Dr. Dawkins's starting point was the idea that the gene, not the individual, is the basic unit on which natural selection acts. The gene's behavior is most easily understood by assuming its interest is to get itself replicated as much as possible — hence the "selfish" gene of the title.
But genes cannot exist independently. They must cooperate with many other genes in creating vehicles (like ourselves) that are good at getting them replicated.
The primary goal for Dr. Dawkins was to explain the recent work of other biologists, notably George Williams's critique of group selection, William D. Hamilton's theory of kin selection, John Maynard Smith's concept of evolutionarily stable strategies, and Robert L. Trivers's analysis of the intrafamily competition between siblings and between parent and child.
Dr. Hamilton, who died in 2000, is now regarded as one of the most important evolutionary biologists since Darwin. But 30 years ago he was almost unknown, even to specialists, because his insights were expressed in mathematical form.
Dr. Hamilton's chief insight was the solution of a problem that Darwin himself had spotted as potentially fatal for his theory, that of altruistic individuals who sacrifice their lives for the good of their colony, hive or kin. How can a genetic basis for altruism ever evolve, given that an altruist's genes must surely become less common as he diverts resources from helping his own progeny to fostering the survival of others?
Dr. Hamilton showed that it all makes sense when one considers that an individual is not the only carrier of his genes. The very same genes, or at least half of them, are carried by each of an individual's siblings, with lesser fractions shared by uncles, aunts, nephews and nieces. For an altruist to help these relatives survive and propagate their genes is almost as good as propagating his own genes. Once the gene is considered as the unit of selection, it is clear how genes for altruism can spread.
Dr. Dawkins fastened on the idea of the gene as the focus of natural selection and set out in "The Selfish Gene" to restate the new work of Dr. Hamilton, Dr. Trivers and Maynard Smith in these terms. "What he does," the biologist John Krebs writes in this anthology, "is to reanalyze or reinterpret the findings of others with such excoriating rigor, depth and clarity that he uncovers new ideas and ways of thinking."
Dr. Grafen, a biologist and the co-editor, says the exposition of these ideas in the Dawkins book "established a single conceptual framework within which old and new ideas in adaptionism could be understood."
Edward O. Wilson drew on many of the same ideas in his book "Sociobiology," published in 1975, a year before "The Selfish Gene." But "Sociobiology" was a work of synthesis, showing how social behavior across the realm of animal species could be understood in evolutionary terms, whereas Dr. Dawkins's approach was more theoretical. "The Selfish Gene" is "an attempt to convey the underlying logic of a particular type of reasoning, rather than representing a broad overview," Ullica Segerstrale writes in a comparison of the two books.
Despite a fond appreciation in this volume from his local cleric, the bishop of Oxford, Dr. Dawkins has become known to a wider public as a rationalist and a vocal atheist with little time for forms of religious obscurantism like creationism. Mr. Pullman, whose science fiction attacks traditional notions of God, hails Dr. Dawkins as "a ferocious and implacable opponent of those who water the dark roots of superstition."
Though composed of essays that are mostly by Dr. Dawkins's admirers, this book presents a vivid picture of how one man, by force of rigorous analysis and clear writing, taught a generation of biologists how to think about evolution.
On September 25th of this year, "The God Delusion" by Dr. Richard Dawkins will be released.
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