The Selfish Gene – Dawkins

Despite the poor rap that Dawkins has built over the years, this original work of his is a true classic. It is the foundation for much of the evolutionary science that came after it, and it really contains none of the ideas that may deter you from Dawkins these days.

I highly highly recommend it if you want to better understand evolution. The mental model that you have of evolution is probably not quite right, and could do with some refinement. This book will do exactly that.


  • We often think about our DNA as a carrier for our genes. But really we are the carrier for the DNA.
  • I like the mental model of “gene survival machines”. I think it does well to capture the role that genes have in all of this as well as the outcome of it all: “us”.
  • In a certain sense, you could say that Buddha was the first to realise the “survival machine” nature of human experience. Survival machines are motivated by desire (pleasure and pain), both of which in essence are the basis of suffering. Buddha realised that we live in these cycles of suffering (machine lives which are one loop in a cycle for a longer gene life), but also that we can escape the cycle of suffering through awareness and conscious living.
  • I imagine this is where the book is going to lead to, that consciousness was developed to serve the gene, but with the complexity of consciousness has arisen a new replicator; the idea (meme).
  • Ideas now serve the same purpose as DNA genes, in that they are replicatble (stored in neuron states of brains), longevity (they can last a whole carrier lifetime) and fecundity (ideas unlike genes have a near zero replication cost)
  • Reminds me of Sapians: Evolution is not the most efficient design across an eco-system (his example of trees) but rather the most “stable” to use the language here. Stable being the lease likely to disruption from internal random influence.
  • Thinking of systems in terms of “stable” or “unstable” is very useful.
  • I often refer back to the thing Trav said about why it’s worse to kill a human than a cow. His argument was that they look more similar to us and therefore we feel more for them and hence worse. But more likely is a gene perspective. Very rarely does any species kill its own kind compared to other species. This is because (similar to kin theory) other animals of the same species share more of our own DNA, and hence like our own compulsion to save ourselves and our children, we are more composed to save others of our species over other species. Genes that motivated the carrier to kill it's own species over other species would be unstable to a gene that didn't.
  • does it make sense to distinguish ourselves from viruses? Are we not just the cooperative effort of many “viruses” whose joint interest is the propagation of our sperm/eggs?
  • The idea of the extended phenotype seems to be that genes extend effects over the physical world which determine their ability to spread, regardless what “body” those effects surface in. Bodies are really just aggregates if extended effects.
  • If you ignore consciousness and just tried to model/explain the world and evolution. You would likely say that; genes are self replicating patterns, regardless of their form or container.
    • Over time, the genes that become most prevelent are the ones that were most successful in manipulating the physical world in to replicating their pattern (tautological)
    • You would say I that the “purpose” of these patterns is to reproduce themselves. Patterns that could “outsmart” competition would become more prevalent in the population.
    • Hence would continue to get more and more able at influencing the world.
  • However with this view the difference between individual selection and group selection seems surpurfluous.
    • Bodies are just aggregates of phenotype effects and synergetic replication methods.
    • Whether these happen strictly on the individual or group or external level doesn’t matter.
  • This is very Buddhist in nature. Everything is lacking in inherent existence. We are not a whole but a competing collection of phenotype effects.
    • Consciousness is a unifier of experience that makes us feel whole.
  • Embryonic reproduction as a means of propagation is better than continual growth because:
    • It can diversify more to improve more through natural selection
    • Multiple competing mutations is required for natural selection and will beat any single variation.
    • Trying to change all the cells of a fully formed vehicle is harder than just building a new one.
    • "saying how things have evolved. I am not saying how we humans morally ought to behave. I stress this, because I know I am in danger of being misunderstood by those people, all too numerous, who cannot distinguish a statement of belief in what is the case from an advocacy of what ought to be the case."
    • "This explanation is based on the misconception that I have already mentioned, that living creatures evolve to do things ‘for the good of the species’ or ‘for the good of the group’. It is easy to see how this idea got its start in biology. Much of an animal’s life is devoted to reproduction, and most of the acts of altruistic self-sacrifice that are observed in nature are performed by parents towards their young. ‘Perpetuation of the species’ is a common euphemism for reproduction, and it is undeniably a consequence of reproduction. It requires only a slight over-stretching of logic to deduce that the ‘function’ of reproduction is ‘to’ perpetuate the species. From this it is but a further short false step to conclude that animals will in general behave in such a way as to favour the perpetuation of the species. Altruism towards fellow members of the species seems to follow."
    • "To put it in a slightly more respectable way, a group, such as a species or a population within a species, whose individual members are prepared to sacrifice themselves for the welfare of the group, may be less likely to go extinct than a rival group whose individual members place their own selfish interests first. Therefore the world becomes populated mainly by groups consisting of self-sacrificing individuals. This is the theory of ‘group selection’, long assumed to be true by biologists not familiar with the details of evolutionary theory, brought out into the open in a famous book by V. C. Wynne-Edwards, and popularized by Robert Ardrey in The Social Contract. The orthodox alternative is normally called ‘individual selection’, although I personally prefer to speak of gene selection. The quick answer of the ‘individual selectionist’ to the argument just put might go something like this. Even in the group of altruists, there will almost certainly be a dissenting minority who refuse to make any sacrifice. If there is just one selfish rebel, prepared to exploit the altruism of the rest, then he, by definition, is more likely than they are to survive and have children. Each of these children will tend to inherit his selfish traits. After several generations of this natural selection, the ‘altruistic group’ will be over-run by selfish individuals, and will be indistinguishable from the selfish group. Even if we grant the improbable chance existence initially of pure altruistic groups without any rebels, it is very difficult to see what is to stop selfish individuals migrating in from neighbouring selfish groups, and, by inter-marriage, contaminating the purity of the altruistic groups."
    • "Perhaps one reason for the great appeal of the group selection theory is that it is thoroughly in tune with the moral and political ideals that most of us share. We may frequently behave selfishly as individuals, but in our more idealistic moments we honour and admire those who put the welfare of others first. We get a bit muddled over how widely we want to interpret the word ‘others’, though. Often altruism within a group goes with selfishness between groups. This is a basis of trade unionism. At another level the nation is a major beneficiary of our altruistic self-sacrifice, and young men are expected to die as individuals for the greater glory of their country as a whole. Moreover, they are encouraged to kill other individuals about whom nothing is known except that they belong to a different nation."
    • "The feeling that members of one’s own species deserve special moral consideration as compared with members of other species is old and deep. Killing people outside war is the most seriously-regarded crime ordinarily committed. The only thing more strongly forbidden by our culture is eating people (even if they are already dead). We enjoy eating members of other species, however. Many of us shrink from judicial execution of even the most horrible human criminals, while we cheerfully countenance the shooting without trial of fairly mild animal pests. Indeed we kill members of other harmless species as a means of recreation and amusement. A human foetus, with no more human feeling than an amoeba, enjoys a reverence and legal protection far in excess of those granted to an adult chimpanzee. Yet the chimp feels and thinks and—according to recent experimental evidence—may even be capable of learning a form of human language. The foetus belongs to our own species, and is instantly accorded special privileges and rights because of it. Whether the ethic of ‘speciesism’, to use Richard Ryder’s term, can be put on a logical footing any more sound than that of ‘racism’, I do not know. What I do know is that it has no proper basis in evolutionary biology."
    • "The muddle in human ethics over the level at which altruism is desirable—family, nation, race, species, or all living things—is mirrored by a parallel muddle in biology over the level at which altruism is to be expected according to the theory of evolution."
    • "The point that is relevant here is that, before the coming of life on earth, some rudimentary evolution of molecules could have occurred by ordinary processes of physics and chemistry. There is no need to think of design or purpose or directedness. If a group of atoms in the presence of energy falls into a stable pattern it will tend to stay that way. The earliest form of natural selection was simply a selection of stable forms and a rejection of unstable ones. There is no mystery about this. It had to happen by definition."
    • "Actually a molecule that makes copies of itself is not as difficult to imagine as it seems at first, and it only had to arise once. Think of the replicator as a mould or template. Imagine it as a large molecule consisting of a complex chain of various sorts of building block molecules. The small building blocks were abundantly available in the soup surrounding the replicator. Now suppose that each building block has an affinity for its own kind. Then whenever a building block from out in the soup lands up next to a part of the replicator for which it has an affinity, it will tend to stick there. The building blocks that attach themselves in this way will automatically be arranged in a sequence that mimics that of the replicator itself. It is easy then to think of them joining up to form a stable chain just as in the formation of the original replicator. This process could continue as a progressive stacking up, layer upon layer. This is how crystals are formed. On the other hand, the two chains might split apart, in which case we have two replicators, each of which can go on to make further copies."
    • "Evolutionary trends toward these three kinds of stability took place in the following sense: if you had sampled the soup at two different times, the later sample would have contained a higher proportion of varieties with high longevity/fecundity/copying-fidelity. This is essentially what a biologist means by evolution when he is speaking of living creatures, and the mechanism is the same—natural selection."
    • "The replicators that survived were the ones that built survival machines for themselves to live in. The first survival machines probably consisted of nothing more than a protective coat. But making a living got steadily harder as new rivals arose with better and more effective survival machines. Survival machines got bigger and more elaborate, and the process was cumulative and progressive."
    • "Four thousand million years on, what was to be the fate of the ancient replicators? They did not die out, for they are past masters of the survival arts. But do not look for them floating loose in the sea; they gave up that cavalier freedom long ago. Now they swarm in huge colonies, safe inside gigantic lumbering robots,* sealed off from the outside world, communicating with it by tortuous indirect routes, manipulating it by remote control. They are in you and in me; they created us, body and mind; and their preservation is the ultimate rationale for our existence. They have come a long way, those replicators. Now they go by the name of genes, and we are their survival machines."
    • "A body is the genes’ way of preserving the genes unaltered."
    • "If we wish, we can define a single gene as a sequence of nucleotide letters lying between a start and an end symbol, and coding for one protein chain. The word cistron has been used for a unit defined in this way, and some people use the word gene interchangeably with cistron. But crossing-over does not respect boundaries between cistrons. Splits may occur within cistrons as well as between them."
    • "The definition I want to use comes from G. C. Williams.* A gene is defined as any portion of chromosomal material that potentially lasts for enough generations to serve as a unit of natural selection."
    • "The fundamental principle involved is called negative feedback, of which there are various different forms. In general what happens is this. The ‘purpose machine’, the machine or thing that behaves as if it had a conscious purpose, is equipped with some kind of measuring device which measures the discrepancy between the current state of things, and the ‘desired’ state. It is built in such a way that the larger this discrepancy is, the harder the machine works. In this way the machine will automatically tend to reduce the discrepancy—this is why it is called negative feedback—and it may actually come to rest if the ‘desired’ state is reached."
    • "The Watt governor consists of a pair of balls which are whirled round by a steam engine. Each ball is on the end of a hinged arm. The faster the balls fly round, the more does centrifugal force push the arms towards a horizontal position, this tendency being resisted by gravity. The arms are connected to the steam valve feeding the engine, in such a way that the steam tends to be shut off when the arms approach the horizontal position. So, if the engine goes too fast, some of its steam will be shut off, and it will tend to slow down. If it slows down too much, more steam will automatically be fed to it by the valve, and it will speed up again."
    • "But the trouble with conspiracies, even those that are to everybody’s advantage in the long run, is that they are open to abuse. It is true that everybody does better in an all-dove group than he would in an ESS group. But unfortunately, in conspiracies of doves, a single hawk does so extremely well that nothing could stop the evolution of hawks. The conspiracy is therefore bound to be broken by treachery from within. An ESS is stable, not because it is particularly good for the individuals participating in it, but simply because it is immune to treachery from within."
    • "It is possible for humans to enter into pacts or conspiracies that are to every individual’s advantage, even if these are not stable in the ESS sense. But this is only possible because every individual uses his conscious foresight, and is able to see that it is in his own long-term interests to obey the rules of the pact. Even in human pacts there is a constant danger that individuals will stand to gain so much in the short term by breaking the pact that the temptation to do so will be overwhelming."
    • "But there are other ways in which the interests of individuals from different species conflict very sharply. For instance a lion wants to eat an antelope’s body, but the antelope has very different plans for its body. This is not normally regarded as competition for a resource, but logically it is hard to see why not. The resource in question is meat. The lion genes ‘want’ the meat as food for their survival machine. The antelope genes want the meat as working muscle and organs for their survival machine. These two uses for the meat are mutually incompatible; therefore there is conflict of interest."
    • "Superficially it looks as though the coach is selecting whole language groups as units. This is not what he is doing. He is selecting individual oarsmen for their apparent ability to win races. It so happens that the tendency for an individual to win races depends on which other individuals are present in the pool of candidates. Minority candidates are automatically penalized, not because they are bad rowers, but simply because they are minority candidates. Similarly, the fact that genes are selected for mutual compatibility does not necessarily mean we have to think of groups of genes as being selected as units, as they were in the case of the butterflies. Selection at the low level of the single gene can give the impression of selection at some higher level."
    • "The corresponding net benefit for the selfish behaviour was +18: it is a close-run thing, but the verdict is clear. I should give the food call; altruism on my part would in this case pay my selfish genes."
    • "We have probably all seen examples of the startling calculations that can be used to bring this home. For instance, the present population of Latin America is around 300 million, and already many of them are under-nourished. But if the population continued to increase at the present rate, it would take less than 500 years to reach the point where the people, packed in a standing position, formed a solid human carpet over the whole area of the continent. This is so, even if we assume them to be very skinny—a not unrealistic assumption. In 1,000 years from now they would be standing on each other’s shoulders more than a million deep. By 2,000 years, the mountain of people, travelling outwards at the speed of light, would have reached the edge of the known universe."
    • "But any altruistic system is inherently unstable, because it is open to abuse by selfish individuals, ready to exploit it."
    • "So we can think of two divergent sexual ‘strategies’ evolving. There was the large-investment or ‘honest’ strategy. This automatically opened the way for a small-investment exploitative strategy."
    • "There is no reason why a man should not inherit a tendency to develop a long penis from his mother."
    • "She stands to lose more if the child dies than the father does. More to the point, she would have to invest more than the father in the future in order to bring a new substitute child up to the same level of development. If she tried the tactic of leaving the father holding the baby, while she went off with another male, the father might, at relatively small cost to himself, retaliate by abandoning the baby too. Therefore, at least in the early stages of child development, if any abandoning is going to be done, it is likely to be the father who abandons the mother rather than the other way around."
    • "So, in mammals for example, it is the female who incubates the foetus in her own body, the female who makes the milk to suckle it when it is born, the female who bears the brunt of the load of bringing it up and protecting it. The female sex is exploited, and the fundamental evolutionary basis for the exploitation is the fact that eggs are larger than sperms."
    • "By this I simply mean that there will be a tendency for genes that say ‘Body, if you are male leave your mate a little bit earlier than my rival allele would have you do, and look for another female’, to be successful in the gene pool."
    • "Courtship feeding by the male probably represents direct investment by him in the eggs themselves. It therefore has the effect of reducing the disparity between the two parents in their initial investment in the young."
    • "Excess copulations may not actually cost a female much, other than a little lost time and energy, but they do not do her positive good. A male on the other hand can never get enough copulations with as many different females as possible: the word excess has no meaning for a male."
    • "Most of what is unusual about man can be summed up in one word: ‘culture’. I use the word not in its snobbish sense, but as a scientist uses it. Cultural transmission is analogous to genetic transmission in that, although basically conservative, it can give rise to a form of evolution."
    • "This is that when we look at the evolution of cultural traits and at their survival value, we must be clear whose survival we are talking about. Biologists, as we have seen, are accustomed to looking for advantages at the gene level (or the individual, the group, or the species level according to taste). What we have not previously considered is that a cultural trait may have evolved in the way that it has, simply because it is advantageous to itself."
    • "A simple replicator, whether gene or meme, cannot be expected to forgo short-term selfish advantage even if it would really pay it, in the long term, to do so. We saw this in the chapter on aggression. Even though a ‘conspiracy of doves’ would be better for every single individual than the evolutionarily stable strategy, natural selection is bound to favour the ESS."
    • "reciprocal altruism’."
    • "What matters, for the game to qualify as a true Prisoner’s Dilemma, is their rank order. The temptation to defect must be better than the reward for mutual cooperation, which must be better than the punishment for mutual defection, which must be better than the sucker’s pay-off. (Strictly speaking, there is one further condition for the game to qualify as a true Prisoner’s Dilemma: the average of the temptation and the sucker pay-offs must not exceed the reward. The reason for this additional condition will emerge later.)"
    • "The more you think about it, the more you realize that life is riddled with Iterated Prisoner’s Dilemma games,"
    • "It is possible to be even more forgiving than Tit for Tat. Tit for Two Tats allows its opponents two defections in a row before it eventually retaliates. This might seem excessively saintly and magnanimous. Nevertheless Axelrod worked out that, if only somebody had submitted Tit for Two Tats, it would have won the tournament. This is because it is so good at avoiding runs of mutual recrimination."
    • "It just so happened that in Axelrod’s original tournament about half the entries were nice. Tit for Tat won in this climate, and Tit for Two Tats would have won in this climate if it had been submitted. But suppose that nearly all the entries had just happened to be nasty. This could very easily have occurred. After all, 6 out of the 14 strategies submitted were nasty. If 13 of them had been nasty, Tit for Tat wouldn’t have won. The ‘climate’ would have been wrong for it. Not only the money won, but the rank order of success among strategies depends upon which strategies happen to have been submitted; depends, in other words, upon something as arbitrary as human whim."
    • "The mathematician’s simple distinction between the one-off Prisoner’s Dilemma game and the Iterated Prisoner’s Dilemma game is too simple. Each player can be expected to behave as if he possessed a continuously updated estimate of how long the game is likely to go on. The longer his estimate, the more he will play according to the mathematician’s expectations for the true iterated game: in other words, the nicer, more forgiving, less envious he will be. The shorter his estimate of the future of the game, the more he will be inclined to play according to the mathematician’s expectations for the one-off game: the nastier, and less forgiving will he be."
    • "The Extended Phenotype, the book that, more than anything else I have achieved in my professional life, is my pride and joy."
    • "Some biologists go so far as to see DNA as a device used by organisms to reproduce themselves, just as an eye is a device used by organisms to see! Readers of this book will recognize that this attitude is an error of great profundity."
    • "Look at what can happen when parasite genes and host genes do share a common exit. Wood-boring ambrosia beetles (of the species Xyleborus ferrugineus) are parasitized by bacteria that not only live in their host’s body but also use the host’s eggs as their transport into a new host. The genes of such parasites therefore stand to gain from almost exactly the same future circumstances as the genes of their host. The two sets of genes can be expected to ‘pull together’ for just the same reasons as all the genes of one individual organism normally pull together. It is irrelevant that some of them happen to be ‘beetle genes’, while others happen to be ‘bacterial genes’. Both sets of genes are ‘interested’ in beetle survival and the propagation of beetle eggs, because both ‘see’ beetle eggs as their passport to the future. So the bacterial genes share a common destiny with their host’s genes, and in my interpretation we should expect the bacteria to cooperate with their beetles in all aspects of life."
    • "When we have a cold or a cough, we normally think of the symptoms as annoying byproducts of the virus’s activities. But in some cases it seems more probable that they are deliberately engineered by the virus to help it to travel from one host to another. Not content with simply being breathed into the atmosphere, the virus makes us sneeze or cough explosively. The rabies virus is transmitted in saliva when one animal bites another. In dogs, one of the symptoms of the disease is that normally peaceful and friendly animals become ferocious biters, foaming at the mouth."
    • "The point of comparing rebel human DNA with invading parasitic viruses is that there really isn’t any important difference between them. Viruses may well, indeed, have originated as collections of breakaway genes. If we want to erect any distinction, it should be between genes that pass from body to body via the orthodox route of sperms or eggs, and genes that pass from body to body via unorthodox, ‘sideways’ routes."
    • "all ‘own’ chromosomal genes should be regarded as mutually parasitic on one another."
    • "‘The rabbit runs faster than the fox, because the rabbit is running for his life while the fox is only running for his dinner.’"
    • "Natural selection favours those genes that manipulate the world to ensure their own propagation."
    • "Vehicles don’t replicate themselves; they work to propagate their replicators."
    • "The fundamental unit, the prime mover of all life, is the replicator. A replicator is anything in the universe of which copies are made. Replicators come into existence, in the first place, by chance, by the random jostling of smaller particles."
    • "I now like to express the essential idea of an ESS in the following more economical way. An ESS is a strategy that does well against copies of itself. The rationale for this is as follows. A successful strategy is one that dominates the population. Therefore it will tend to encounter copies of itself. Therefore it won’t stay successful unless it does well against copies of itself. This definition is not so mathematically precise as Maynard Smith’s, and it cannot replace his definition because it is actually incomplete. But it does have the virtue of encapsulating, intuitively, the basic ESS idea."



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