UPDATE: IMAGE PROBLEMS IN POST HAVE BEEN FIXED.
WARNING: UNBELIEVABLY WONKISH
I had a really interesting Twitter exchange with the author of an article about evolutionary biology. It's impossible to follow on Twitter because there are so many threads, so I thought (for my own benefit as much as anyone else's) I'd try to piece together the pieces here.
David Dobbs wrote this article on Aeon.co: "Die, selfish gene, die: The selfish gene is one of the most successful science metaphors ever invented. Unfortunately, it's wrong"
I've been a fan of the Selfish Gene, both the book and the metaphor, since college, so I read Dobbs's piece with great interest and anticipation. I was disappointed that either it did nothing to prove that the metaphor is wrong, or I misunderstood it.
I wasn't the only one who reacted negatively. The article started quite a firestorm in the evolultionary biology world, and some of the brightest stars attacked it, including population geneticist Jerry Coyne, who wrote a two part take-down, evolutionary psychologist Steven Pinker, and the big man himself, the inventor of the Selfish Gene metaphor, Richard Dawkins.
I took to Twitter to express my confusion…
And I was surprised that the author David Dobbs answered my tweet. (I had not mentioned him in my original tweet.)
I replied:
Kevin Maroney, who really seems to know his stuff, chimed in.
Dawkin's blog post specifically had specifically refuted that, saying that it was always intended to include the fact that genes are complex, work with each other, and can create a multiple of traits depending on the circumstances, so I tweeted a link to his post.
Dobbs confusingly agreed that Dawkins recognizes this. I didn't understand his point at the time, but I now think he was saying that the MEME, i.e., the popular understanding of his theory, not the theory itself, doesn't recognize this.
Then this exchange:
I quoted his title for the thesis.
This was surprising. Does he really think he doesn't have to defend the title of his piece as a distillation of its premise? He says in huge font on top his article: "It's wrong." Dawkins had written that the most controversial part of the article was the way Dobbs phrased this — and that it was a disingenuous attempt to generate a fight where none exists, calling it "adversarial journalism.'
At this point I realized I'm engaging a writer who's written a very interesting article I'd love to know more about, and I'm arguing about semantics and superficial stuff. I had a very real question that could get to the substance of whether or not I agreed with the group of scientists Dobbs wrote about. I honsetly didn't understand an example he used that supposedly showed how the manner in which an organism's body changed during its lifetime (phenotype) could affect the evolution of its species (the genotype of future generations). (I think?)
"For example, suppose you’re a predator. You live with others of your ilk in dense forest. Your kind hunts by stealth: you hide among trees, then jump out and snag your meat. You needn’t be fast, just quick and sneaky.
You get faster. You mate with another fast hunter, and your kids, hunting with you from early on, soon run faster than you ever did
Then a big event — maybe a forest fire, or a plague that kills all your normal prey — forces you into a new environment. This new place is more open, which nixes your jump-and-grab tactic, but it contains plump, juicy animals, the slowest of which you can outrun if you sprint hard. You start running down these critters. As you do, certain genes ramp up expression to build more muscle and fire the muscles more quickly. You get faster. You’re becoming a different animal. You mate with another fast hunter, and your kids, hunting with you from early on, soon run faster than you ever did. Via gene expression, they develop leaner torsos and more muscular, powerful legs. By the time your grandchildren show up, they seem almost like different animals: stronger legs, leaner torsos, and they run way faster than you ever did. And all this has happened without taking on any new genes.
Then a mutation occurs in one grandkid. This mutation happens to create stronger, faster muscle fibres. This grandchild of yours can naturally and easily run faster than her fastest siblings and cousins. She flies. Her children inherit the gene, and because their speed wows their mating prospects, they mate early and often, and bear lots of kids. Through the generations, this sprinter’s gene thus spreads through the population.
Now the thing is complete. Your descendants have a new gene that helps secure the adaptive trait you originally developed through gene expression alone. But the new gene didn’t create the new trait. It just made it easier to keep a trait that a change in the environment made valuable. The gene didn’t drive the train; it merely hopped aboard. Had the gene showed up earlier (either through mutation or mating with an outsider), back when you lived in the forest and speed didn’t mean anything, it would have given no advantage. Instead of being selected for and spreading, the gene would have disappeared or remained in just a few animals. But because the gene was now of value, the population took it in, accommodated it, and spread it wide.
This isn’t the gene-centric world in which genotype creates phenotype. It’s a phenotype accommodating a new genotype by making it relevant."
This was my opportunity to clarify that, and get a better understanding.
He didn't answer, so I tried again.
So I came away from out discussion with this:
1. When Dobbs says the Selfish Gene concept should "die," he's referring to the popular, simplest conception of the concept, not anything Dawkins has ever thought or written. Okay.
2. What he apparently means when he says that selfish-gene proponents don't take into account the fact that organisms change their phenotype to adapt to their environment is not that such changes have any effect on evolution, but that… I don't know, maybe: It's cool and they should acknowledge that.
Anyway, it was fascinating to have the opportunity to clarify this, and I do appreciate David's time. Twitter is far from the best forum to have a discussion like this, but without Twitter there's no way I could have had this substantive conversation with a writer whose piece I was very curious about.
</wonk>
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