This is a decades-old argument in evolutionary theory that many thought was settle late in the twentieth century, but it has recently reared its head again.
One of the lead proponents of resurrecting group selection has been E. O. Wilson. You can read reports of Wilson’s recent presentations here and here. Steven Pinker recently jumped into the fray.
Almost everything that I read on both sides of this issue is highly conceptual stuff. Models are formulated. Reasons are advanced. It’s all very abstract and with a lot of jazz hands. It’s been frustrating for me, and keep in mind, I like this stuff. I’m co-teaching a graduate class in evolution right now. I can’t imagine what a non-specialist makes of this stuff.
Largely absent in these discussions are terms like “hypothesis,” “prediction,” and “test.”
What I would love to see would be for those in this argument to say, “Here is an organism with that routinely lives in groups and benefits from being in a group. If group selection is occurring, we would expect to see this much more reproductive success than you could account for by individual success alone.”
If not reproductive success, gene frequencies, or some other measures.
And I would love to see these experiments made for animals other than humans. There are too many pitfalls that can trap even the wariest researcher when thinking about humans. Meerkats might be a good case study, if this interview with Tim Clutton-Brock is anything to go by. He rejects kin selection as the main explanation for cooperation in meerkats.
I started off thinking that the whole thing ran through kinship. Kinship is obviously there but these group-related benefits are obviously fantastically important, and my suspicion is that in most of the highly co-operative mammals, things like naked mole rats and African wild dogs, the same pattern holds. They're related to each other, but there are lots of other social mammals that are related to each other which aren’t advanced co-operators. And the unusual thing of the advanced co-operators is that they live in habitats and they live in ways where they’re really dependant on other members of the groups.
Note, though, that “benefiting from being in a group” – which Clutton-Brock is describing – is not the same as “group selection.”
Those who are advocating that group selection is a major evolutionary force need to articulate a research program.
The value of having a research program is often underestimated. It’s not enough to be right in principle; you have to suggest experiments that you can do to test them. A lot of experiments.
For example, there are a lot of different ideas out there for how to define species. But the biological species concept (species are non-interbreeding) suggested a research program while other species concepts did not (Coyne and Orr’s Speciation). The discovery of a major impact at the K-T boundary ( Alvarez et al. 1980)suggested a research program. Eldredge and Gould’s punctuated equilibrium (1972) suggested a research program, and lots of productive science arose from that. Gould and Lewontin’s Bauplan (1979) didn’t readily suggest experiments, and languished.
Wilson developed a research program when he published Sociobiology (1975). That book (perhaps along with The Selfish Gene; Dawkins 1976) galvanized animal behaviour. Ethologists probably spent a good 15 years or so exploring and testing ideas arising from those books.
I have only vague ideas about what a group selection research program would look like. But then, it’s not my job to spell out the research to do: that burden lies with those who are advocating group selection is important in evolution.
Additional, 24 June 2012: The Guardian has noticed. They frame this as a “Let’s watch the famous guys fight,” though, which is disappointing.
Additional, 25 June 2012: Jerry Coyne is disappointed by The Guardian piece.
Alvarez LW, Alvarez W, Asaro F, Michel HV. 1980. Extraterrestrial cause for the cretaceous-tertiary extinction. Science 208: 1095-1108. doi: 10.1126/science.208.4448.1095
Coyne JA, Orr HA. 2004. Speciation. Sunderland, MA, Sinauer Associates.
Dawkins R. 1976. The Selfish Gene. Oxford, Oxford University Press.
Eldredge N, Gould SJ. 1972. Punctuated equilibria: An alternative to phyletic gradualism. Models in Paleobiology. TJM Schopf (ed.), pp. 82-115. San Francisco, Freeman, Cooper and Company.
Gould SJ, Lewontin RC. 1979. The spandrels of San Marco and the Panglossian paradigm: A critique of the adaptationist programme. Proceedings of the Royal Society of London. Series B. Biological sciences 205(1161): 581-598. DOI: 10.1098/rspb.1979.0086
Wilson EO. 1975. Sociobiology: The New Synthesis. New York, John Wiley.
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