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A Passion for Evolution

Most science popularizers are not controversialists. Most see their task as a simple explanation of science that already sits, tedious and unread, in textbooks. The job of making science appealing to the layman often encour-ages breathless tales of high-tech adventure (a genome project, say) and almost always entails a good deal of dumbing down. Richard Dawkins’s work has never fit this mold. His books on evolution have featured ideas that were only then making their way into textbooks and he has never hesitated to offer his own (sometimes radical) extensions of these ideas. But most important, his books have emphasized ideas, and they have been offered in their fullness, without dumbing down. In the course of his work, Dawkins has also not shied from controversy. He has publicly battled both fellow scientists and religious leaders, and he has made enemies.

Although Dawkins is an extraordinarily popular and prolific writer—his books include The Selfish Gene (1976), The Extended Phenotype (1982), The Blind Watchmaker (1986), and Climbing Mount Improbable (1996)—his shorter pieces have never been collected until now. The thirty-two essays bundled in A Devil’s Chaplain appeared originally in newspapers or magazines, or as forewords to books or as eulogies; a few are previously unpublished. Because these essays span nearly all of Dawkins’s career so far—the earliest appeared in 1978 and the latest in 2003—they provide a sort of chronicle of his thinking. And because each group of related essays is preceded by a short new introduction, we learn where Dawkins now stands on a number of issues.

A Devil’s Chaplain reveals several things about Dawkins, some surprising and some not. Not surprisingly, the book confirms his reputation as a superb prose stylist, perhaps the best popularizer of science working. Whether you agree with him or not, you are never unsure of his meaning and his writing is, in places, stunning. Also not surprisingly, A Devil’s Chaplain includes hard-hitting pieces that attack several of Dawkins’s traditional targets: pseudoscience (New Age crystals get it here), postmodernist obscurantism (he’s fond of Alan Sokal’s Social Text hoax), and religion.

As for the surprises, the biggest is Dawkins’s breadth. For those who know him only as a champion of Darwinism, it’s news to see that he has written a number of beautiful pieces on the Africa of his youth, as well as passionate essays decrying educational systems that sacrifice love of learning for test performance. And his position on several controversial issues may not be what you expect. Though Dawkins is sometimes viewed as soft on sociobiology, A Devil’s Chaplain includes a superb polemic against the errors inherent in human genetic determinism and another against the evils of social Darwinism. The book also features several surprisingly moving eulogies to departed colleagues, including one to Stephen Jay Gould, with whom Dawkins often sparred.

Despite his breadth, Dawkins is surely best known for three things: his defense of the selfish gene view of biological evolution, his invention of the selfish meme view of cultural evolution, and his animosity toward religion. A Devil’s Chaplain takes up each of these themes, some more convincingly than others.

1.

Dawkins has spent much of his career defending a particular view of Darwinism. This so-called selfish gene view grew out of work in the 1960s by George Williams and William Hamilton. While Darwin argued that evolution involves a kind of survival of the fittest, Hamilton, Williams, and their heirs argued that it’s the fittest gene that matters, not the fittest organism. To see what this means, consider an example. When a small bird spots a hawk overhead it will often issue an alarm call, warning its flock-mates of the predator’s presence. The odd thing is that this behavior—which we’ll assume is instinctive, that is, genetically based—is “altruistic.” By sounding the alarm, a bird may well save its flock-mates but it simultaneously calls attention to itself, increasing the odds that it will be attacked by the hawk. How could such a behavior evolve?

If you think of Darwinism in traditional terms—as competition among different organisms—the answer isn’t obvious. A bird who sounds a call (and so perhaps gets eaten) is unlikely to have more offspring than a bird who keeps quiet (and so probably avoids getting eaten). And having more offspring is what Darwinism was supposed to be all about. But if you think of Darwinism in selfish gene terms—as competition among different genes—the answer is clearer. A gene that makes a bird emit an alarm may decrease the odds that the calling bird survives but it can increase the odds that the gene for alarm-calling survives. The reason is that the flock-mates who are saved by the alarm are, like all flock-mates, likely to be related to the caller; and relatives, by definition, tend to carry the same genes, including the gene for sounding the alarm. In effect, then, the alarm-call gene is warning—and saving—copies of itself. Those copies just happen to reside in other organisms. The counterintuitive conclusion is that a gene that sometimes causes an organism to sacrifice itself can increase its frequency by natural selection. The alternative kind of gene—one for not emitting an alarm call—can decrease in frequency, since such genes are on average less likely to be passed on to the next generation.1

To Dawkins and other advocates of the selfish gene view, such examples reveal something deep about Darwinism: natural selection acts at the level of competing genes, not competing organisms. It is genes that are engaged in a struggle for existence and we can, therefore, expect them to “selfishly” do whatever they can to increase their representation in the next generation. (The quotes emphasize that genes are not consciously selfish; it’s just that their dynamics look like those of consciously selfish agents.) In the end, the selfish gene view suggests that the properties we see in organisms are those that maximized the survival of genes, not the welfare of organisms. Taken to its logical conclusion, genes begin to seem like manipulators who build organisms in whatever way best serves the genes’ “interests,” whether or not these coincide with the organisms’ interests. Indeed Dawkins spoke of organisms as mere “vehicles” for genes or as “lumbering robots” that were “blindly programmed to preserve the selfish molecules known as genes.” It was this view that he popularized in his first book, The Selfish Gene, and that he continues to defend, though in modified form, in A Devil’s Chaplain.

Dawkins’s defense was (and mostly still is) against Gould. Dawkins and Gould engaged in an extended dispute over “units of selection”: Is the gene the fundamental unit on which natural selection acts or can selection act at other levels too? Gould championed “hierarchical selection,” the idea that selection can act at any level in the biological hierarchy, from single genes to entire ecosystems. He was particularly fond of “species selection,” in which whole species are the target of natural selection. (Species that split into new species faster than, or become extinct slower than, other species will become more common.) To Gould, there was nothing particularly special about the gene level and any claim to the contrary reflected a regrettable misunderstanding of Darwinism. Though Dawkins and Gould disagreed about many other matters, the units of selection debate was particularly protracted and noisy.

By the time of Gould’s death, however, the debate had begun to subside. To some extent, this reflected the fact that evolutionists grew tired of it. To a considerable extent, though, it reflected the fact that Gould grew less vague and Dawkins grew less strident. Gould and his colleagues finally offered a precise definition of species selection, and most evolutionists now accept that natural selection can in principle act at any level in the biological hierarchy. Dawkins admits as much in A Devil’s Chaplain (though in a roundabout way: “Indeed it may, after a fashion…”). But no matter, Dawkins’s real admission came earlier, in The Extended Phenotype, in which he rejected the claim that the selfish gene view represents the right way to think about evolution and took up the claim that it represents a powerful, though not necessarily privileged, point of view. Though this may seem a retreat from the selfish gene line—and in strictly philosophical terms I suppose it is—in scientific terms, it is not.

Powerful new points of view are what science is all about. Most scientists would trade a technically sound but intellectually sterile point of view for a provocative and fertile one any day. And on these more pragmatic grounds there can be no doubt that Dawkins had the edge: the selfish gene view has been exceptionally fertile, providing unexpected insight into everything from the organization of insect societies to the spread of “junk” DNA that has no function. Indeed selfish gene thinking is now orthodox in evolutionary biology and, among many evolutionists, represents a near reflex. It is certainly true that Dawkins’s early rhetoric was sometimes extreme. But it is more true that selfish gene thinking has delivered a number of important insights. The same cannot be said for hierarchical selection, as Gould himself lamented in his final major publication, The Structure of Evolutionary Theory. Indeed while many of us suspect that higher-level selection occurs, the evidence for it is, so far, frustratingly weak.

2.

Dawkins did not stop with biological evolution. At the close of The Selfish Gene he pushed the idea of a selfish replicator in a radical new direction: the Darwinian logic of selfish genes may extend beyond genes. In particular, Dawkins argued that cultural entities like ideas, tunes, and fashions behave in a way that’s analogous to genes: some of these entities, which he called “memes,” spread through a culture faster than others. Certain advertising jingles, for instance, are (annoyingly) catchy and spread among people at a remarkably fast rate: I hear a jingle, I hum it; you hear me hum it, you hum it; and so on. This jingle is therefore a fit meme: it is good at propagating among minds and so can be thought of as increasing in frequency in a population of brains by a kind of cultural natural selection. (Note that a meme, like a gene, can be fit whether or not it’s good for the organism. A jingle isn’t fit because it does anything for me; it’s fit because it spreads fast. Note too that memes have no necessary connection with biologi-cal fitness: a fit meme needn’t boost your production of children.) Dawkins boldly suggested that we might think of cultural evolution as a struggle among replicating memes in the same way that we think of biological evolu-tion as a struggle among replicating genes.

The idea of memes is interesting and there’s probably something to it, at least when taken loosely, as a provocative analogy between biology and culture. But A Devil’s Chaplain makes it clear that Dawkins takes the idea more seriously than this. Though Dawkins seemed at one time to soften on memes, he now insists that he is as enthusiastic as ever. Indeed he is “delighted” that others are now making the meme “a proper hypothesis of the human mind.” Dawkins seems particularly fond of the philosopher Daniel Dennett’s suggestion that memes played a key role in the evolution of the human mind.2 But this stronger version of the meme idea—the notion that memes provide a basis for a real science of culture or mind—has been sharply criticized.

  1. 1

    This explanation of alarm calling is not universally accepted, but it captures the essence of the selfish gene argument.

  2. 2

    Dennett contended that the mind is an artifact created by the activity of memes, all struggling to shape a better habitat for their own propagation (Consciousness Explained, Little, Brown, 1991).

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