The Boston Globe on kin selection
But of course the whole controversy isn’t really a fit subject for a newspaper article, for it’s not a controversy at all: it’s simply two guys and a woman deeply misunderstanding evolution and trying to parlay this misunderstanding into fame. Had an identical paper not borne the names of Martin Nowak and E. O. Wilson, Neyfakh wouldn’t have written this piece.
Some quotes:
On a recent Monday afternoon, the distinguished Harvard biologist Edward O. Wilson was at his home in Lexington, talking on the phone about the knocks he’s been taking lately from the scientific community, and paraphrasing Arthur Schopenhauer to explain his current standing in his field. “All new ideas go through three phases,” Wilson said, with some happy mischief in his voice. “They’re first ridiculed or ignored. Then they meet outrage. Then they are said to have been obvious all along.”
As one of my colleagues said dryly when he read that, “Wilson seems to have missed the point that you need a new idea before you can get to go through those phases!”
“Kin selection is wrong,” Wilson said. “That’s it. It’s wrong.”. .
Over the course of subsequent decades, Wilson came across evidence that made him doubt the connection between genetic relatedness and altruism. Researchers were finding species of insects that shared a lot of genetic material with each other but didn’t behave altruistically, and other species that shared little and did. “Nothing we were finding connected with kin selection,” Wilson said. “I knew that something was going wrong — there was a smell to it.”. . .
Saying that kin selection doesn’t feed into eusociality (societies in which a sterile worker caste tends one or a few reproductive individuals) because some haplodiploids aren’t eusocial and not all eusocials are haplodiploid is like saying that smoking isn’t associated with lung cancer because some smokers don’t get lung cancer and some people who get lung cancer didn’t ever smoke. The question is whether there is an apparently causal association between relatedness (i.e., via inclusive fitness) and altruism. And there is. We’ve long ago realized that haplodiploidy may not be the key factor in the evolution of eusocial insects, but relatedness certainly is. The ancestors of all eusocial insects, including non-haplodiploids like termites, mated only once rather than multiple times, which increases relatedness among their brood; this is exactly what you’d predict if relatedness were important here. Further, “cooperative breeding” in birds, in which the young stay at home and help mom and dad rear the next batch of their brothers and sisters, is correlated with lower promiscuity of the parents. That’s again explained by inclusive fitness, for you’d have less “genetic interest” in rearing future siblings if they had a different father from you (that would reduce your relatedness to future siblings by half).
Anyone who says that “kin selection is dead” is deeply muddled. What is parental care, after all, but a special case of kin selection? Why do Ma and Pa Eagle stay at home and tend the eaglets until they fledge? Why don’t they just go off and build another nest? The reason, of course, is because each parent is related by half (50% sharing of genes) with each chick, so their genes for parental care will be carried in those chicks. This is simply the most obvious case of kin selection, but the principle surely applies to lesser degrees of relatedness.
Dawkins makes strong judgment on the paper:
Richard Dawkins, who played a crucial role in popularizing kin selection with his 1976 book, “The Selfish Gene,” said last week that he has “never met anybody apart from Wilson and Nowak who takes it seriously.” . .
I think the other Wilson—David Sloan Wilson—takes it seriously.
Wilson is not arguing that members of certain species don’t sacrifice themselves for the benefit of their relatives. They do. But it’s his position that kinship and relatedness aren’t essential in causing the development of advanced social behaviors like altruism — that the reason such behaviors catch on is that they’re evolutionarily advantageous on a group level. That socially advanced organisms end up favoring their kin, Wilson argues, is a byproduct of their group membership, not the cause.
“It’s almost universally regarded as a disgrace that Nature published it,” Dawkins said. “Most people feel the reason they published it was the eminence of Wilson and Nowak, not the quality of the paper.” . .
Dawkins is right, of course. As I’ve said before, if the paper were published by three schmoes from Unknown University, it would have been rejected out of hand. Nature screwed up badly on this one, but of course the editors are rubbing their hands and chuckling over all the publicity they’ve gotten—at the expense of good science.
And yay for me and Dave Queller:
For Wilson to reject kin selection this late in his career has bewildered his many admirers. “It’s sad — he’s already an enormously famous and respected scientist, and it just sort of tarnishes him in people’s eyes,” said Jerry Coyne, the University of Chicago biologist who has written disapprovingly of Wilson’s latest work on his blog. Yet Wilson said he doesn’t have a choice in the matter. “I think that’d be a pretty poor scientist, who couldn’t reverse his view from new evidence,” he said. . . .
Many biologists find these assertions baffling. Said David Queller, a biologist at Rice University who spearheaded the letter to Nature that was signed by 136 other scientists: “At some really fundamental level I don’t understand what Ed Wilson is trying to get across, and I think that’s the response of most of the community.”
Nowak arrogantly responds:
That’s exactly the problem, according to Nowak, whose new book, “SuperCooperators,” co-written with Roger Highfield, summarizes his work as a mathematician on the origins of advanced social behavior. “They don’t know what they’re arguing against,” Nowak said recently at his office, where an oversize print of the Nature cover hangs on the wall. Specifically, Nowak explained, the critics don’t understand the math, and moreover, they don’t realize that the math is the most important part. . .
Yeah, right: 140 biologists, many of whom are mathematical biologists or deeply involved in theory (Dave Queller and Stuart West are just two among many), all fail to grasp what they’re arguing against! Well, those who have vetted the math realize that Nowak et al.’s model says absolutely nothing about a possible connection between relatedness and the origin of eusociality. That’s because their own model does not explore what happens when one varies the degree of relatedness! It therefore can’t say anything about whether relatedness is important in the evolution of eusociality. Responding to this, my colleague remarked, “This is like making three types of jam, where two are nice and one is gross (strawberry, gooseberry and oak leaf), and then saying that because the amount of sugar used wasn’t varied in these three jams (all were about 50% sugar) that sugar doesn’t matter to whether the jam tastes nice.”
Re whether kin selection is, as Nowak et al. assert strongly, something completely different from natural selection, Richard and I had something to say. I’m particularly proud of my analogy:
At a very basic level, critics feel Wilson and his coauthors are wrong to treat kin selection as something separate from natural selection. As Dawkins explains it, kin selection is not a distinct process but a necessary consequence: a subset, rather than an add-on. “What they’re missing is the logical point that kin selection is not separable from neo-Darwinian natural selection,” Dawkins said. “To separate them off would be like talking about Euclidean geometry without talking about the Pythagorean theorem.”
Coyne put it even more simply: “It’s like saying that Chardonnay is not wine.” . . .
Wilson again argues for the non-importance of relatedness:
Wilson is not arguing that members of certain species don’t sacrifice themselves for the benefit of their relatives. They do. But it’s his position that kinship and relatedness aren’t essential in causing the development of advanced social behaviors like altruism — that the reason such behaviors catch on is that they’re evolutionarily advantageous on a group level. That socially advanced organisms end up favoring their kin, Wilson argues, is a byproduct of their group membership, not the cause. . .
Well, if you want to see if kinship is a causal factor in the evolution of any trait, you must make a model in which group sizes and dynamics are the same but the degree of kinship varies. That is exactly what Nowak et al. did not do. Wilson has no idea what he’s talking about here.
And watch out for more evolutionary psychology to come!
So far, Wilson has stopped short of extending his new ideas about the evolution of social behavior to the human race. But that’s not going to last. Asked last week whether group selection happens in humans, Wilson said, “Yes, emphatically.”
“Human beings have an intense desire to form groups, and they always have,” Wilson said. “This powerful tendency we have to form groups and then have the groups compete, which is in every aspect of our social behavior…is basically the driving force that caused the origin of human behavior.”
Wilson will elaborate on this view in his next project, a book he’s tentatively calling “The Social Conquest of Earth,” which he said will be published by W. W. Norton next year. In it, he said, he will explain how socially advanced species have come to dominate the earth, and will lay out a “reexamination of human evolution” informed by his recent turn towards group selection.
It is possible that some kind of group selection for altruism occurred in early human lineages, based on differential reproduction of groups with different degrees of “morality.” But it could also have involved kin selection if, as is likely, members in early human social groups were related. And the evolution of moral codes and behaviors could also have involved individual selection: individuals who behaved nicely could have reaped reproductive benefits since groups were small and individuals intimately acquainted with each other, so they could remember and reward those who were nice, with the expectation of getting the same by behaving the same. Regardless, most animals don’t live in such small groups nor have a memory for interpersonal dynamics. And of course we know, from other observations (evolution of sex ratio, preferential care for relatives, cooperative breeding, etc.) that kin selection certainly does operate in nature.
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