UPDATE: Dr. Philip Ward, a colleague who is an ant systematist and evolutionary biologist, has offered his critique of the Lehrer article, which I’ve added as a comment below the following:
In several previous posts (e.g., here and here), I’ve described the recent dust-up about whether kin selection (selection of “altruisitic” traits based on their effect on increasing the reproductive fitness of relatives) was an important cause of social evolution in nature, particularly in the evolution of “eusociality” (social insects with a nonreproductive caste and a reproductive queen) and of “altruism” (animals who appear to injure their own evolutionary prospects by helping non-relatives).
The controversy was inspired by a paper published in 2010 in Nature by Martin Nowak et al. (reference at bottom, other authors are Corina Tarnita and the eminent biologist E. O. Wilson), maintaining that kin selection was not a good way to analyze evolution in nature, that it was not a form of natural selection (WRONG), and that the evolution of eusociality was better explained by “group selection” (differential reproduction of groups) than by selection among relatives.
To most biologists, this controversy appears to have been settled: Nowak et al. were wrong. About a hundred and fifty biologists wrote five separate critiques that were published in Nature, along with a lame response by Nowak et al. As far as I know (and I may have missed something), no paper has been published in support of Nowak et al., and only a handful of biologists (I think David Sloan Wilson was one of them) even supported it with public statements. Referring to Nowak et al.’s lame reply to their critics, science writer Carl Zimmer said this:
Nowak et al respond to all the criticism and don’t budge in their own stand. They claim that their critics have misinterpreted their own argument. And they claim that sex allocation does not require inclusive fitness. Oddly, though, they never explain why it doesn’t, despite the thousands of papers that have been published on inclusive fitness and sex allocation. They don’t even cite a paper that explains why.
Now Jonah Lehrer has written a big piece in the New Yorker about this controversy (and about the personalities involved), “Kin and Kind.” (It’s behind a paywall, but I’ve scanned it and will send interested readers that scan if they email me.) Lehrer is a young science writer about whom I have mixed feelings. He’s a good journalist, and his piece is absorbing, but it suffers from several problems. (You may remember Lehrer as the author of another overblown New Yorker piece about the inherent untrustworthiness of science, “The Decline Effect.”)
What is my take on the piece? As I said, it’s absorbing but flawed. It will draw you in and teach you a bit about the controversy, but it ultimately suffers from Lehrer’s “he said/she said” noncommittal stance about the article, and from his unwillingness to make any judgment about the scientific issues at hand. It’s not that he’s incapable of that, I think, since he was trained in neuroscience and has written two books on that subject, but he’s more interested in controversy than scientific truth. Such is The New Yorker, which really needs to dig up some better science writers (can I suggest John Crewdson?).
Here are the problems, starting with the trivial ones:
- There is a mistake, which is no big deal in most magazines but is unforgivable in the New Yorker, which has a scrupulous policy of checking and rechecking every single fact. Referring to the criticisms of Wilson, Lehrer says, “There have been denunciations in the press and signed group letters in prestigious journals; some have hinted that Wilson, who is eighty-two, should retire.” In fact, Wilson retired some years ago.
- Another trivial thing: Lehrer refers to Wilson’s monograph on the ant genus Pheidole, as an “eight-hundred page textbook”. It’s not a textbook, for it’s not for use in any class. It’s a monograph, and no scientist, much less Wilson, would call it a textbook. (As one colleague told me, “I don’t think I’d like to take that class.”) The mention of this monograph is notable because, according to Lehrer, Wilson is prouder of it than of his famous books Sociobiology and On Human Nature, since Wilson now decries the kin selection that infused those two books. Had Lehrer done a little more digging her (he didn’t dig enough for the entire piece!), he would have found out that this monograph is not held in high regard by other ant systematists, for it doesn’t use modern methods of taxonomy: in particular, it doesn’t take into account variation within species, a sine qua non for proper analysis of species. My ant-y colleagues are of a piece in this opinion, but haven’t criticized the monograph because of Wilson’s status; one person who has criticized Wilson’s taxonomic work on ants tangentially, including the monograph, is Dr. Alex Wild, author of the superb ant blog Myrmecos (see here and here).
- The bigger problem: Lehrer doesn’t really delve deeply enough into the controversy to be able to render an opinion, and he mischaracterizes the fracas, simplistically, as a battle between the mathematicians (on the Nowak et al. side) and the biologists (all the critics):
“The mathematicians insist that their critics don’t understand the math, and the biologists insist that the mathematicians don’t understand the biology.”This is completely bogus. Many of the authors on the critiques of the Nowak et al. paper were mathematical biologists with a high degree of skill in theoretical analysis, and certainly with the ability to analyze Nowak et al.’s math (Stuart West is a notable example). And Wilson, of course, is a biologist (Lehrer does note that Wilson doesn’t understand much of his colleagues’ math.)
- Lehrer discusses haplodiploidy: the system of reproduction in many eusocial insects, which involves females laying haploid, unfertilized eggs that become males and diploid eggs fertilized by a haploid male who mates with the queen; those eggs become sterile female workers. This system produces the peculiar result that female workers share 3/4 of their genes with their sisters—instead of the regular 1/2—and hence may have more of a genetic interest in becoming sterile and helping their mother produce sisters than having their own offspring (to whom they’re related by only 1/2). It’s been known for a long time that while haplodiploidy is associated with eusociality, the association is imperfect: some non-haplodiploid species are eusocial, like termites and naked mole rats, while other haploidiploid species aren’t eusocial.
Lehrer uses this fact to dismiss the importance of kin selection in the evolution of eusociality. But he neglects a very important paper that says the opposite: a paper of Hughes et al. in Science in 2008 (reference below). That paper shows unequivocally that eusociality in insects involved kin selection: in all eight cases in the Hymenoptera (ants, bees and wasps) in which eusociality evolved, the ancestral species had queens that mated only once rather than multiply.This association was highly statistically significant.Under the kin-selection idea, single mating facilitates the evolution of sterility since females won’t be related by 3/4 if there is more than one father. The group-selection argument of Nowak et al., which doesn’t depend on relatedness, predicts that eusociality won’t be associated with whether or not females mate once or more than once in the ancestral lineage.The Hughes et al. paper is prima facie evidence that relatedness, and kin selection, facilitates the evolution of eusociality. It clearly shows that Nowak et al. are wrong, but the paper isn’t mentioned by Lehrer.
- If Lehrer had examined the math in the Nowak et al. paper, he could easily have seen that their model was incapable of judging the effects of kin selection, for it didn’t vary the degree of relatedness to see if that would make the evolution of eusociality easier. This was, I think, pointed out in some of the critiques published in Nature. Lehrer just takes a “hands-off” approach to the model. But had he dug a little, or done a little inspection guided by a modeller, he could have seen this. Instead he just throws up his hands and says the issue is unresolved. It isn’t. Nowak et al.’s model cannot say anything about whether relatedness facilitates the evolution of eusociality.
- Finally, at the end of the paper, Lehrer implicitly accepts Ed Wilson’s argument that altruism in animals must evolve by group selection rather than kin selection, for kin selection simply isn’t sufficient. That assertion is completely wrong, and Lehrer should have known that. “Altruism,” at least as “evolved altruism” that is not completely self-sacrificial, can evolve via either kin selection in groups of relatives or via individual selection if individuals can recognize and repay others who help them via “altruisitic” acts. The latter process is known as “reciprocal altruism,” and it’s probably how “unselfish” helping behavior evolved in our primate ancestors. (See my earlier post on how altruism can evolve by means other than group selection.)
Lehrer’s piece, then, suffers from a concentration on style over substance, and, most important, a failure to either dig deeply enough into the issues surrounding group selection, or a lack of understanding of those issues.
It’s not as if making his article scientifically accurate would have made it boring: after all, Lehrer does mention the work showing no statistical association between haplodiploidy and eusociality. He just fails to cite an equally important paper showing a highly significant association between multiple mating and eusociality, which shows ineluctably that kin selection is important in the evolution of eusociality. And he doesn’t talk about the ways that selection other than group selection can promote the evolution of altruism. I know Lehrer knows these other models, because I told him about them when he inteviewed me for the piece (I’m quoted in the article).
The New Yorker apparently likes Lehrer because he can write well and engagingly. But good science journalism requires more than that: it requires a deep understanding of the issues at hand and a means of conveying the substance of a controversy accurately. It wouldn’t have been hard for Lehrer to do that. But I guess the New Yorker doesn’t have any editors who can vet the science.
Oh, and the magazine needs to improve its fact-checking.
Hughes, W. O. H., B. Oldroyd, M. Beekman and F. W. Ratnieks. 2008. Ancestral monogamy shows that kin selection is the key to the evolution of eusociality. Science 320:1213-1216.
Nowak, M. A., C. E. Tarnita and E. O. Wilson. 2010. The evolution of eusociality. Nature 466: 1057-1062.