Sunday, 26 February 2012

Wilson: The Social Conquest of Earth

Edward O. Wilson has a new book coming out on the topic of social behaviour: The Social Conquest of Earth. It seems to focus on human social behaviour.

The book also seems to focus on the topic of group selection. Wilson has touched on this topic before - with Superorganism, and some papers with David Sloane Wilson: Evolution “for the Good of the Group”, Survival of the selfless and Rethinking the theoretical foundation of sociobiology. These joint papers seem to be largely the voice of David Sloane Wilson to me. There was also a recent paper apparently bashing kin selection: The evolution of eusociality Martin A. Nowak, Corina E. Tarnita and Edward O. Wilson (with supplement). The New Yorker also recently published "Kin and Kind - a fight about the genetics of altruism" on the topic. 137 authors replied in Nature, saying, basically: Eugh.

The Wilsons seems to have got hold of the idea that eusociality involves group selection. In a sense it does, but group selection doesn't have a monopoly on viewing colonies as individuals. Social insect colonies can also be seen as the product of kin selection and manipulation (by queens and/or workers). David Sloane Wilson delights in claiming that kin selection is a special case of group selection. However, models of the two ideas are equivalent. However, shared genes and differential reproductive success of groups still seem to be pretty different explanations for why cooperation takes place - and kin selection between close relatives seems to account for most of the observed effect, while distantly-related group members are relatively insignificant.

Quietly muddling together kin selection and group selection seems to be a common problem. In Unto Others, David Sloane Wilson claims the evolution of virality to be one of the best documented cases of group selection - yet this heavily involves kin selection. The other example given there - female-biased populations - also seem to have been convincingly explained as cases of kin selection between close kin. The usual examples that are trotted out - slime molds, social insects, chickens, multicellularity - all seem to be better explained as cases of kin selection acting between close kin. There do not seem to be any examples of group selection in nature that are not better explained as cases of kin selection acting on close kin.

If you give group selection credit for kin selection's moves, then no wonder group selection looks as though it is important. The real issue here is surely whether a theory of group selection adds anyhing - after kin selection acting on close relatives is taken into account.

The blurb for the new book says:

Refashioning the story of human evolution in a work that is certain to generate headlines, Wilson draws on his remarkable knowledge of biology and social behavior to show that group selection, not kin selection, is the primary driving force of human evolution.
The "primary driving force of human evolution"? What's that, then? Human culture, perhaps?

Kin selection is a proven and important theory, explaining important phenomena such as parental care - while group selection is still a fringe theory that has hardly been proven to be responsible for anything. Unless of course you redefine the term "group selection" - to refer to kin selection, reciprocal altruism, virtue signalling, manipulation - and a bunch of other things - in the manner that David Sloane Wilson advocates - in which case this turns into more of a fight over terminology than one over facts.

Looking at the paper with Nowak, it looks as though Wilson is not doing much more than claiming that multi-level selection theory is more general than kin selection - which is usually regarded as not being correct. More usually the "new" group selection and kin selection are regarded as being broadly equivalent.

Wilson discusses the contents of the book a little here: E. O. Wilson’s Theory of Everything.

There's an interview with Carl Zimmer here: What Does E.O. Wilson Mean By a "Social Conquest of the Earth".

I have mixed feelings about Wilson's work in this area. Some of the "group selection" points seem correct, other ones seem more dubious. The group selection controversy is interesting material. However, I am inclined to side with Stuart West (2009) on this whole issue: the "new" group selection is already covered by the math of conventional inclusive fitness theory.

Update 2012-04-02: The book is now out. Here it is on Google Books.

I looked at the section devoted to kin selection: Wilson starts off with what appears to be a misquotation from Ernst Fehr and Simon Gachter (2002):

Unlike other creatures, people frequently cooperate with genetically unrelated strangers, often in large groups, with people they will never meet again, and when reproductive gains are small or absent. These patterns of cooperation cannot be explained by the evolutionary theory of kin selection and the selfsh motives associated with signalling theory or the theory of reciprocal altruism.
Of course, such patterns could be explained by cultural kin selection. Or the theory that kin selection could have given us these instincts while our ancestors were in small tribes. These folk also have a relavant explanation of why humans are so generous, even in one-shot interactions: The evolution of direct reciprocity under uncertainty can explain human generosity in one-shot encounters by Andrew W. Delton, Max M. Krasnow, Leda Cosmides & John Tooby.

Wilson then goes on to say:

Kin selection, as I have pointed out, cannot be the solution to this paradox. It might be thought to have worked in the bands of the early hunter-gatherers, where because of small numbers, kinship of the members was close. But mathematical analysis has revealed that kin selection of itself is inoperable as an evolutionary dynamical force. When closely related individuals come together such that cooperators are more likely to meet other genetic cooperators, the result will not, by itself promote the origin of cooperation. Only group selection, with groups containing more cooperators pitted against groups containing fewer cooperators, will result in a shift at the level of the species towards greater and wider instinctive cooperation.
So, it seems that Wilson is relying on "mathematical analysis" - and apparently from an unspecified source - for his critique of kin selection. OK - so: which mathematical analysis.

In fact, I think - even without seeing the analysis - that it is pretty clear that Wilson's claim that "kin selection of itself is inoperable as an evolutionary dynamical force" is false. As is the claim that "Kin selection is wrong." For example, it really does make a difference if you find out that someone is a relative.

One remaining question is whether being spectacularly wrong is a good way of selling a lot of books.


Edward O. Wilson, Harvard University on Charlie Rose in 2012.

Wilson's position on the topic of kin selection looks very shaky to me in this interview. It appears as though he is stuck in a bit of an intellectual bubble. He probably shouldn't be criticising Richard Dawkins like that - Richard is really just stating the conventional position here.

Here's Wilson on FORA TV:

I'm going to be a little bit strong worded about the 40 years - the four decades that we have laboured and spun our wheels with kin selection theory - and I'm guilty of that too because in my first books on sociobiology I adopted it as a good genetic expanation - and those words are: We now have got to clear the wreckage of kin selection off the road so we can move ahead. Now that that's being done what I have now written here will be much more likely to come to pass.

This is just nonsense. Wilson doesn't seem to know what he is talking about. The critique offered in the FORA TV is revealing. Wilson just doesn't understand the issue. My assessment is that group selection enthusiasts are rather unfortunate to have Wilson, Novak and Tarnita on their side.



  • Wilson, E. O. (2012) “The Social Conquest of Earth” FORA TV.
  • Wilson, E. O. (2012) Where does good come from?



    1. There was an error in publishing. This is the right comment:

      I guess it would be better to use the term "Multilevel selection" coined, as far as I know, by another Wilson (D.S Wilson).
      Perhaps the divisions between different levels of selection are somewhat artificial. Nature doesn´t have the necessity to draw clear frontiers between levels of selection. We do.
      We know that the basic level of selection isgene-level selection. We can start there and see another levels of selection as an emergent property. Like an "as if".
      "Selfish" gene-level selection may account for individual-level selection and for kin-selection. And these levels can account for an "as if" group selection under particular circumstances (for example, Boyd and Richerson showed how conformity bias an prestige bias can enhance the uniformity within groups and diversity among groups).
      It is useful for us to use these denomination so that we know what we are speaking about, but the core of everything is the selfish replicator-level selection.

      Juan Alfonso del Busto

    2. "Multilevel selection" seems to me to be the most obvious term to use for the Wilson/Price idea. However, D. S. Wilson wants to call it "group selection". That is understandable - but it is also a source of much confusion.