El gen egoï¿½sta extendido [Richard Dawkins] on Cuando Dawkins publicó la primera edición de El Gen Egoísta en , escribió que. : El gen egoista / The Selfish Gene: Las bases biologicas de ( ) by Richard Dawkins and a great selection of similar New, Used . Results 1 – 30 of 38 El gen egoista by Richard Dawkins and a great selection of related books, art and collectibles available now at
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The Selfish Gene is a book on evolution by Richard Dawkinsin which the author builds upon the principal theory of George C. Williams ‘s Adaptation and Natural Selection Dawkins uses the term “selfish gene” as a way of expressing the gene-centred view of evolution as opposed to the views focused on the organism and the grouppopularising ideas developed during the s by W.
From the gene-centred view, it follows that the more two individuals are genetically related, the more sense at the level of the genes it makes for them to behave selflessly with each other. A lineage 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, in a different sense. Memetics has become the subject of many studies since the publication of the book. In raising awareness of Hamilton’s ideas, as well as making its own valuable contributions to the field, the book has also stimulated research on human inclusive fitness.
In the foreword to the book’s 30th-anniversary edition, Dawkins said he “can readily see that [the book’s title] might give an inadequate impression of its contents” and in retrospect thinks he should have taken Tom Maschler ‘s advice and called the book The Immortal Gene.
In JulyThe Selfish Gene was listed as the most influential science book of all time in a poll to celebrate the 30th anniversary of the Royal Society science book prize. Dawkins builds upon George C. Williams ‘s book Adaptation and Natural Selectionwhich argued that altruism is not based upon group benefit per se but is a result of selection that occurs “at the level of the gene mediated by the phenotype ”  and any selection at the group level occurred only under rare circumstances.
Hamilton and others who opposed group selection and selection aimed directly at benefit to the individual organism: Despite the principle of ‘ survival of the fittest ‘ the ultimate criterion which determines whether [a gene] G will spread is not whether the behavior is to the benefit of the behaver, but whether it is to the benefit of the gene G With altruism this will happen only if the affected individual is a relative of the altruist, therefore having an increased chance of carrying the gene.
Dawkins begins by discussing the altruism that people display, indicating that he will argue it is explained by gene selfishness, and attacking group selection as an explanation.
El Gen Egoista / the Selfish Gene
He considers the origin of life with the arrival of molecules able to replicate themselves. From there, he looks at DNA ‘s role in evolutionand its organisation into chromosomes and geneswhich in his view behave selfishly. He describes organisms as apparently purposive but fundamentally simple survival machines, which use negative feedback to achieve control. This extends, he argues, to the brain ‘s ability to simulate the world with subjective consciousnessand signalling between species.
He then introduces the idea of the evolutionarily stable strategyand uses it to explain why alternative competitive strategies like bullying and retaliating exist. This allows him to consider what selfishness in a gene might actually mean, describing W. Hamilton ‘s argument for kin selectionthat genes for behaviour that improves the survival chances of close relatives can spread in a population, because those relatives carry the same genes.
Dawkins examines childbearing and raising children as evolutionary strategies. He attacks the idea of group selection for the good of the species as proposed by V. Wynne-Edwardsarguing instead that each parent necessarily behaves selfishly.
A question is whether parents should invest in their offspring equally or should favour some of them, and explains that what is best for the survival of the parents’ genes is not always best for individual children.
Similarly, Dawkins argues, there are conflicts of interest between males and females, but he notes that R. Fisher showed that the optimal sex ratio is In that case, the strategy of having a female offspring is safe, as she’ll have a pup, but the strategy of having a male can bring a large return dozens of pupseven though many males live out their lives as bachelors.
Amotz Zahavi ‘s theory of honest signalling explains stotting as a selfish act, he argues, improving the springbok’s chances of escaping from a predator by indicating how difficult the chase would be. Dawkins discusses why many species live in groups, achieving mutual benefits through mechanisms such as Hamilton’s selfish herd model: Altruism too can evolve, as in the social insects such as ants and bees, where workers give up the right to reproduce in favour of a sister, the queen; in their case, the unusual haplodiploid system of sex determination may have helped to bring this about, as females in a nest are exceptionally closely related.
The final chapter of the first edition introduced the idea of the memea culturally-transmitted entity such as a hummable tune, by analogy to genetic transmission. Dawkins describes God as an old idea which probably arose many times, and which has sufficient psychological appeal to survive effectively in the meme pool. The second edition added two more chapters. In describing genes as being “selfish”, Dawkins states unequivocally that he does not intend to imply that they are driven by any motives or willbut merely that their effects can be metaphorically and pedagogically described as if they were.
His contention is that the genes that are passed on are the ones whose evolutionary consequences serve their own implicit interest to continue the anthropomorphism in being replicated, not necessarily those of the organism. In later work, Dawkins brings evolutionary “selfishness” down to creation of a widely proliferated extended phenotype.
For some, the metaphor of “selfishness” is entirely clear, while to others it is confusing, misleading, or simply silly to ascribe mental attributes to something that is mindless. For example, Andrew Brown has written: Donald Symons also finds it inappropriate to use anthropomorphism in conveying scientific meaning in general, and particularly for the present instance.
He writes in The Evolution of Human Sexuality Dawkins proposes the idea of the “replicator”: The original replicator Dawkins’ R eplicator was the initial molecule which first managed to reproduce itself and thus gained an advantage over other molecules within the primordial soup. Dawkins writes that gene combinations which help an organism to survive and reproduce tend to also improve the gene’s own chances of being replicated, and, as a result, “successful” genes frequently provide a benefit to the organism.
An example of this might be a gene that protects the organism against a disease. This helps the gene spread, and also helps the organism.
El gen egoista / The Selfish Gene : Richard Dawkins :
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 behaviour, 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 example is the existence of segregation distorter genes that are detrimental to their host, but nonetheless propagate themselves at its expense. These unselected for but transmitted DNA variations connect the individual genetically dawkns its parents, but confer no survival benefit.
These examples might suggest that there is a power struggle between genes and their interactor. In fact, the claim is that there isn’t much of a struggle because the genes usually win without a fight. However, the claim is made that if the organism becomes intelligent enough to understand its own interests, as distinct from those of its genes, there can be true conflict. An example of such a conflict might be a person using birth control to prevent fertilisation, thereby inhibiting the replication of his or her genes.
But this action might not be a conflict of the ‘self-interest’ of the organism with his or her genes, since a person using birth control might also be enhancing the survival chances of their genes by limiting family size to conform with available resources, thus avoiding extinction as predicted under the Malthusian model of population growth. Dawkins says that his “purpose” in writing The Selfish Gene is “to examine the biology of selfishness and altruism.
However, as we shall see, there are special circumstances in which a gene can achieve its own selfish goals best by fostering a limited form of altruism at the level of individual animals. The claim is made that these “selfish” actions of genes lead to unselfish actions by organisms.
A dawkons upon this claim, supported by Dawkins in Chapter Although Dawkins and biologists in general recognize these phenomena result in more copies of a gene, evidence is inconclusive whether this success is selected for at a group or individual level.
In fact, Dawkins has proposed that it is at the level of the extended richafd Although Dawkins agrees that groups can assist survival, they rank as a “vehicle” for survival only if the group activity is replicated in descendants, recorded in the gene, the gene being the only true replicator.
An improvement in the survival lottery for the group must improve that for the gene for sufficient replication to occur. Dawkins argues qualitatively that the lottery for the gene is based upon a very long and broad record of events, and group advantages are usually too specific, too brief, and too fortuitous to change the gene lottery.
Prior to the s, it was common for altruism to be explained in terms of group selectionwhere the benefits to the organism or even population were supposed to account for the popularity of the genes responsible for the tendency towards that behaviour.
Modern versions of “multilevel selection” claim to have overcome the original objections,  namely, that at that time no known form of group selection led to an evolutionarily stable strategy.
The claim still is made by some that it would take only a single individual with a tendency towards more selfish behaviour to undermine a population otherwise filled only with the gene for altruism towards non-kin.
The Selfish Gene was extremely popular when first published, causing “a silent and almost immediate revolution in biology”,  and it continues to be widely read.
It has sold over a million copies, and has been translated into more than 25 languages. According to the ethologist Alan Grafenacceptance of adaptionist theories is hampered by a lack of a mathematical unifying theory and a belief that anything in words alone must be suspect.
One of the weaknesses of the sociological approach is that it tends only to seek confirmatory examples from among the huge diversity of animal behavior. Dawkins did not deviate from this tradition. As an example, see Thompson. The Selfish Gene further popularised sociobiology in Japan after its translation in With the addition of Dawkins’s book to the country’s consciousness, the term “meme” entered popular culture.
Inthe ecologist Arthur Cainone of Dawkins’s tutors at Oxford egoisya the s, called it a “young man’s book” which Dawkins points out was a deliberate quote of a commentator on egoisha New College, Oxford [a] philosopher A. Ayer ‘s Language, Truth, and Logic Dawkins noted that he had been “flattered by the comparison, [but] knew that Ayer had recanted much of his first book and [he] could hardly miss Cain’s pointed implication that [he] should, in the fullness of time, do the same.
As to the unit of selection: It is the gene, the unit of heredity. Dawkins’ later formulation is in his book The Extended Phenotypewhere the process of selection is taken to involve every possible phenotypical effect of a gene.
Stephen Jay Gould finds Dawkins’ position tries to have it both ways: The view of The Selfish Gene is that selection based upon groups and populations is rare compared to selection on individuals. Although supported by Dawkins and by many others, this claim continues to egoistx disputed. The conflict arises in part over defining concepts:. Wilson contends that although the selfish-gene approach was accepted “until [when] Martin Nowak, Corina Tarnita, and I demonstrated that inclusive fitness theory, often called kin selection theory, is both mathematically and biologically incorrect.
He egoksta earlier approaches to social evolution, saying: The proven best way dawkkins evolutionary biology, as in most of science, is to define a problem arising during empirical research, then select or devise the theory that is needed to solve it. Almost all research in inclusive-fitness theory has been the opposite: Experiments conducted over many years by social psychologists have revealed how swiftly and decisively people divide into groups, and then discriminate in favor of the one to which they belong.
Some authors consider facets of this debate between Dawkins and his critics about the level of selection to be blather: Other authors say Dawkins has failed to make some critical distinctions, in particular, the difference between group selection for group advantage and group selection conveying individual advantage.
A good deal of objection to The Selfish Gene stemmed from its failure to be always clear about “selection” and “replication”.
Dawkins says the gene is the fundamental unit of selection, and then points out that selection doesn’t act directly upon the gene, but upon ‘vehicles’ or ‘extended phenotypes’. Stephen Jay Gould geoista exception to calling the gene a ‘unit of selection’ because selection acted only upon phenotypes.
The word ’cause’ here is somewhat tricky: It certainly alters the likelihood of events, but a concatenation of contingencies decides what actually occurs.