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The Selfish Gene is a somewhat controversial book by Richard Dawkins. The phrase "selfish gene" in the title of the book was coined by Dawkins as a provocative way of expressing the gene-centered view of evolution, which holds that evolution is best viewed as acting on genes, and that selection at the level of organisms or populations almost never overrides selection on genes. More precisely, an organism is expected to evolve to maximise its inclusive fitness—the number of copies of its genes passed on globally (rather than by a particular individual). As a result, populations will tend towards an evolutionarily stable strategy. The book also coins the term 'meme', for a unit of human cultural evolution analogous to the gene, suggesting that such "selfish" replication may also model human culture, albeit in a different sense. Memetics has become the subject of many studies since the publication of the book.

Describing genes with the term "selfish" is not meant to imply that they have actual motives or will—only that their effects can be accurately described as if they do. The contention is that the genes that get passed on are the ones whose consequences serve their own implicit interests, not necessarily those of the organism, much less any larger level. Some people find this metaphor entirely clear, while others feel that it is confusing or misleading to ascribe mental attributes to something that is mindless. For example, Andrew Brown writes, "'Selfish,' when applied to genes, doesn't mean 'selfish' at all. It means, instead, an extremely important quality for which there is no good word in the English language: 'the quality of being copied by a Darwinian selection process.' This is a complicated mouthful. There ought to be a better, shorter word -- but 'selfish' isn't it. [1]

A crude analogy can be found in the old saw about a chicken being just an egg's way of making more eggs. In a similar inversion, Dawkins describes biological organisms as 'vehicles', with genes as the 'replicators' that create these organisms as a means of acquiring resources and copying themselves. At the level of organisms, we can see genes as being for some feature that might benefit the organism, but at the level of genes, the sole implicit purpose is to benefit themselves. A related concept here is the extended phenotype, in which the consequences of the genes to the environment outside the organism are considered.

Genes that help the organism they happen to be in to survive and reproduce tend to also improve their own chances of being passed on, so —most of the time— "successful" genes will also be beneficial to the organism. An example of this might be a gene that protects the organism against a disease, which helps the gene spread and also helps the organism. There are other times when the implicit interests of the vehicle and replicator are in conflict, such as the genes behind certain male spiders' instinctive mating behavior, which increase the organism's inclusive fitness by allowing it to reproduce, but shorten its life by exposing it to the risk of being eaten by the cannibalistic female. Another good example is the existence of segregation distortion genes that are detrimental to their host but nonetheless propagate themselves at its expense. Likewise, the existence of junk DNA that provides no benefit to its host, once a puzzle, can be more easily explained. A more controversial example is aging, in which an old organism's death makes room for its offspring, benefiting itself at the cost of the organism.

These examples might suggest that there is a power-struggle between genes and their host. In fact, the claim is that there isn't much of a struggle because the genes usually win without a fight. Only if the organism becomes intelligent enough to understand its own interests, as distinct from those of its genes, can there can be true conflict. An example of this would be a person deciding not to breed because they'd be miserable raising children, even though their genes lose out due to this decision.

When looked at from the point of view of gene selection, many biological phenomena that, in prior models, were difficult to explain become easier to understand. In particular, phenomena such as kin selection and eusociality, where organisms act altruistically, against their individual interests (in the sense of health, safety or personal reproduction) to help related organisms reproduce, can be explained as genes helping copies of themselves in other bodies to replicate. Interestingly, the "selfish" actions of genes lead to unselfish actions by organisms.

Prior to the 1960's, it was common for such behavior to be explained in terms of group selection, where the benefits to the organism or even population were supposed to account for the popularity of the genes responsible for the tendency towards that behavior. This was shown not to be an evolutionarily stable strategy, in that it would only take a single individual with a tendency towards more selfish behavior to undermine a population otherwise filled only with the gene for altruism towards non-kin.

Proponents argue that the central point of the idea, that the gene is the unit of selection, is a more complete and accurate explanation of evolution than Darwin's. (Darwin, however, cannot be faulted for this absence because the basic mechanisms of genetics weren't understood at the time). Critics argue that this view oversimplifies the relationship between genes and the organism. The majority of modern evolutionary biologists accept that the idea is consistent with many processes in evolution. However, the view that selection on other levels such as organisms and populations almost never opposes selection on genes is somewhat more controversial. While naive versions of group selectionism have been disproven, there are now more sophisticated formulations that do make accurate predictions in some cases while speaking of selection at higher levels. Whether this is of any net benefit over a gene-centric view is in some dispute, though. Some biologists have criticised the idea for describing the gene as the unit of selection, but have suggested describing the gene as the unit of evolution, on the grounds that selection is a 'here and now' event of reproduction and survival, while evolution is the long-term trend of shifting allele frequencies^[1].

Another criticism of the book, made by philosophers such as Mary Midgley in her book Evolution as a Religion, is that it discusses philosophical and moral questions that go beyond the biological arguments that Dawkins makes. Dawkins has pointed out that he is only describing how things are under evolution, not endorsing them as morally good; and humanity finally gaining power over the "selfish replicators" is a major theme at the end of the book.

The idea is sometimes mistakenly believed to support genetic determinism. This is incorrect: knowing that an organism carries a particular allele, we might be able to say that the organism is more likely than otherwise to behave in a certain way, but its actual behavior will depend on its environment and its developmental history. In particular, this applies to human organisms; Dawkins is quick to point out that, although we may be influenced by our genes, we are not controlled by them. Even further from Dawkins' concept is the misunderstanding of the idea as predicting (or even prescribing or justifying) that human behaviour must inevitably be "selfish" in a moral or ethical sense.

Bibliography

• The Selfish Gene, Richard Dawkins Oxford University Press, 1976; 2nd edition, December 1989, hardcover, 352 pages, ISBN 0192177737; April 1992, ISBN 019857519X; trade paperback, September, 1990, 352 pages, ISBN 0192860925

References

1. ^ Gabriel Dover, 2000. Dear Mr Darwin. Weidenfeld & Nicholson ISBN 0753811278

Richard Dawkins
Books: The Selfish Gene - The Extended Phenotype - The Blind Watchmaker - River Out Of Eden - Climbing Mount Improbable - Unweaving the Rainbow - A Devil's Chaplain - The Ancestor's Tale
See also: W. D. Hamilton - Williams revolution - atheism - humanism - evolution - Lalla Ward
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