Shelves: science , non-fiction , bloody-brilliant , life-changing Although I consider myself a Jesus-loving, god-fearing, creationist, I simply LOVE reading about evolution. And Dawkins is nothing if not lucid and accessible. He presents the topic and various questions and scientific controversies in a way that anybody with a willingness to pay attention can follow it. Some of the chapters were a bit more of a slog as Dawkins has to resort to Although I consider myself a Jesus-loving, god-fearing, creationist, I simply LOVE reading about evolution. Some of the chapters were a bit more of a slog as Dawkins has to resort to scary scary math and numbers to prove some of his points and set up for even more mindblowing stuff in future chapters. But most of the time, this book is chock full of insanely interesting examples and user-friendly analogies.
|Published (Last):||13 September 2008|
|PDF File Size:||5.62 Mb|
|ePub File Size:||15.89 Mb|
|Price:||Free* [*Free Regsitration Required]|
Background[ edit ] Dawkins builds upon George C. 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.
Hamilton, The Evolution of Altruistic Behavior, pp. He considers the origin of life with the arrival of molecules able to replicate themselves. He describes organisms as apparently purposive but fundamentally simple survival machines, which use negative feedback to achieve control. He then introduces the idea of the evolutionarily stable strategy , and 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. 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-Edwards , arguing instead that each parent necessarily behaves selfishly. 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 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 meme , a 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. 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. 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.
He writes in The Evolution of Human Sexuality :  "In summary, the rhetoric of The Selfish Gene exactly reverses the real situation: through [the use of] metaphor genes are endowed with properties only sentient beings can possess, such as selfishness, while sentient beings are stripped of these properties and called machines The anthropomorphism of genes The fundamental units of natural selection, the basic things that survive or fail to survive, that form lineages of identical copies with occasional random mutations, are called replicators.
DNA molecules are replicators. 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. 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 to its parents, but confer no survival benefit. 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.
Altruism[ edit ] 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.
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. We agree that the group selection controversy ought to be a controversy about groups as vehicles, and we could easily agree to differ on the answer I coined the [term] vehicle not to praise it but to bury it Darwinism can work on replicators whose phenotypic effects interactors are too diffuse, too multi-levelled, too incoherent to deserve the accolade of vehicle Extended phenotypes can include inanimate artifacts like beaver dams But the vehicle is not something fundamental 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. As it happens the outcome, in my view, is a decisive victory for the individual organism. The group is too wishy-washy an entity. 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.
It has sold over a million copies, and has been translated into more than 25 languages. According to the ethologist Alan Grafen , acceptance 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. In later writings Dawkins goes even further and argues that phenotypic traits are what really matter in selection and that they can be treated independently of their being organized into vehicles Dawkins is far from a genetic determinist, but he is certainly a genetic reductionist.
It is the gene, the unit of heredity. The important differences between genes emerge only in their effects. The technical word phenotype is used for the bodily manifestation of a gene, the effect that a gene has on the body Natural selection favours some genes rather than others not because of the nature of the genes themselves, but because of their consequences—their phenotypic effects But we shall now see that the phenotypic effects of a gene need to be thought of as all the effects that it has on the world.
The phenotypic effects of a gene are the tools by which it levers itself into the next generation. All I am going to add is that the tools may reach outside the individual body wall Examples that spring to mind are artefacts like beaver dams, bird nests, and caddis houses. Although supported by Dawkins and by many others, this claim continues to be disputed. The conflict arises in part over defining concepts: "Cultural evolutionary theory, however, has suffered from an overemphasis on the experiences and behaviors of individuals at the expense of acknowledging complex group organization Many important behaviors related to the success and function of human societies are only properly defined at the level of groups".
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 criticises earlier approaches to social evolution, saying: " The proven best way in 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: hypothesize the key roles of kinship and kin selection, then look for evidence to test that hypothesis. 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.
Gould, p. It certainly alters the likelihood of events, but a concatenation of contingencies decides what actually occurs. Dawkins thinks the use of "cause" as a statistical weighting is acceptable in common usage. There are no genes for interactions, as such: rather, each unique set of inherited genes contributes interactively to one unique phenotype Darwin, p. The distinction is as follows:   replicator: an entity that passes on its structure largely intact in successive replications.
Hull suggests that, despite some similarities, Dawkins takes too narrow a view of these terms, engendering some of the objections to his views. According to Godfrey-Smith, this more careful vocabulary has cleared up "misunderstandings in the "units of selection" debates. From that point on behavioral formation is a problem of constant interplay between genetic potential and environmental shaping"  —D.
Thiessen, Mechanism specific approaches in behavior genetics, p. Gene activation depends upon the cellular milieu. Thompson quotes Sarkar:  "there is no clear technical notion of "information" in molecular biology.
It is little more than a metaphor that masquerades as a theoretical concept and Thompson goes on to suggest that the cell-environment interrelationship has much to do with reproduction and inheritance, and a focus on the gene as a form of "information [that] passes through bodies and affects them, but is not affected by them on its way through"  is tantamount to adoption of a form of material-informational dualism that has no explanatory value and no scientific basis.
Thomson, p. Moral arguments[ edit ] Another criticism of the book is its treatment of morality, and more particularly altruism, as existing only as a form of selfishness: "It is important to realize that the above definitions of altruism and selfishness are behavioural, not subjective. I am not concerned here with the psychology of motives My definition is concerned only with whether the effect of an act is to lower or raise the survival prospects of the presumed altruist and the survival prospects of the presumed beneficiary.
This edition added two extra chapters, and substantial endnotes to the preceding chapters, reflecting new findings and thoughts. It also added a second preface by the author, but the original foreword by Trivers was dropped. The book contains no illustrations. The book has been translated into at least 23 languages including Arabic, Thai and Turkish.
“O Gene Egoísta” é eleito o livro científico mais influente de todos os tempos
O Gene Egoísta