The Selfish Gene
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The Selfish Gene is a controversial book by Richard Dawkins published in 1976. 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 can be viewed as acting on genes, and that selection on 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). In addition, organisms will tend to evolve towards an evolutionarily stable strategy.
Describing genes with the term "selfish" is not meant to imply that they have actual motives or will—only that their effects can be described as if they do.
A crude analogy can be found in the old joke "A chicken is just an egg's way of making more eggs." Likewise, Dawkins describes biological organisms as "vehicles" used by their genes for making more copies of those genes, regardless of the effect they might have on individuals or species. Obviously, genes that tend to help the organisms they are in to survive and reproduce also improve their own chances of being passed on; so most of the time "successful" genes will also be beneficial to the organism. But there are exceptions: segregation distortion genes, for example, that are detrimental to their host 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. These examples might suggest that there is a power-struggle between those genes and their host. In fact, the claim is that the interests of the organism are redundant, from an evolutionary point of view. (This is where the related concept of the extended phenotype comes into play.)
When looked at from the point of view of gene-selection, many biological phenomena that were difficult to explain in terms of prior models of evolution become easier to understand and explain. In particular, phenomena such as kin selection and eusociality, where organisms act 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. In other words, genes act "selfishly" to increase the number of copies of themselves and for no other reason. This is in contrast to group selection, the dominant theory in evolutionary genetics prior to the 1960s.
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 (who couldn't have explained natural selection in these terms 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 increasingly viewed as extreme. In the last decade, difficulties with the theory of multi-level selection have been overcome and interaction between genes and between organisms as a force in evolution has again become a topic of research.
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
| Richard Dawkins |
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| 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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es:El gen egoísta ja:利己的遺伝子 no:Det egoistiske genet pt:O Gene Egoísta hu:Az_önzÅ‘_gén