The Twitter-sphere is abuzz with the talk about David Dobbs recent article in Aeon Magazine, Die, Selfish Gene, Die! Dobbs’ article attacks Richard Dawkins (as is clear from the title). Dawkins responded here and also sent his readers to Jerry Coyne’s more detailed critique (Part I and Part II).
Steven Pinker tweeted Coyne’s blog, and also wrote to Dawkins (quoted from Dawkins’ blog):
Brilliant! This seems to be a congenital problem with science journalists — they think that it’s a profound and revolutionary discovery that genes are regulated, not stopping to think that the alternative would consist of every cell in the body synthesizing all 21,000 proteins around the clock. Part of the blame goes to molecular biologists, who hijacked the term “gene” for protein-coding sequences, confusing everyone.Sign up for This View of Life
I find it quite ironic that Dawkins, Coyne, and Pinker, the three of the most out-spoken opponents of multilevel selection, join forces again, this time to obliterate the hapless David Dobbs. (On the question of group selection, see Steven Pinker on the Edge and Jerry Coyne on his blog; check out also responses by me and colleagues on Social Evolution forum).
In my view, the key passage in the Dobbs article is this one:
For a century, the primary account of evolution has emphasized the gene’s role as architect: a gene creates a trait that either proves advantageous or not, and is thus selected for, changing a species for the better, or not. Thus, a genetic blueprint creates traits and drives evolution.
This gene-centric view, as it is known, is the one you learnt in high school. It’s the one you hear or read of in almost every popular account of how genes create traits and drive evolution. It comes from Gregor Mendel and the work he did with peas in the 1860s. Since then, and especially over the past 50 years, this notion has assumed the weight, solidity, and rootedness of an immovable object.
But a number of biologists argue that we need to replace this gene-centric view with one that more heavily emphasises the role of gene expression — that we need to see the gene less as an architect and more as a member of a collaborative remodelling and maintenance crew.
He then goes on to talk about “genetic accommodation” and describes how it might work during the evolution of running speed in a predator.
All this is interpreted by his critics as an attack on the (neo)evolutionary synthesis. Even the usually astute Razib Khan focuses on this aspect of Dobbs article (see Evolutionary orthodoxy may be boring, but it is probably true).
But I don’t see it as an attack on the evolutionary orthodoxy as much as an attack on a very special, and very limited version of it, the “gene-centric view” of G. C. Williams, popularized by Dawkins in The Selfish Gene. Remember that the main message of The Selfish Gene is that it is not individuals that are selected, but individual genes.
But that is wrong, wrong! Everybody now knows that genes are not independent agents assorting at will in genomes. Quite the opposite. Human genome, in particular, is not a mere collection of genes, it’s a massively integrated network of genes. Most human genes don’t code for proteins, they regulate each other and the small proportion of the genome that actually codes for proteins. We used to think that 98 percent of our genome was ‘junk’, because it did not code for any specific proteins (see, for example, Michael Eisen It’s not Junk blog).
The main point is that selection doesn’t just operate at the level of genes. In fact, most of the action is at the level of integrated networks of genes. And in some species, such as humans, there is an additional level, that of groups of individuals (groups of groups of genes).
Gene-centric view is a huge oversimplification of the way evolution works. And it’s a bad oversimplification. If you want to simplify things, you are better off focusing on individuals, not individual genes. But an even better approach is the multilevel one – considering how selection can act in opposite directions, depending on the level that you are looking.