Lewontin on Darwin

The current issue of The New York Review of Books features this essay, by Richard Lewontin. Officially it's a review of three recent books about Darwin and evolution. But since this is the NYRB we are discussing, the essay doesn't really say much about the books themselves.

The essay is disappointing, since for the most part I can't fathom Lewontin's point. Let's take a look:

Why do we call the modern theory of organic evolution “Darwinism”? Charles Darwin certainly did not invent the idea of evolution, that is, of the continuous change in time of the state of some system as a fundamental property of that system, or even the idea that a process of evolution had occurred in the history of life.

Lewontin never gives a clear answer to the question posed in the opening sentence above. He goes on to argue that none of the key components of Darwin's theory were original to him, which is certainly correct. Surely, though, the answer to the question is obvious. We call it Darwinism in honor of the person who changed evolution from a vague, largely discredited idea (in biology, at any rate) to a major topic of investigation.

It seems amazing that two naturalists could independently arrive at the same articulated theory of evolution from a consideration of the characteristics of some species of organisms in nature, their geographic distribution, and their similarities to other species. This amazement becomes considerably tempered, however, when one considers the social consciousness and economic milieu in which the theory arose, a milieu marked by the rise of competitive industrial capitalism in which individuals rose in the social hierarchy based, presumably, on their greater entrepreneurial fitness.

Amazement at the accomplishments of Darwin and Wallace is not tempered in the slightest by an understanding of the social milieu in which they worked. The connection between notions of fitness in economic competition and the idea that all modern organisms share a common ancestry mediated by natural forces is highly tenuous, to put it kindly. There was no shortage of other scientists operating in the same milieu, but they did not manage to revolutionize biology. Nowadays the staunchest critics of evolutionary science are also among the fiercest defenders of capitalism. Evidently the two do not necessarily go hand in hand.

While the nineteenth-century theory that some rose and some fell in society depending on their personal strengths and weaknesses is often referred to as “social Darwinism,” we would be much more in agreement with historical causation were we to call Darwinism “Biological Competitive Capitalism.” The perceived structure of the competitive economy provided the metaphors on which evolutionary theory was built.

I have the feeling Lewontin thinks he's saying something deep here, but I can't fathom what it is. That Darwin used some metaphors drawn from economics hardly reduces his theory to “Biological Competitive Capitalism.” (Is that as opposed to non-Competitive Capitalism?) I don't see what Darwin's social milieu has to do with his ideas relating embryology to common descent, or how an understanding of the artificial selection of pigeon breeds leads naturally to the idea of natural selection among species. We are all shaped by the social forces of our times, but it seems downright unkind to Darwin to suggest that his theory was just a straightforward application to nature of ideas prevalent in economics. Surely his near encyclopedic knowledge of the science of his time played a role as well.

One can hardly imagine anything that would have better justified the established social and economic theories of the Industrial Revolution than the claim that our very biological natures are examples of basic laws of political economy. How else are we to explain the immediate and continued commercial success of Darwin's books? The entire first edition of 1,250 copies of the Origin was immediately snapped up by booksellers. The expectation of public interest is revealed by the fact that a circulating library took five hundred copies.[3] The sixth edition, only thirteen years later, sold 11,000 copies. One cannot understand the origin and the immediate success of the Origin outside of the social and economic setting in which it was conceived, nor have historians of science ignored the question. The pages of the Journal of the History of Biology have certainly not been devoid of papers on the subject. Yet what we have been provided with in 2009 is biography and annotations on the Origin, Perhaps it is time for a socioeconomic analysis of our own preoccupations.

Where is the mystery in the success of Darwin's book? We're not exactly talking Stephen King numbers here, after all. Perhaps Darwin sold a lot of books because he was a talented writer who had a compelling story to tell on a topic of relevance to any thinking person. What more explantion is needed? Does Lewontin have any evidence that Darwin had commercial success because people were looking for scientific justification of the industrial revolution?

In the last few years J.K. Rowling has sold an insane number of books. Is this evidence of deep social forces at work? Can I not understand her success outside a deep understanding of modern economics.? Or did she just come up with a good yarn that appeals to a lot of different audiences?

Lewontin himself is well-known for his work in using gel electrophoresis to study the extent of genetic variation in populations and for his pioneering use of game theory in evolution. Can I not understand the genesis of Lewontin's work in these areas without also understanding his views on Marxism? Or was he just a smart guy who had some good ideas? I think Leowntin is creating mysteries where there aren't any.

Where he [Jerry Coyne] is less successful, as all other commentators have been, is in his insistence that the evidence for natural selection as the driving force of evolution is of the same inferential strength as the evidence that evolution has occurred. So, for example, he gives the game away by writing that when we examine a sequence of changes in the fossil record, we can

determine whether the sequences of changes at least conform to a step-by-step adaptive process. And in every case, we can find at least a feasible Darwinian explanation.

But to say that some example is not falsification of a theory because we can always “find” (invent) a feasible explanation says more about the flexibility of the theory and the ingenuity of its supporters than it says about physical nature.

I don't understand what it means to say that “natural selection is the driving force of evolution.” Given Lewontin's past writing (most notably his spandrels paper with Stephen Jay Gould) I would guess that his point is that some biologists are too quick to attribute some anatomical feature of some organism to the prolonged working of natural selection.

That may be true, but when we are talking about adaptations the evidence for natural selection seems to me to be very strong. For one thing, it is the only natural mechanism known that can account for complex structures (like bird wings or vertebrate blood clotting systems). For another, every complex structure studied to date shows clear evidence of being a cobbled together Rube Goldberg machine, which is exactly what we would expect if they were crafted by natural selection.

On top of this, biologists routinely use adaptive reasoning to generate testable hypotheses about the creatures they are studying. Lewontin would know better than I whether biologists engaging in flights of fancy is a genuine problem in the field, but it is undeniable that “the adaptationist program” has yielded great dividends over the years.

Jerry Coyne has responded to this point:

I have to say that Dick has indeed hit on a tricky issue in compiling the evidence for evolution. While natural selection is the only reasonable explanation for the evolution of adaptations, we cannot in most cases do more than adduce its plausibility. Direct demonstrations are rare (note to creationists: this is only because they're HARD TO DO, so don't take this out of context), and demonstrations in the past nearly impossible. And I should have talked more about this in WEIT (although we have discussed it on this website). But I can't help but sense Dick's own anti-selectionist views here: views that may stem from seeing others support preconceived biases by invoking soft adaptationism , and views that were of course instrumental in Lewontin and Gould's battle against sociobiology in the 1970s. When I was at Harvard with Dick and Steve, it was almost as though selection was a forbidden topic -- just once I would have liked either of them to have admitted openly, “Yes, of course selection is the only plausible explanation for adaptations.” In their fight against unthinking adaptationism, they nearly threw the baby out with the bathwater.

In fairness, I think Stephen Jay Gould was pretty clear on this point in several of his essays. I compiled some of his statements on the matter in this essay. But I share Coyne's frustration. I've never really understood what it is exactly that anti-selectionists are complaining about. If they agree that complex adapations arise as the result of gradual accretion mediated by natural selection, then I fail to see how they are really so different from people like Richard Dawkins or Daniel Dennett (two people often described as being benighted uber-selectionists). If they do not agree then I would like to hear their proposed alternative mechanism.

I wouldn't care so much but for the fact that the stridency of some anti-selectionist rhetoric (see Lynn Margulies, for example) gives ample fodder to the creationists.

At any rate, there is far more to Lewontin's essay than what I have responded to here, so go read the whole thing.