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Why do some people get hot under the collar about the "selfish gene" model (SGM) of evolution? And why can't they discuss Richard Dawkins' arguments fairly? By Les Hearn |
SScientists like Steven Rose and Stephen Jay Gould accuse Dawkins of being a genetic determinist and holding to a reductionist philosophy. They also accuse him of being a human sociobiologist. Clive Bradley (WL59-60 and 62) has reported their criticisms at length, imputing political motives to Dawkins. I believe the criticisms do not stand up.
TThe most influential attacks on Dawkins' ideas have come from Steven Rose's book Lifelines or from Stephen Jay Gould.
PPhilosophical reductionism is the idea that you can explain fully the behaviour of a complex system, like a jumping frog, in terms of its physiology, its biochemistry, its chemistry, and finally in terms of its physics. Some forms of it have political connotations - crude genetic determinism which explains complex human social behaviours through "genes for" them, or neo-classical economics which presents economic structures as inevitable results of individuals' economic preferences.
FFor Rose a philosophical reductionist is someone who would seek to explain a frog's leap (his example) with the laws governing the quantum states of the electrons in the frog's molecules1. Rose insists that Dawkins is one of those. He is good enough to quote Dawkins' rebuttal: "I do not of course subscribe to this ridiculous belief... The belief attributed to 'reductionists' is exactly equivalent to the following: 'A bus drives fast, because the passengers sitting inside it are all fast runners.'"2. Dawkins' analogy is not a very good one and Rose gives a better one, saying that "reductionists wish to explain why the bus drives fast in terms of...the quantum properties of the atoms of which these molecules are composed". Strangely, he says that this ludicrous waste of time is "one perfectly appropriate way of describing how it is that the bus drives fast"2.
HHowever, most scientists are "reductionists" in a more limited methodological sense, as Rose himself points out3. He himself investigates the complex problem of memory in chicks through their tendency to peck at a coloured bead4. Is Dawkins one of these "limited" reductionists? He says he is. Is he one of the ultra-reductionists, going right down to the sub-atomic level (as Rose keeps emphasising)? There is no evidence whatever for this charge.
DDoes Dawkins's "selfish gene model" (SGM) say that organisation at gene level completely explains phenotype? I think not.
TThe SGM holds that individuals are vehicles for replicators, molecules that can copy themselves5. Evolution is possible because the copying is not perfect. Errors (mutations) occur, and some (rare exceptions, but enough to make a difference over long spans of time) enhance the gene's ability to replicate by enhancing the survival of the body it inhabits: to this extent it is "selfish".
BBut genes are like sentences made of three-letter words (codons), whose letters are chemical groups called nucleotides. Errors are usually the substitution of one nucleotide for another, changing the codon. Genes code for proteins and the mutated gene produces a protein which may be different, altering the fitness of the body. Rose's philosophical reductionist would be studying, not the genes, but the nucleotides and the atoms of which they are composed. Does Dawkins go down to the nucleotides? No, that would be "not helpful", "an absurdly reductionist reductio ad absurdum". He will not write a book called The Selfish Nucleotide6.
PPerhaps a partial philosophical reductionist would stick with the individual genes. Rose's reductionist methodology needs the "diversity that different levels of explanation offer"7. How about Dawkins? For him, the whole genome is important to the selfish gene: "Selection has favoured genes that co-operate with others"8, and "The manufacture of a body is a co-operative venture of such intricacy that it is almost impossible to disentangle the contribution of one gene from that of another"9. Does he ignore the individual, the vehicle? No: "Replicators are judged by their phenotypic effects"10, that is, by the effect they have on the nature and behaviour of the individual and its environment, the whole being termed "the extended phenotype". This is not even partly philosophical reductionism.
CClive repeats another of Gould's criticisms: "Evolution, he [Gould] notes, cannot operate on the level of genes, because genes are invisible in nature"11. To be fair, Gould does not say that evolution cannot operate on the level of genes - if he did, he would be rejecting Darwin's theory. He says that "selection [my emphasis] simply cannot see genes and pick among them directly. It must use bodies as an intermediary"12. Dawkins agrees: "Replicators are not, of course, selected directly but by proxy"10. Effectively, there is no difference between Gould and Dawkins. However crucial Clive thinks it is, "this dispute", according to Andrew Brown, "has now been resolved to the satisfaction of both sides". 13
CClive says "Dawkins' work is a general theoretical manifesto for genetic determinism in all its forms"11. So, is Dawkins a genetic determinist? True, he wrote the much-quoted "We are survival machines, robot vehicles blindly programmed to preserve the selfish molecules known as genes"11,14, and similar statements. Characteristically, he refuses to retract (while admitting "robot" was not the best word), though these exaggerated summary statements are contradicted by his detailed argumentation. Clive labours this point15: I think it is a poor and misleading analogy for Dawkins' ideas but why should Clive doubt Dawkins' explanation? 16 Slightly better is "they [genes] created us, body and mind"17. Curiously, even this was misquoted in Rose's book as "[they] control us, body and mind" (my emphasis) 18, making it sound extremely deterministic.
BBut all that is required of a "selfish" gene is that its vehicles should be more successful on average than vehicles carrying another allele: "Genes 'determine' behaviour only in a statistical sense"19. "The whole set of genes in a body constitutes a kind of genetic climate or background, modifying the effects of any particular gene"20. Chapter 2 of The Extended Phenotype is devoted to countering the charge of genetic determinism and Dawkins vehemently rejects the determinism of others. Giving the example of a child poor at maths, he says "any suggestion that [this] might have a genetic origin is likely to be greeted with something approaching despair: if it is in the genes...nothing can be done about it; you might as well give up attempting to teach the child mathematics. This is pernicious rubbish on an almost astrological scale. Genetic causes and environmental causes are in principle no different from each other... [and]... there is no general reason for expecting genetic influences to be any more irreversible than environmental ones"21.
LLastly, we have the question of (human) behaviour, which, Clive says, the SGM is "intended to explain"11. This is just not true.
CClive defeats this non-existent intention to his own satisfaction with the rhetorical question "how can the multifaceted aspects of human behaviour, from the production of art to the development of scientific knowledge, possibly be accounted for in this simple model?"11 But Dawkins never claimed that it could! As early as page three of The Selfish Gene he says "among animals, man is uniquely dominated by culture, by influences learned and handed down"22. In the Preface, Dawkins says "I am an ethologist and this is a book about animal behaviour"23; his "purpose is to examine the biology of altruism and selfishness" [my emphasis] 24 but his book is not "a descriptive account of the detailed behaviour of man".
IIn his reply - as in his original book - Dawkins rejects the simplistic equation, selfish gene = selfish behaviour4. Why can Clive not accept this? Rose does25 In looking at selfishness and altruism, Dawkins stands on the shoulders of G C Williams and others, who had previously shown how altruistic behaviour could evolve from selfish interests. They had already answered Clive's 'rhetorical' question, "where do generosity and selflessness come from?"15.
DDawkins says "if you wish...to build a society in which individuals co-operate generously and unselfishly towards a common good, you can expect little help from biological nature"22, but it is Clive who is the genetic determinist if he insists that efforts to create a social order of democratic cooperation need proof that our genes make us generous. Dawkins says "Let us try to teach generosity and altruism, because we are born selfish"22. Here, as elsewhere, Dawkins crudifies his own ideas - he himself shows how evolution can sometimes "select" for altruism - but don't we already know that teaching for altruism is a large part of bringing up and educating children? Clive accuses Dawkins of a "schizophrenic" view of human nature (casually insulting people with schizophrenia). Clive is "not content with a theory which would require of us a huge collective act of rebellious will against nature to achieve [our aim]"15. Aren't we, individually and collectively, rebelling against nature every day?
AApart from this, Dawkins steers clear of human sociobiology. No matter: he is condemned with the rest! Rose invents something called an "ultra-Darwinist", nominating Dawkins as the archetype. Ultra-Darwinists believe "that the unit of life, that which is the minimal life form, is an individual gene"26. Dawkins doesn't. Ultra-Darwinists also believe "Every observable aspect of the phenotype of an organism Ð its biochemistry, its form, its behaviour Ð is in some way adaptive"27. Dawkins does not believe this. Curiously, Rose quotes Dawkins contradicting this view but criticises him for not adhering to ultra-Darwinism strongly enough! 28
DDawkins and Edward O Wilson, author of Sociobiology, don't believe there are genes "for" everything, but you wouldn't know it from reading Lifelines. Rose claims that "Wilson argued that 'genes for homosexuality' could be preserved because they might make their bearers particularly supportive in the bringing up of children of their kin... and thus indirectly help perpetuate their own genes"29. In fact, the discussion in Sociobiology consists of Wilson describing the arguments of others, introducing these with the mild comment that "the influence of genetic factors towards the assumption of certain broad roles cannot be discounted"30. In the next sentence, Rose seems to question the integrity of Wilson, an extremely eminent scientist. "Wilson defends his [sic] hypothesis from any type of evidential refutation [my emphasis] by claiming that such genes, if they exist, 'are almost certainly incomplete in penetrance and variable in expressivity'"29.
LLet us compare Rose's partial quote with Wilson's complete sentence: "It remains to be said that if such genes really exist [my emphasis] they are almost certainly incomplete in penetrance and variable in expressivity, meaning that which bearers of the genes develop the behavioral trait and to what degree depend on the presence or absence of modifier genes and the influence of the environment"30. These are not the words of someone who believes in "genes for homosexuality", still less believes these would rigidly determine behaviour: they are the words of a scientist who retains an open mind. Wilson might well feel his views had been "traduced".
RRose gives a hostage to fortune with "There is of course [my emphasis] no empirical evidence for Wilson's [sic] propositions...Nor...is there any evidence that homosexual behaviour is widely displayed among non-human social animals as it should be if the argument of genetic advantage holds"29. Subsequently, Bruce Bagemihl published Biological Exuberance, summarising in over 700 pages just the evidence Rose requires "if the argument of genetic advantage holds". I am retaining an open mind.
CClive associates genes "for" homosexuality with Dawkins. When Dawkins corrects him16, we get Clive going "Hmm". Why can he not accept the fact that Dawkins has only ever mentioned genes for homosexuality for the sake of (someone else's) argument? 31.
DDawkins is not a genetic determinist or a philosophical reductionist. There is no evidence that he is motivated by right-wing views, and even if he were that would not automatically prove his views on evolution wrong. The SGM in no way seeks to explain human behaviour in its full complexity or even all animal behaviour. Dawkins explicitly states that the environment will always modify the effects of genes32.
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