge is that he does not disguise his biases by ignoring all those who disagree with him. Instead, he tries to explain why his view of biology is correct. In this sense he is like Richard Dawkins, although he differs significantly from Dawkins because he (Eldredge) is better at correctly describing the views of his opponents. Eldredge has written 20 popular books on evolution. Dawkins didn't select anything from Eldredge for The Oxford Book of Modern Science Writing. I can't imagine why.
The first example of Eldredge's writing is from Darwin: Discovering the Tree of Life published in 2005. You'll soon see why I choose it.
Imagine for a moment, Charles Darwin taking one of his daily walks along his beloved "Sandwalk"—that stretch of Kentish gravel Darwin had built along the rear edge of his property at Down House. Outwardly, things were normal. It is mid-June 1858. Darwin picks up his walking stick and goes out the back door of Down House. He is a middle-aged man of forty-nine years—a man of regular habits. Strolling along the Sandwalk, a path lined with bits of chalk, flint, and the occasional fossil from the local Cretaceous bedrock of southeastern England, he regularly took the air, inspected his grounds—and mulled over his life and work. He often found peace walking along the path that lay between his expansive field and his neighbor's adjoining property. And he occasionally felt that exhilaration that comes when sudden insight pops into the brain—a solution to a nagging problem that often did not even seem to be uppermost in one's mind at the moment. Darwin was a highly intuitive man, a man whose capacity for creative thought was perfectly matched by his rigor in testing his ideas with observation and analysis, de rigueur in the freshly minted practice of modern professional science.The next example is from Eldredge's excellent book Reinventing Darwin: The Great Debate at the High Table of Evolutionary Theory, published in 1995. This is required reading for anyone who wants to understand the controversies in evolutionary theory.
But things were far from normal that day. For one thing, his two-year old retarded child, Charles Waring, was battling scarlet fever and near death. His fifteen-year-old daughter Etty (Henrietta) had diphtheria, and Darwin had already lost his dear Annie seven years earlier. She had been the second child, Emma and Charles's first daughter, her death from tuberculosis in 1851 had removed what little was left of his religious faith. All this was enough to make him upset. Though another son, Francis, was to write many years later that his father hardly knew a day when his health was robust and normal, that June day his stomach must have been in even greater turmoil than usual.
But there was more, far more, upsetting Darwin's stomach that day. For Charles Robert Darwin had lived the past twenty-two years as a man with a secret. And this was not just any old garden-variety secret like a clandestine love affair, or commission of a crime (although he often thought of it in those terms). He had traveled the globe as a young man in the 1830s, gentleman ship's naturalist and companion to the Beagle's captain Robert FitzRoy, and by the time he reached home in late 1836, not quite twenty-eight years old, he was convinced that life had evolved through natural causes. He saw that human beings were no exception: we are part of the spectrum of life along with all other species of animals, plants, and the then largely unknown microbial world.
....
Darwin had finally begun writing his magnum opus, to be entitled Natural Selection, on May 14, 1856. As he trudged along the Sandwalk that June day in 1858, he had already amassed some ten chapters, and there was still a long way to go. He was cramming in virtually all the examples he had found in his life that supported his ideas: observations he had made as long ago as the Beagle voyage in the 1830s; analysis by experts of some of the plants, animals, and fossil he had brought back from that epic voyage; but also assorted facts on natural history that he had amassed over the past twenty years from the newly emerging scientific literature—and not least, from the dozens of contacts he had made through correspondence with botanists, zoologists, geologists, and plant and animal breeders throughout the world.
His correspondents included a young man named Wallace who, in part modeling himself after Darwin, had been studying the fauna and flora of the far-flung islands of what are now Malaysia and Indonesia. Darwin had written Wallace, encouraging him to pursue his work, including his thoughts on species.
But, prodigious as this fledgling manuscript on Natural Selection had already become, it was too little, too late. What was bothering Darwin most that June day in 1858 was the arrival a few days before, of yet another letter along with a manuscript from that far-off naturalist and specimen collector, Alfred Russel Wallace. With it came a fresh round in Darwin's own personal "struggle for existence." For Wallace had truly scooped him—outlining a theory of natural selection (though he didn't call it that) so well that Darwin later said he could hardly have written a beter abstract of his ideas himself.
Eldredge claims, correctly, that the dominant paradigm of the late twentieth century was an over-emphasis on natural selection acting on individuals (or genes). Those who accept this point of view are called Ultra-Darwinians. Richard Dawkins and John Maynard Smith were the ringleaders. The ultra-Darwinians dominated the High Table and only reluctantly invited their opponents to visit on special occasions.
The grand mistake, the cardinal sin that rightly carries automatic suspension of seating privileges at that High Table, is to suggest a theoretical proposition that assumes that the neo-Darwinian paradigm is somehow erroneous. Theories that claim, in some fundamental sense, to be alternatives to the neo-Darwinian paradigm bear an immense (and I believe insurmountable) burdon of proof on their metaphorical shoulders.
Ultra-Darwinians who people the following chapters are fond of accusing their opponents of precisely that crime.: opposing the core of the neo-Darwinian paradigm. That's precisely what Fairfield Osborn did with his theory of "aristogenesis" in the 1920s, and that, too, is the original sin of Richard Goldschmidt. But that's not what the latter day arrivistes at the Table are doing. We are making the milder, far more defensible, claim that one cannot simply take the neo-Darwinian paradigm and extrapolate it all across the board. We simply do not believe in attributing population-level phenomena to such disparate entities as species, higher taxa, social systems, and ecosystems. And that's precisely what the ultra-Darwinians have been up to, claiming all the while that they've actually demonstrated the truth of what was in reality assumed all along: that the neo-Darwinian paradigm of the workings of natural selection within populations is necessary and sufficient to explain evolutionary history. We naturalists agree that it is necessary. But it isn't sufficient.
Naturalists argue that ultra-Darwinians look endlessly at the minutia of population biology, periodically glancing up to apply their principles across the board in simplistic and generally unrealistic ways. Never shy, the ultra-Darwinians persist in telling anyone who will listen that our naturalists' attempts to formulate theoretical propositions on the nature of the evolutionary process are overwrought failures.
It sounds like George Simpson's story of geneticists versus paleontologists all over again. But there has been progress, within both the ultra-Darwinian and modern versions of the naturalist camps. The problem is reconciling the two. Anyone not seated at (or in the immediate vicinity of) the High Table would surely be reminded of the blind men and the elephant. And while the spirit of the present enterprise remains argumentative, I share George Simpson's conviction (and Maynard Smiths' sometime view) that surely someday, somehow a genuine rapprochement will emerge. One day evolutionists will be able to dine in relative harmony at the High Table.
1. Gould was better when he was alive.
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