I’ve been reading The Ancestor’s Tale by Richard Dawkins…well, just now I’ve been reading The Passage, which is mostly a ripoff of The Stand with vampires instead of the flu, but I want to talk about the Dawkins book.
The Ancestor’s Tale is about evolution. The idea is that we are walking back in time, meeting various critters as our line of ancestry joins theirs, and, on the model of Chaucer’s Canterbury Tales we get stories from some of these “pilgrims,” e.g. The Velvet Worm’s Tale. The whole Chaucer thing seems like a loser move to me; nobody really wants to hear, say, a fungus tell a story (when is the last time you willingly invited a slime mold to a dinner party?). Plus, the stories in The Ancestor’s Tale are more or less about the tellers, which is not at all Chaucer’s bag: his Miller tells a very funny dirty story about a reeve, and the Reeve retaliates with a story about a miller that is dirty but about as funny as Haley Barbour’s press secretary.
Still, the idea of going backward in time, starting with us and ending with bacteira, is not without its point. Dawkins is trying to avoid the overpowering impulse to make evolution into a story of progress. Dawkins shows that even respectable scientists can fall into this trap, seeing a development (say, the lungfish-type animals that first ventured onto land) as an attempt at some future goal (colonizing the land). Of course mutation and natural selcetion never look to the future and never have a plan, but try telling a chronological story without making it sound as though they did–it’s not easy. Dawkins has resorted to this rather modernist narrative strategy as a way to discipline the teleological urge, and I respect the project, though one occasionally misses the fun of moving forward in time.
Of course it’s not just biologists who struggle with the lure of progress. I was reading The Great Transformation by Karen Armstrong, a book about religion in the last milennium BCE, and was surprised to find her talking about this or that “advance in spirituality.” I envision newsreel footage of the March of Spirituality, with the voice-over touting the new Ahimsa, India’s latest gambit to keep ahead of the Confucians. Armstrong is a smart person, but the idea of religious history as progress is just weird. But I digress.
Dawkins, who made his name many years ago with The Selfish Gene, still has interesting things to say. One is a critique of the notion of species; the basic definition is that two critters belong to the same species if they can have fertile offspring, and if not, not. The problem is that this isn’t nearly as clear a boundary as it sounds, because there is a continuum from one species to the next. For example, in Britain there are gulls with black backs and gulls with gray backs, which do not interbreed, and seem clearly to belong to diiferent species. But if you travel west, you find black-backed gulls who gradually get more and more like the gray-backed ones, until, by the time you’re back in Europe, they are the gray-backed ones. I may have the details backwards, but the point remains that there is no place to draw a line: A breeds with B, B breeds with C, C breeds with D, but A doesn’t breed with D…so where’s the species boundary?
This is kind of a cool idea in itself, but it is very important because it is the story of evolution. If you follow our ancestors back in an unbroken line about 6 million years to where we join the ancestors of the chimps, and then forward along the chimp line, we have a chain each link of which joins two animas of the same species, indeed two almost identical animals, and yet we are not chimps. And you can do the same for monkeys, crabs, bacteria–there is never a good place to draw the line of speciation. It’s obvious, but I had never thought about it in just that way.
I also got something out of Dawkins’ chapter on race, though it is mostly pretty cringeworthy (he seems obsessed with the fact that “black” people are not actually black–do Oxford profs know what “Duh” means?). According to Dr. D, humans are a rather homogeneous group, genetically, and most of our genetic variation is among the different peoples of Africa. On the inside we are very similar, but the variations that have developed produce quite striking surface differences. Why? The suggestion is that this is a result of sexual selection: as human groups become separated, they become attached to anything that differentiates them from their “foreign” neighbors, so that the people who are most unlike the out-group in appearance are most likely to attract mates. In other words (though Dawkins doesn’t put it this way), our preoccupation with group identity and solidarity has led to physical differentiation: “race,” to the extent that it exists at all as a genetic reality, is largely a by-product of ethnicity.
[Update] I should mention that Dawkins also cites the usual climatological source of surface diversity, that humans have a wider range of habitats than many animals, including tropical regions where it pays to be dark and northern ones where it doesn’t.]