That’s the blurb on the back cover of my copy of The Selfish Gene, a 30th anniversary edition, with a new introduction and expanded endnotes by the author.
I wish I could say I enjoyed it as much as whoever wrote that did.
My frustration with the text comes from two main sources.
First, the very metaphor Dawkins has chosen to communicate his conceptual framework--that of an anthropomorphic, “selfish” gene, working willfully to perpetuate itself in subsequent generations of the organisms that it inhabits--does, for me, exactly the opposite of what Dawkins evidently wants it to. He expects the metaphor to make natural selection easier to understand. For me, however, it obscures the essential truth of natural selection under an unnecessary and inexact metaphor.
Second, both Richard Dawkinses--the one who wrote The Selfish Gene in 1976, and especially the one who wrote the new introduction and expanded endnotes in 2006, comes across as, to put it bluntly, an arrogant jerk.
The endnotes, especially, read very much like a petulant tirade against Dawkins’s many critics. And in that tirade, it seems, the esteemed professor isn’t above taking his share of pot shots.
One critic complained that my argument was ‘philosophical’, as though that was sufficient condemnation. Philosophical or not, the fact is that neither he nor anybody else has found any flaw in what I said. And ‘in principle’ arguments such as mine, far from being irrelevant to the real world, can be more powerful than arguments based on particular factual research. My reasoning, if it is correct, tells us something important about life everywhere in the universe. Laboratory and field research can tell us only about life as we have sampled it here.
That, from my perspective, is Dawkins’s erudite way of saying that he doesn’t expect other scientists to understand the power of his intellect, myopically focused, as they inevitably are, on the simple facts of their laboratory and field research. It was a bit of a surprise to encounter these comments, as I typically enjoy reading endnotes to get a kind of etymology and color commentary on the concepts and quotations expressed in a book, not to be reminded over and over again that the author thinks he’s smarter than everybody else.
And, to further prove his point, Dawkins includes after the endnotes a handful of extracts from reviews of his work--each more fawning than the one before.
The author’s modest assessment of his own ideas tends to disarm criticism, and here and there the reader finds himself flattered by the suggestion that he should work out a better model if he doesn’t like the one given.
It makes me wonder if I even read the same book that these reviewers did. Dawkins, in my view, wasn’t flattering me by assuming I could come up with a better idea than he had, he was smugly and passive-aggressively asserting that he knew that I couldn’t.
But let me get back to my first frustration, because it is by far my bigger problem with the text. Based on the extended defense of the metaphor Dawkins offers in his new introduction, I have to assume I’m not the only person who was frustrated with the device.
The Selfish Gene has been criticized for anthropomorphic personification and this too needs an explanation, if not an apology. I employ two levels of personification: of genes, and of organisms. Personification of genes really ought not to be a problem, because no sane person thinks DNA molecules have conscious personalities, and no sensible reader would impute such a delusion to an author.
More passive-aggressive chicanery. “No sane person” and “no sensible reader” are nice ways to call one’s critics insane and insensible. But I don’t object to his personification of genes because I think he’s saying genes actually do have personalities. Dawkins goes to great lengths here and elsewhere to disarm his readers of that interpretation.
I once had the honour of hearing the great molecular biologist Jacques Monod talking about creativity in science. I have forgotten his exact words, but he said approximately that, when trying to think through a chemical problem, he would ask himself what he would do if he were an electron. Peter Atkins, in his wonderful book Creation Revisited, uses a similar personification when considering the refraction of a light beam, passing into a medium of higher refractive index which slows it down.
And a paragraph or so down…
Personification of this kind is not just a quaint didactic device. It can also help a professional scientist to get the right answer, in the face of tricky temptations to error. Such is the case with Darwinian calculations of altruism and selfishness, cooperation and spite. It is very easy to get the wrong answer. Personifying genes, if done with due care and caution, often turns out to be the shortest route to rescuing a Darwinian theorist drowning in muddle. While trying to exercise that caution, I was encouraged by the masterful precedent of W. D. Hamilton, one of four named heroes of the book. In a paper of 1972 (the year in which I began to write The Selfish Gene) Hamilton wrote:
“A gene is being favoured in natural selection if the aggregate of its replica forms an increasing fraction of the total gene pool. We are going to be concerned with genes supposed to affect the social behaviour of their bearers, so let us try to make the argument more vivid by attributing to the genes, temporarily, intelligence and a certain freedom of choice. Imagine that a gene is considering the problem of increasing the number of its replicas, and imagine that it can choose between…”
That is exactly the right spirit in which to read much of The Selfish Gene.
That’s all fine. But what I object to is that the personification doesn’t help me get to the right answer. Actually, it gets in the way of my understanding how genes actually work.
The key concept, to my way of thinking, is not the gene, but selection.
Within each species some individuals leave more surviving offspring than others, so that the inheritable traits (genes) of the reproductively successful become more numerous in the next generation. This is natural selection: the non-random differential reproduction of genes. Natural selection has built us, and it is natural selection we must understand if we are to comprehend our own identities.
That’s from the foreword to the original edition of this book, and I agree with it wholeheartedly. The focus should be on the process of selection, and the thing being selected. Personifying genes puts the emphasis in the wrong place, because it isn’t the gene that’s naturally selected, it’s the gene’s expressed biological structure or behavior. Dawkins, and other evolutionary biologists, call that the gene’s phenotype, and Dawkins himself will go on to write a book even more groundbreaking than The Selfish Gene about the importance of the phenotype in natural selection. In The Extended Phenotype he will argue, correctly, I think, that it’s not just the biological structures and behaviors of the organism that get selected, but also the effects those structures and behaviors have on the external environment. These “extended” phenotypes, the beaver’s dam perhaps serving as the most famous example, are just as important to determining which genes occupy the gene pool as the things the genes are more directly responsible for.
Understanding the role of the phenotype, extended or otherwise, in natural selection, is absolutely key to understanding evolution, and personifying the gene, I think, obscures that fact.
Dawkins, of course, knows the importance of the phenotype.
Once upon a time, natural selection consisted of the differential survival of replicators floating free in the primeval soup. Now, natural selection favors replicators that are good at building survival machines, genes that are skilled in the art of controlling embryonic development.
This is absolutely essential. Selection at the organism level (what Dawkins here calls a “survival machine”), drives survival at the gene level. That means that genes that express things that aren’t selected for, or which are selected against, don’t survive. And it also means that genes that don’t express anything, or express things that cannot be selected, survive or perish for entirely different reasons. It has nothing to do with the “selfishness” of the gene.
But even knowing this, Dawkins allows his language to get sloppy.
We saw that some people regard the species as the unit of natural selection, others the population or group within the species, and yet others the individual. I said that I preferred to think of the gene as the fundamental unit of natural selection, and therefore the fundamental unit of self-interest.
And there he goes, ready to jump off into his gene personification strategy, apparently blind to the obfuscation of what’s really going on that results. It all gets quickly complicated, but throughout his many examples and applications of the metaphor, I can’t shake the feeling that Dawkins has devolved into “just-so” story territory with some of his conclusions.
Other evolutionary biologists I’ve read tend to think that everything is driven by gene expression and natural selection. Not just biological structures, but behaviors as well. Interestingly, Dawkins seems determined to carve out a special territory in animal behavior that genes do not affect. But it is here that his personification of genes really seemed to break down for me.
He talks, reasonably, about how difficult it would be for genes to predict and prepare the animal they live in for all the dangers it will face in its life.
When an embryo survival machine is being built, the dangers and problems of its life lie in the future. Who can say what carnivores crouch waiting for it behind what bushes, or what fleet-footed prey will dart and zig-zag across its path? No human prophet, nor any gene. But some general predictions can be made. Polar bear genes can safely predict that the future of their unborn survival machine is going to be a cold one. They do not think of it as a prophecy, they do not think at all: they just build in a thick coat of hair, because that is what they have always done before in previous bodies, and that is why they still exist in the gene pool.
See how excellently Dawkins destroys his own personification metaphor with this last explanatory sentence? It practically made me call out: “If they don’t do any thinking, then why are you bothering to tell me that they do? What’s wrong with the explanation in your last sentence?” Polar bear genes code for thick coats of hair because evolution has selected polar bears with thick coats of hair as better adapted to their environment, and they have therefore produced more offspring than ancient polar bears without thick coats of hair. Dawkins makes the exact same point as the paragraph continues, but nestled comfortably back inside his metaphor.
They also predict that the ground is going to be snowy, and their prediction takes the form of making the coat of hair white and therefore camouflaged. If the climate of the Arctic changed so rapidly that the baby bear found itself born into a tropical desert, the predictions of the genes would be wrong, and they would pay the penalty. The young bear would die, and they inside it.
No, the genes aren’t making any predictions, right or wrong. Thick coats of hair would not have a selective advantage in a tropical climate, so animals with those genes would no longer reproduce more frequently than others, and the presence of those genes in the gene pool would be reduced. Is that really so hard to understand?
But let me allow Dawkins to build to his bigger idea--that genes actually don’t control all animal behavior. His claim is that in order to best ensure their survival, genes can only provide their “survival machines” with a simple set of instructions, what Dawkins calls a “program,” that will work more often than not.
One way for genes to solve the problem of making predictions in rather unpredictable environments is to build in a capacity for learning. Here the program may take the form of the following instructions to the survival machine: ‘Here is a list of things defined as rewarding: sweet taste in the mouth, orgasm, mild temperature, smiling child. And here is a list of nasty things: various sorts of pain, nausea, empty stomach, screaming child. If you should happen to do something that is followed by one of the nasty things, don’t do it again, but on the other hand repeat anything that is followed by one of the nice things.’
Other than the amusing idea that Dawkins has actually written the program for the human mind here, it again strikes me as needlessly complicated and overwrought. There is no program, so why describe it as such? Genes that code for pleasurable sensations from certain stimuli (if such genes truly exist) are endemic to certain species because their phenotypes (a desire for sweet tasting things) were selected as advantageous to survival and reproduction. Searching for sweet tasting food resulted finding more nutritious food, which resulted in stronger “survival machines.”
But okay, if it’s easier for you to think that the genes are consciously programming their hosts to manipulate their environment in certain ways, then go ahead and think that way. That metaphor is, essentially, why Dawkins wrote this book. The book is more about a way of understanding evolution than it is about understanding evolution itself.
Here’s Dawkins’s final conclusion associated with this line of thinking.
I am trying to build up the idea that animal behaviour, altruistic or selfish, is under the control of genes in only an indirect, but still very powerful, sense. By dictating the way survival machines and their nervous systems are built, genes exert ultimate power over behaviour. But the moment-to-moment decisions about what to do next are taken by the nervous system. Genes are the primary policy-makers; brains are the executives. But as brains become more highly developed, they took over more and more of the actual policy decisions, using tricks like learning and simulation in doing so. The logical conclusion to this trend, not yet reached in any species, would be for the genes to give the survival machine a single overall policy instruction: do whatever you think best to keep us alive.
So, in this world, where genes provide high-level instructions, and brains make day-to-day decisions, does that mean some behaviors aren’t caused by genes? I can’t tell because Dawkins seems to take both sides of the argument in the excerpt above--genes exert both indirect influence and ultimate power over behavior. And if there are behaviors that are not caused by genes, can those behaviors still be naturally selected? Whatever their source, gene expression or brain decision-making, will certain behaviors best adapted to their environment come to dominate a population through an evolutionary process? And if so, if “brain” behaviors are naturally selected, does that close the door on the little piece of free will that might otherwise be poking through Dawkins’s theory? Despite not being caused by our selfish genes, our behaviors have still been selected for us by Darwinian evolution, leaving us incapable of even contemplating non-selected course of actions.
I don’t know the answers to any of these questions. And Dawkins certainly doesn’t provide them for me. In fact, he barely even acknowledges that these questions exist. Much of The Selfish Gene was like that for me--the application of the “selfish” metaphor placing far more questions in my mind than answers.
But hold on. Before I try to dissect even more confusing examples, perhaps it’s best simply to end on two surprising confessions I came across in the text.
Is there any experimental evidence for the genetic inheritance of altruistic behaviour? No, but that is hardly surprising, since little work has been done on the genetics of any behaviour.
And…
This story illustrates a number of important points which came up in the previous chapter. It shows that it can be perfectly proper to speak of a ‘gene for behaviour so-and-so’ even if we haven’t the faintest idea of the chemical chain of embryonic causes leading from gene to behaviour.
Wait...what? You wrote a whole book about selfish genes, dedicating more than half of it to how those selfish genes drive certain behaviors (altruism being the current behavior-du-jour, evidently, among evolutionary biologists), and not only is there no evidence that genes do that, but you also don’t have the faintest idea how they might do that?
I forget which scientist said that if you don’t know how something works, then you don’t really know that it does work. I’d like to think that that scientist was Richard Dawkins, who has probably at least thought of using that argument in his battles with Creationists.
I give up.
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This post first appeared on Eric Lanke's blog, an association executive and author. You can follow him on Twitter @ericlanke or contact him at eric.lanke@gmail.com.
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