After reading Dawkins’ The Ancestor’s Tale, I was all excited to read about some more specific topics in evolutionary theory. His The Selfish Gene was the obvious next step. The fundamental idea is a great one, although of course less revolutionary now than I guess it was in the 1970s when it was published: rather than trying to explain the evolution of traits in terms of group selection, or kin selection, or individual selection, we should turn the problem inside out and look at the actual thing that not only gets replicated perfectly but also controls the trait itself: the gene. When you do this, a lot of paradoxes of the form “how can this behavior benefit the individual?” or “how can this behavior benefit the species?” make a lot more sense.
As I said, this book was originally published 30+ years ago and it hasn’t been updated much, but I didn’t find that that affected my reading much, besides some obviously completely obsolete analogies to contemporary computing power. I don’t know how much has changed since the time it was written, but the arguments seemed to hold up pretty well.
The book was quite interesting, although I was hoping for some more quantitative analysis of various scenarios. He does analyze some situations mathematically, but there was a bit too much of “This seems to contradict the theory, but we can explain it away with this clever hypothesis,” which is too unfalsifiable for my tastes.
It isn’t until the last couple of chapters that things really take off. The penultimate chapter is about how it is possible for altruism to evolve, and the final one goes even further than to say “let’s concentrate on the gene instead of the individual as far as evolution goes”; it asks why we really have individuals at all, which is a question that really blew my mind.
The individual organism is something whose existence most biologists take for granted, probably because its parts do pull together in such a united and integrated way. Questions about life are conventionally questions about organisms. Biologists ask why organisms do this, why organisms do that. They frequently ask why organisms group themselves into societies. They don’t ask — though they should — why living matter groups itself into organisms in the first place. Why isn’t the sea still a primordial battleground of free and independent replicators? Why did the ancient replicators club together to make, and reside in, lumbering robots, and why are those robots — individual bodies, you and me — so large and so complicated?
Awesome. He goes on to list some interesting advantages that genes get by building organisms around themselves, which I will not spoil here. Apparently this last chapter is basically a summary of yet another Dawkins book, The Extended Phenotype, so at some point I suppose I have to read that too. But for now I have probably read enough evolution books for a while.
Summary: a lot of cool ideas, and a few mind-bending ones, though my ideal version of this book would have cut out 50% of the material that didn’t fit into those categories. In any case, it is a total classic of modern popular science writing (and originated the concept of memes, though it has gotten kind of corrupted since then), and is worth reading for that reason alone.
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