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There is no revolution in genetics

400px-Dawkins_at_UT_Austin
Credit: Shane Pope

The always fascinating Aeon Magazine has a very interesting piece up by my friend David Dobbs, Die, selfish gene, die. As you can tell it is something of a broadside against Richard Dawkins’ ideas promoted in The Selfish Gene. The subheading is straightforward: “The selfish gene is one of the most successful science metaphors ever invented. Unfortunately, it’s wrong.” As I stated on Twitter the writing here was splendid, but at the end of the day I must disagree with the conclusions on the balance. It is true that the selfish gene is wrong as a metaphor and model, but  all representations of this sort have an element of stylized artifice which does not stand up to scrutiny. John Dalton’s atomic theory is also wrong, but still highly useful in imparting conceptual truth. But across 5,000 words David surveys the landscape and seems to come away with the lesson that evolutionary biology took a wrong turn at some point, and that the calcified old order is now facing a revolt from below. To me this does not seem like an accurate representation of what I know, though to be fair sometimes it was difficult for me to gauge whether David himself is always of one mind on the issue. The piece is wide ranging and expansive, and has so much detail that it is difficult to start at one particular place.

Naturally I have some technical and scientific gripes which may be irrelevant to most readers. As I observed on Twitter the mention of microarrays as a means to understand gene expression makes me wonder if this piece was written in 2005, as the field has moved to RNA-Seq. David admitted that this article was years in the making, so this peculiarity is easily explained then. But there is another section where he characterizes William D. Hamilton as a statistician. I think this misleads somewhat as to the primary thrust of his career. To my knowledge Hamilton’s forte was not detailed analysis of reams of data, extracting patterns from the noise. Rather, he engaged in modeling, extrapolating from the core truths of Mendelian genetics.

But the above are minor gripes, and more matters of style than substance. There are some issues where I think the piece may be substantively incorrect. Going in order of my concern, first David seems to imply that the genius of genetics in relation to Charles Darwin’s theory of natural selection is that it presented a straightforward mechanism by which one could introduce variation through mutation. This seems wrong to me. Rather, the power of genetics in a Mendelian framework is that it is a discrete manner of transmission where variation does not decay every generation. Natural selection needs variation to operate, and previous “blending models” of inheritance were subject to the problem that variation decays very rapidly in this framework. Second, the piece contends that the modern evolutionary synthesis was “all about the maths.” A formal mathematical framework was probably a necessary condition for the synthesis as we understand it, but it seems too much to say that this was overwhelmingly dominant. Two of the major figures in the synthesis, Theodosius Dobzhansky and Ernst Mayr, were definitely not mathematical. Dobzhansky saw particular empirical results, and leaned upon Sewall Wright’s formal models to support them, but he admitted that the mathematics escaped him. Mayr famously inveighed against mathematical genetics in his later years.

Then there’s the description of the origin and development of the theory of inclusive fitness. This just seems totally wrong to me (unless it is simply not clear). Though both R. A. Fisher and J. B. S. Haldane alluded to the broader logic of inclusive fitness at various points, the mathematical framework was developed by William D. Hamilton, John Maynard Smith, and George Price in the 1960s. More precisely, two papers in 1964 by Hamilton titled The Genetical Evolution of Social Behaviour laid the groundwork for the formal exploration of the problem of altruism. If I had read the piece without that knowledge I’d have thought it had been developed decades earlier.

Reading through the article I could almost see areas that I felt had to be edited out, or rewritten to be comprehensible to the broader public. I admire David’s effort and doubt I could have pulled something similar off. This is not an easy topic to tackle, the conceptual and empirical landscape is a minefield for someone to explore. Too many of the scientific assertions in the detail I’m not sure I can respond to, because I’m not totally clear on what’s being said, or implied. Many complex ideas and positions are condensed down to a sentence or two, to the point where they become obscure to me.

But there are a few points I’d like to enter into the record. First, as noted by many ideas like genetic assimilation have been around for a long time. C. H. Waddington is not an obscure figure. Evolutionary genetics has not been in stasis since the modern synthesis, or even the 1970s. Genomics means that there is a surfeit of data, and different theories are going to be useful in explaining particular aspects of the shape of biological variation. The emergence of evo-devo in the 2000s was certainly interesting, though I don’t think it “changed everything,” as some are fond of declaring. The narrative that the modern synthesis is being “overthrown” seems to be a persistent one, and always seems t finds support from the latest hot area of study. In the 1970s it was the molecular theory of neutral evolution, which rebutted excessive adaptationism, in the 2000s it was evo-devo, and now it is epigenetics. Science is not like religion, and heretical sects do not just explode and extinguish. New methods and areas of study add and modify the consensus, but only in rare cases do they “overthrow” a paradigm. The current interest in epigenetic inheritance has spawned forth a craze in neo-Lamarckian headlines. This too shall pass.

Finally, there’s the namecheck of several biologists who are presenting an alternative to ‘selfish gene’ model, Massimo Pigliucci, Eva Jablonka, Stuart Kauffman, Stuart A Newman, Stephen Jay Gould, Gregory Wray and Mary Jane West-Eberhard. To the lay reader some of these are familiar names already. It seems that citing them is a way to bolster the case that it isn’t crazy to think that Richard Dawkins’ ideas may not be right. These aren’t all cranks. But, some of them are notable for being heterodox in their thinking. Which leads me to assert that Richard Dawkins’ views are still closer to the center of opinions among evolutionary biologists than Mary Jane West-Eberhard. That doesn’t mean that Dawkins is right and West-Eberhard is wrong, it just means implicitly ‘gene-centric’ models are still popular. There’s a reason it’s calle ‘genetics,’ and not ‘expressionetics.’

I could say much more, but I won’t. After thrashing David a fair amount I have to admit it was a pleasure to read a popular piece which cited the achievements of greats like Fisher, Haldane, Wright, and Hamilton. Though I’d warn you from taking the assertions as gospel, the article is still worth reading for its detail as a starting point for further exploration.

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