The Evolution of Darwinism
by DAVID HAWKES
Popular perception notwithstanding, the theory of natural selection was accepted by every serious evolutionist long before Darwin. Earlier scientists interpreted it as the clearest possible evidence for intelligent design of the universe. William Paley's Natural Theology (1802), for example, employs the famous image of the "great watchmaker" to account for the perfect adaptation of creatures to harmonious ecosystems. Darwin's innovation, which may appear small but is in fact immense, lay in his claim that natural selection is the only cause of evolution.
In one sense, this was merely a change of emphasis: The impulse of pre-Darwinian evolutionists, faced with incontrovertible evidence of natural selection, had been to ask why it occurred. They sought after the "final cause" of evolution, and they found it in the proposal of an intelligent designer. But one of the essential principles of modern science is that such final causes are unknowable. Science must limit itself to "efficient" or "material" causes; it must not ask why things happen, but how. Darwin applied this principle to evolution. Whereas his predecessors had seen the adaptation of organisms to their environment as the effects of design, Darwin saw the physical development of creatures as the sole cause of evolution. The great watchmaker had been overthrown.
As Stephen J. Gould (who died as this issue was going to press) shows in The Structure of Evolutionary Theory, Darwin's breakthrough was essentially methodological. Darwinism is what you get when you focus on the micrological details, resolutely refusing to lift your eyes to the level of the whole. Over the course of the nineteenth century, this methodological sine qua non for scientific investigation was imposed on every discipline, but it originated in the "dismal science" of economics. The "political economy" of Adam Smith began from the material actions of individuals in pursuit of their own selfish ends, and extrapolated from this micrological level to abstract generalizations about the economy as a whole.
What Smith calls "the economy" is thus an amalgamation of all the self-interested actions of individuals, and precisely the same is true of what Darwin understood as "evolution." In fact, Darwin consciously and deliberately imported Smith's economic methodology into biology in order to refute natural theology's argument from design. As Gould baldly puts it, "the theory of natural selection is, in essence, Adam Smith's economics transferred to nature." He is reluctant to dwell too long on this kinship, no doubt because he understands the severity of the threat it poses to Darwinism's pretensions to objectivity. Gould's ally and sometime collaborator Richard Lewontin has criticized him for such reticence in several exchanges first published in the New York Review of Books. Lewontin has called Gould's work "curiously unpolitical" for failing to draw out the implications of "the overwhelming influence of ideology in science." For Lewontin, "Darwin's theory of evolution by natural selection is obviously nineteenth-century capitalism writ large," and attempts to press it into the service of psychology are "pure reification."
The distinguishing theoretical characteristic of both Darwin and Smith is reductionism--they reduce all knowledge to the level of the individual. As Gould notes, "The rebuttal of the former centerpiece of natural history--the belief that organic designs record the intentions of an omnipotent creative power--rests upon the radical demotion of agency to a much lower level, devoid of any prospect for conscious intent, or any 'view' beyond the immediate and personal." Today, technological progress has enabled evolutionists to carry Darwin's reduction a stage further. The smallest individual Darwin could study was the organism, but it is now possible to analyze the behavior of the gene. People like Richard Dawkins now claim that evolution is driven not by competition between individual organisms, but by struggles among genes.
Many evolutionary biologists keep a guilty silence regarding the ethical implications of their theory, but Dawkins positively revels in dehumanization. His imagery dwells lasciviously on the mechanical--our bodies are merely "lumbering robots," or "survival machines" for genes. His infamous book The Selfish Gene (1976) abounds in brazen antihumanist provocations: "I am treating a mother as a machine programmed to do everything in its power to propagate copies of the genes which reside inside it." Nor does mechanization stop with the body; evolutionary psychology views the mind itself as a machine, reducing our thoughts and ideas to the chemical reactions that accompany them. Dawkins has even propounded a theory that the history of ideas follows rules analogous to competitive gene selection, reducing dialectic to a tedious and pointless struggle between what he calls "memes." Lately he has taken to writing letters to the British press, suggesting that Osama bin Laden and George W. Bush will be enlightened if they "study memes."
The idea that genes determine all social behavior, that human beings are machines, evidently strikes a chord in the Western popular mind. Postmodernist works such as Donna Haraway's "A Cyborg Manifesto" celebrate the "posthuman" from what their authors apparently regard as a radical perspective, while the theoretical texts of Michel Foucault and Jean-Francois Lyotard advocate a micrological materialism that excludes on principle any interest in "totalizing grand narratives." As John Dupré has recently remarked, this "tyranny of the microscopic" really constitutes an "intellectual pathology" whose significance is sociological rather than scientific. Gould swats Dawkins away easily enough--sardonically appropriating his vocabulary to dismiss his theory, cruelly but fairly, as an "impotent meme"--but he does not explain why such theories have come to seem plausible to many in the general public. To examine that, we have to back up about 65 million years.
Reptilia served as Exhibit A then. Imagine Triceratops glancing up from its grazing to notice a seven-mile-wide asteroid descending rapidly toward its head. Triceratops had not expected this. Nature had prepared it for the expected; it could expect to spend a great deal of time fighting with Tyrannosaurus rex, for example, and was formidably well-equipped for that purpose. But natural selection had not prepared it to withstand a direct hit from a piece of rock a league long.
The lump of stone that crashed into what is now the Yucatan Peninsula ended the Cretaceous Period by showering the earth with fire and brimstone, thus destroying 70 percent of living species, including almost all the dinosaurs. This was something of a spanner in the works of natural selection, from which it may not recover. The implications of this catastrophe, conclusive evidence for which was discovered only in 1980, have yet to be fully assimilated by evolutionary theory. For most of the twentieth century, orthodox Darwinists held that natural selection--the competitive adaptation of individual organisms to their environment--was the exclusive motor of evolutionary change. Now they must qualify this dogma, but it is proving a laborious process.
Many scientists remain convinced that catastrophic change is the exception. If it weren't for that pesky asteroid, they gripe, natural selection would have continued unabated. They note that natural selection will always work ceteris paribus--that is, other things being equal, under the controlled laboratory environment in which modern scientists conduct their experiments. It will work, that is to say, in the absence of the unexpected. But don't we know from experience that the unexpected happens all the time, and occasionally with catastrophic consequences?
The "K-T event," as the asteroid strike is known, casts suspicion on the doctrinaire claim that evolution is solely the result of the competitive adaptation of individual organisms to their environment. It indicates that the external constraints under which adaptation occurs must inevitably exert an influence on the course of evolution. And it raises the possibility that random, "chance" events play at least as significant a role as the incremental, purposive process of natural selection.
Although it represents a mortal threat to mainstream Darwinism, the theory of catastrophic evolution is quite consistent with Stephen Jay Gould and Niles Eldredge's epochal discovery of "punctuated equilibrium." Punctuated equilibrium, or "punk-ek," holds that evolution does not take place incrementally but rather in spurts that are divided by long periods of stasis. It departs from Darwin by implying that natural selection by competition among individual organisms cannot be the exclusive cause of evolutionary change, since such competition does not pause for periods of equilibrium.
Darwin is often thought to have rescued the history of life from the superstitious fantasies of religion, by basing his theory on good, solid, empirical evidence. But, as Gould and Eldredge noticed, the empirical evidence does not indicate that evolution proceeds by incremental, incessant natural selection, as Darwin claimed. In fact, the empirical evidence indicates quite the opposite. When we look at the living species around us, we do not find a continuum of creatures in infinitesimally graduated stages of evolution. We find, instead, clearly distinct species. We find the same when we look at the fossil record; paleontology testifies that evolutionary stasis is the norm, and that change takes place in abrupt bursts, as though suddenly spurred forward by some external stimulus.
One of the many fascinating questions raised in Gould's The Structure of Evolutionary Theory is why Darwin did not see this. Why did he insist on attributing sole determining power to natural selection in defiance of the evidence? His own explanation was that the fossil record gives a false impression because it is radically incomplete. But this does not alter the fact that natural selection is an imposition on the available evidence, a bold reading against the grain. Did Darwin nod? Why was he so convinced that all evolution is caused by natural selection among individual organisms in competition with one another?
Gould does not explain this, almost certainly for a very interesting reason: He has often been accused, by sociobiologists and orthodox Darwinians, of handing ammunition to creationists. There is no room for an intelligent designer in a universe formed entirely through relentless competition between selfish individuals, but because it allows that external factors may influence evolution, the theory of punctuated equilibrium is not incompatible with theories of intelligent design--a fact that has caused no small embarrassment to its authors. The charge of neocreationism is deeply unfair--Gould testified against creationism in landmark court cases and ridiculed it mercilessly in his writing. He opposed intelligent design on the grounds that it is "theology" and not "science." In this book, obviously intended as his legacy to scientific posterity, Gould repeatedly and emphatically protests that no matter how many revisions and qualifications he may impose upon Darwin, he remains a faithful follower of the great man. In a rare and revealing mixed metaphor, he claims to have retained "the guts of the machine," and he uses a cumbersome simile involving a piece of coral to argue, again and again, that his own work is merely an "addition" to Darwin.
That is rubbish, and Gould must have known it. The Structure of Evolutionary Theory is an "addition" to The Origin of Species in the same sense that Capital is an "addition" to The Wealth of Nations. Gould certainly built upon Darwin's work, assuming its premises as his own and erecting his own theory on the foundation of a meticulous analysis of the original texts. But there comes a stage in the construction at which, in fulfillment of the dialectical law, quantitative change becomes qualitative change, and the extension to the edifice deserves to be called a new building.
Despite (and because of) his vehement denials, I believe that Gould reached that stage. His theory is more than a supplement to Darwinism, it is an alternative view, a paradigm shift. Gould has deprived natural selection of the exclusive role Darwin assigned to it, using the most unimpeachable logic and the most scrupulous empirical research.
Gould obviously liked to limit the destructive impact of his criticism to distortions of the founder's aims. But Darwin cannot so easily be exonerated--Gould himself admits that the work of Dawkins constitutes "a furthering and intensification of Darwin's intent." Indeed, Gould often refers to theorists of gene selection as "ultra-Darwinists" or "Darwinian fundamentalists," because they take the master's reductionist method to the logical conclusion permitted by modern technology. Gould would have been mortified to hear it, but his own interpretation suggests that, were Darwin alive today, he might be Richard Dawkins.
Traditional creationism is based on a literal reading of Genesis and represents no intellectual danger to Darwinism. The recent advocates of "intelligent design," however, demand to be taken a little more seriously because of their recent political and pedagogical successes; they admit to the apparent age of the earth as established in the geological record, for example, and accept the fossil record as evidence of species change. Hard-fought cases involving the boards of education of Kansas (1999) and Ohio (2002) have established a new beachhead for intelligent design in the public mind, while simultaneously throwing a shadow on natural selection's claim to be the exclusive motor of evolutionary change.
The idea that schools in Kansas might depart from Darwinist orthodoxy induced apoplexy among the commissars of science. John Rennie, editor of Scientific American, urged colleges to be skeptical of applicants from Kansas: "If kids in Kansas aren't being taught properly about science, they won't be able to keep up with children taught competently elsewhere. It's called survival of the fittest. Maybe the Board of Education needs to learn about natural selection firsthand." In an edition of the American Spectator, a leading theorist of intelligent design, Michael Behe, professed to be mystified at Rennie's outburst: "What is it about the topic of evolution that drives so many people nuts? Why does a change in a farm state's high school examination policy call forth damning editorials all the way from London, England, and have normally staid editors threatening children?"
The answer is obvious, blindingly so. Behe does not see it because he, like most advocates of intelligent design, approaches the issue from a socially conservative point of view. Much scholarship on intelligent design is sponsored by the Discovery Institute, a Seattle-based foundation that describes itself as "dedicated to exploring and promoting public policies that advance representative democracy, free enterprise and individual liberty," and whose mission statement commits it to boosting the "common sense" of the "free market." It is this commitment, I suppose, that distracts Behe from one of the reasons the American establishment goes "nuts" when the educational privilege of natural selection is threatened: A threat to the exclusivity of natural selection--individual competition--is a threat to market ideology. (Although he tactfully pays it less attention than it deserves, Gould acknowledges the full extent of Darwinism's complicity with Adam Smith. But the alterations Gould introduces into evolutionary theory do not depend on its ideological kinship with classical economics.)
Neither Behe nor his book Darwin's Black Box rate a mention in The Structure of Evolutionary Theory, and Gould's silence on the subject of intelligent design can be regarded as extremely eloquent. He would have denied it, but this book really charts Gould's arduous passage through Darwinism and his emergence on the other side. This breakthrough seems to have been facilitated by his discovery of the literature that Darwin was writing against. Gould blithely informs us that "I had never read [Paley's] Natural Theology straight through before pursuing my research for this book." Lay readers may find this an astonishing confession from the world's leading Darwin scholar, but those familiar with scientists' undiscriminating rejection of metaphysics will be unsurprised. Having forced himself to pick up the book, Gould finds that Paley's primary observation is "undoubtedly correct," and largely accepted by Darwin--nature does indeed indicate exquisite adaptation to environment. The difference lies in the reason Darwin gives for this order in creation. Paley thought it bespoke a benign creator, but Darwin "seems to mock the standard interpretation in a manner that could almost be called cruel" when he introduces the micrological economics of Adam Smith:
as the cruellest twist of all, this lower-level cause of pattern seems to suggest a moral reading exactly opposite to Paley's lofty hopes for the meaning of comprehensive order--for nature's individuals struggle for their own personal benefit, and nothing else! Paley's observations could not be faulted--organisms are well designed and ecosystems are harmonious. But his interpretations could not have been more askew--for these features do not arise as direct products of divine benevolence, but only as epiphenomena of an opposite process both in level of action and intent of outcome: individuals struggling for themselves alone.
Read that last sentence again. What might bring about the triumph of the "opposite process" to "divine benevolence"? Clue: It is not the blind indifference of nature. The history of human thought is hardly silent concerning the struggle between a benevolent deity and a cruel mocker. But Gould shies away from considering the theological implications of his theory with the standard get-out clause: "This book cannot address such a vital issue at any depth."
Many readers will be tempted to respond: "Why on earth not? It's 1,400 pages long!" But Gould was not eager to incur again, in his magnum opus, the tired charge of neocreationism. He does begin to speculate about why the homologous visions of Darwin and Smith should complement each other so conveniently, and he also raises the question of why this connection has come to seem so glaring in recent years. But his uncharacteristic hesitancy reveals his discomfort away from scientific terrain: "I venture these ill-formulated statements about Zeitgeist because I feel that something important lurks behind my inability to express these inchoate thoughts with precision."
Indeed it does. Later in the book, Gould remarks that "the exclusivity of organismal selection...provides the punch line that allowed the vision of Adam Smith to destroy the explicit beauty and harmony of William Paley's world." Absolutely true. But the exclusivity of organismal selection is what Gould denied, too. Is it really accurate, then, to continue calling him a "Darwinist"? At one point, Gould demands that creationists throw in the towel and acknowledge Darwin as "the Muhammad Ali of biology." Ali was undoubtedly a great champion, but his present condition renders Gould's image rather ambiguous. And then, too, the reader is left in some doubt as to whether Gould saw himself in the role of Angelo Dundee or Joe Frazier.