Edward O. Wilson, the founding prophet of sociobiology, has long been a controversial figure, starting with demonizing as a racist for his 1970′s claim that there is an evolutionary basis to human behaviour.
A recent article in the Boston Globe (April 17, 2011) has brought Wilson’s latest scientific spat into the general spotlight. This time, he’s trying to unconvert the converted. Of such things are science wars made.
Now that almost everyone has accepted the idea that there is, indeed, an evolved structure to human nature, the old warrior is back, this time challenging kin selection altruism, the key tenet of sociobiology. Wilson, along with mathematical biologists Martin Nowak and Corina Tarnita, restirred this pot last summer when they published “The evolution of eusociality” in Nature.
Their chief contention was that the behaviour of eusocial species — species that cooperate to raise their young in non-parental groups, typically bees and ants — is the result not of kin selection but rather of “ordinary” selection, but at the group level.
Wilson’s turnaround is equivalent to Barack Obama’s announcing that he will run for reelection as a Republican. After all, it was Wilson who “made” sociobiology in the first place, basing it firmly on kin selection altruism. Over the last forty years, kin selection has become “gospel”; now its first, greatest proponent is claiming that it’s not as central or important as everyone else now believes.
Not bad for an 81-year old, to be still relevant, after all these years. Or, if the volume and breadth of the negative reaction to his latest idea is any indication, still crazy after all these years.
Last month, Nature published a series of rebuttal letters, one of them signed by 137 scientists who say that Wilson has got it wrong, that he doesn’t understand the science he started. The King is dead, long live the King, science style.
On his blogsite, Jerry Coyne goes so far as to write that (a) Nature would never have published such a weak article if it had come from authors who weren’t famous as good scientists; (b) the article is bad science; (c) the authors wrote it so that they could become famous. I don’t know about you, but aren’t both combinations (a,b) and (a,c) contradictions?
Of course, I’m not competent to judge the worth of the details of the science involved, but I do suspect that the violence of the negative reaction has much to do with the objectors’ perception of a threat to the bases of their own specialties. It’s unfortunate that so much of the criticism (at least what I’ve been finding and reading online) has so strong an emotional content. Perhaps it just seems that way because I’m not able fully to understand the scientific objections and thus overplay the more general reactions. But I’m not alone in noting that many of the criticisms have at least an undertone of anger and betrayal, no matter what the science actually may be.
And there is some dispute over just what that science is. Coyne is not alone in charac-terizing Wilson & Nowak (Tarnita is a young postdoc working with Nowak, as far as I can tell) as claiming that kin selection is unimportant. Coyne argues that what’s “new” in the Wilson, et al paper isn’t new (“But we’ve known all this for years!”) and that what’s really new, downplaying the role of kin selection, is wrong:
The main problem with the Nowak et al. paper is this: they see the failure of asymmetrical relatedness to explain social insects as a general failure of kin selection to help us explain those groups— or anything at all. That’s just wrong.
But a number of others, including some of those posting comments to Coyne’s blog, have pointed out that the Nature article doesn’t trash kin selection. Rather, it places it in a less prominent place by instead emphasizing group selection at the hive or colony level.
What’s at the heart of the scientific objections to what Wilson & Nowak actually say, if I’m reading the commentary correctly, is that in the authors’ new description social groups form first, and kin selection is a secondary outcome of the natural operation of standard evolution on these populations of related individuals. Anthills and beehives are the usual, and the best, examples. For reasons having little to do with kin selection, these insects form colonies of related individuals (they’re all offspring of one fertile female, the queen, so they’re all related). If the colonies form before kin selection operates, then of course kin selection can’t be the driving force of colony formation — and there goes, by analogy at least, the leading theory for the origins of human social groups.
Although Wilson & Nowak explicitly exclude human groups from their formulation, they do acknowledge that ” parallels with the scenarios of animal eusocial evolution exist, and they are, we believe, well worth examining.” It’s this obvious extension to human social grouping, I believe, that is the root cause of the vehemence and rancor in the academic gang-up on the authors. Say what you like about my insect friends, but keep that heresy away from me!
To put what Wilson & Nowak actually claim on the record here, they write that eusocial evolution occurs in a succession of stages:
(1) the formation of groups. (2) The occurrence of a minimum and necessary combination of pre-adaptive traits, causing the groups to be tightly formed. In animals at least, the combination includes a valuable and defensible nest. (3) The appearance of mutations that prescribe the persistence of the group, most likely by the silencing of dispersal behaviour. … (4) Emergent traits caused by the interaction of group members are shaped through natural selection by environmental forces. (5) Multilevel selection drives changes in the colony life cycle and social structures, often to elaborate extremes.
For Wilson, groups come first. Over evolutionary time, groups that cooperate outcompete groups that don’t. Cooperation is selected because it helps the group survive. Without the group, socially-dependent individuals don’t survive.
In the Boston Globe interview, Wilson put the implications for understanding the evolution of human cooperation this way:
Human beings have an intense desire to form groups, and they always have. 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.
Whether or not Wilson & Nowak and their critics will continue to compete until one side triumphs, or learn to cooperate again, finding truth in some as yet undetermined middle ground, is still to be decided.