I have just finished Richard Dawkin’s “The Selfish Gene.” It was necessary reading, since I have argued the unpopular position that the limits to the theory of evolution are more significant than many care to acknowledge. (See how I got sucked into this debate here.) In a nutshell, I often find that evolution arguments seem circular: Who survives? The fittest. Who are the fittest? Those who survive. So I read the book to find out: does Dawkins’ version of evolution avoid tautology?
Dawkins makes two impressive theoretical contributions. First, he argues that genes, not living organisms that host them, are the proper unit of analysis. In other words, he has a definition of the “who” in “who survives.” Second, he argues that that genes replicate themselves. Hence, he also offers an independent definition of “survives.”
Let’s just pause to consider how revolutionary these contributions are. As he himself says, “much of Darwinism is wrong” and Darwin “would scarcely recognize his original theory in this book.” (p.195) Darwin’s theory is about survival of the species! In Dawkins’ formulation, concepts like sexual selection and species are now explainable in more primitive, genetic terms. Indeed, the majority of the book is devoted to genetic explanations of a wide range of behaviors.
But limits do arise on both the “who” and the “survive” side. Are genes really the fundamental unit or do we have to consider intra-gene competition among alleles? (Alleles are smaller, sometimes overlapping, subsets of DNA sequences within a gene.) Is exact genetic copying really the only metric of survival, or are there other ways to consider similarity (e.g., some parts of the gene are more important than others)? I wonder if a future book called “The Selfish Allele” would say a gene is just an “allele survival machine” in an analogous way as Dawkins says plants and animals are just “gene survival machines.”
Another limit is in scope. Dawkins has a lengthy discussion of the “god meme” (p.192-200). Can genetics explain why celibacy persists in widespread, long lasting religions? Religious organizations benefit from the priests who devote all their attention without the distraction of family, but the genes of those priests clearly suffer. After much hand-wringing by Dawkins, I conclude that genetics play little or no role in explaining why any gene machine would choose to be celibate.
Dawkins’s genetic version of evolution is not tautological; it’s inability to explain the “god meme” is the exception that proves the rule. The “selfish allele” is an attractive but unproven challenger to the genetic version of evolution. But as the book demonstrates, genetics is a formidable champion that explains a lot more than it misses. By placing a skeptical eye on evolution, I think I’ve come to a better understanding of the broad reach (and limits) of the genetic theory of evolution.
3. et cetera