Their scientific rivalry describes the different ways we conceptualize life, randomness, and science itself.
On my recent travels abroad, I got a copy of Dawkins Vs. Gould: Survival of the Fittest by Australian philosopher, author, and educator Kim Sterelny. It’s a brief but comprehensive overview of the rivalry between English ethologist Richard Dawkins and American paleontologist Stephen Jay Gould. Sterelny wrote it prior to Gould’s death in 2002, so the conflict was still current at the time of this book’s publication. If it seems odd that I say Gould ‘thinks’ or ‘proposes’ things more than a decade after his death, it’s just in the context of this book and its argument.
Sterelny is consciously trying to avoid caricaturing either writer’s opinions, so the text is full of fair and quite nuanced descriptions of the major points of conflict between Dawkins and Gould. I think the book is fodder for many fascinating discussions, but I think it would be best if I concentrate on three separate categories of disagreements. In Part 1, I’ll discuss the different way each conceptualizes natural selection in evolution. In Part 2, I’ll discuss the conflict between their views about how life on Earth has developed. And in Part 3, I’ll talk about the differences in the way each defines science itself, its nature, aims, and limitations.
Obviously there’s a lot of overlap between their views. They’re both atheists who have no room for supernatural explanations for natural phenomena. They’re both Darwinists who give old man Darwin huge props for his ingenuity and thoroughness. They both view science as an important human endeavor. However, there are truly fundamental disagreements in how each approaches important matters in the scientific and philosophical contexts of evolutionary theory.
The most fundamental disagreement between Gould and Dawkins in terms of evolutionary theory concerns natural selection. They both realize that Darwin revolutionized biology by turning natural selection from a conservative force that eliminated outliers to a creative mechanism that accounted for biological change. They both agree that natural selection is an important part of species evolution. So what’s their beef?
The disagreement here is one of emphasis. Dawkins (unless he’s being absolutely magnanimous) declares that natural selection is virtually synonymous with evolution. For him, the cumulative effect of countless rounds of natural selection is the sole explanation for the development of life on Earth. In The Blind Watchmaker, he even wrote, “Chance is a minor ingredient in the Darwinian recipe, but the most important ingredient is cumulative selection which is quintessentially nonrandom.”
Gould takes issue with this view, which he calls adaptationism or pan-selectionism. He points out that Darwin himself battled the misconception of his work that made natural selection the be-all and end-all of biological change. Gould and geneticist Richard Lewontin published a controversial paper in 1979 called The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme, in which they criticized the tendency of evolutionary biologists to propose adaptive stories for traits or structures in lieu of doing rigorous research into the evolutionary history of those traits. Gould and Lewontin emphasized that not all evolutionary change was adaptive, and the tendency to characterize all traits and structures as adaptations boils down to fact-free storytelling.
A World of Possibility?
Sterelny describes the difference between Gould and Dawkins here as different opinions on the range of possibilities open to selective processes:
Selection acts only on variation generated in a lineage. The developmental biology of a lineage determines the range of variation. That developmental biology is the result of that lineage’s evolutionary history. So the variation that is available to selection in a lineage is determined by its history: its history constrains its future evolutionary possibilities. Perhaps a chimpanzee with a powerful and prehensile tail would be fitter than chimps as we find them. For it would be well suited both to life in the trees and on the ground, harvesting the best of both worlds. Even so, if no tailed variants were thrown up in ancestral chimp populations, selection cannot make such a chimp. The evolutionary trajectory of a population is hostage both to selection and the supply of variation. […]
Why are there no centaurs? Perhaps they would be too expensive to run, or too subject to back pain. But perhaps six-limbed mammals have simply never been available for selection. Dawkins is inclined to make a selectionist bet on these issues. His guess is that, over the long run, the space of evolutionary possibilities open to a lineage is rich. Hence the history of the lineage is largely determined by selection making some of these possibilities actual. Selection determines, for instance, that actual mussel shells are strong, thick, and low. [Sterelny has just discussed Dawkins’ argument “The Museum of All Possible Shells” from his book Climbing Mount Improbable.] Gould, on the other hand, is inclined to bet that the array of possibilities open to a lineage is tightly restricted, often to minor variants of its current state. Hence, its history is largely shaped by the events that set the envelope of possibilities; for instance, the events that determined that vertebrates have at most four limbs.
The most striking difference between Dawkins and Gould in terms of the way they approached natural selection is in their tolerance for the idea of sociobiology, or evolutionary psychology. Dawkins implicitly accepts that human behavior patterns can be adaptations, and has always pushed the idea of memes (ideas that human societies copy and perpetuate) to explain cultural evolution. Gould strongly objects to applying adaptationist thinking to social and cultural phenomena, and claims that cultural and Darwinian evolution “differ profoundly.”
So that’s a broad overview of the dispute between these two thinkers about natural selection and evolution. Are these fundamental differences in the definition of Darwinian theory, or are they squabbles over irrelevant details? Is this a legitimate scientific dispute, or is it more emblematic of the ideological differences between the individualistic liberal Dawkins and the more Marxist Gould?
Next: Dawkins and Gould face off over the development of life on Earth.