Wilson and Dawkins and Group Selection …

Jerry Coyne is talking about David Sloan Wilson and how Wilson’s going after Dawkins for two reasons. First, Wilson goes after Dawkins for seemingly not looking enough at the potential evolutionary benefits of evolution, and second he complains that Dawkins is ignoring the obvious that group selection is the answer for things like altruism.

I don’t want to talk much about that. What I want to talk about is the objections that Coyne raises against Wilson’s group selection theory:

Dawkins’s argument against the efficacy of group selection was that this form of selection is usually unsuccessful because groups are vulnerable to subversion from within by those selfish replicators. That is, “cheating” replicators that are “good” for individuals but bad for the group as a whole will tend to propagate themselves. Yes, altruism may help groups propagate, but altruistic groups are susceptible to invasion by cheaters unless the “altruism” is based on kin selection or individual selection via reciprocity.

That’s the main one, but he goes on to fill in more later:

Dawkins’s (and my) beef with group selection as a way to evolve traits that are bad for individuals but good for groups is that this form of selection is inefficient, subject to subversion within groups, and, especially, that there’s virtually no evidence that this form of selection has been important in nature.

Let me deal with the two minor ones before getting back to the main event. Starting with the last one, we can see that it’s a bad argument, because what Coyne is doing here is saying that one of the reasons to reject the examples Wilson’s giving of cases where group selection has been important in nature is … that you haven’t found examples of cases where it has been important in nature. Except, perhaps, for the specific cases Wilson is citing. You can’t in any way reasonably claim that the fact that you haven’t found examples of it yet means that you can dismiss this proposed example. This example has to stand on its own merits, because it might be the sort of example that you’re looking to find that will prove that it has been important. Taken to the logical extreme, this sort of attitude may mean that if you can find any other explanation for it using the more “normal mechanisms” — no matter how complicated or ludicrous that explanation might seem — then that will be taken because the new mechanisms haven’t been proven yet, which is strikes me is something that naturalists pull on the supernatural all the time. Therefore, it’s not worth mentioning as a “beef”.

The first one is also a pretty bad argument when you look at evolution. The argument is that Wilson’s proposed solution would be inefficient, but it seems to me that one of the main thrusts of evolution is that it can indeed be — and often is — inefficient but as long as it works, that’s not a problem. When has it become a criteria for evolutionary explanations that it achieve maximal or even reasonable efficiency. To go down that route would risk re-introducing a need for a designer, to ensure that the mechanisms stayed efficient. That can’t be what Coyne wants. But, again, why is efficiency even a factor? Why would you sort evolutionary arguments by efficiency? Being more or less efficient isn’t a hallmark of evolutionary mechanisms, so if two mechanisms are proposed but one is more efficient than the other that says absolutely nothing about which one is more likely to be true.

That leaves us with the main complaint: cheaters. The main issue here is that there is an issue raised against the individual selection explanations of altruism as well, even kin and reciprocal altruism and it is … cheaters. Cheaters will benefit if they can get away with it, and so those individuals will prosper and those who are altruistic will be outstripped, and so altruism is not self-sustaining at the individual level. To get around this, the proponents of evolutionary explanations for altruism end up appealing to cheater detection mechanisms, where we have the ability to check up on and then punish or restrict cheaters. Of course, all cheater detection mechanisms are also available to group selection; it could be the case that you have group or social detection mechanisms through things like shared rituals that detect cheating or at least make it impossible. For example, it might be hard to steal the rabbit for yourself if you have a strong social impetus to always hunt together, and that hunting alone is just undesirable.

Additionally, it seems to me that group selection can actually get this without having to apply specific cheater detection mechanisms. After all, group selection would imply that the relevant competing entity is the group. Thus, if a group has a significant percentage of people who are altruistic, then it outperforms groups that don’t. Thus, if you have a group where this happens and where too large a percentage of the group are cheaters, then that group will cease to get those benefits and be outcompeted and presumably eventually exterminated by the groups where that does not happen. Thus, group selection here becomes self-sustaining; if you are above or at the magical percentage that means you benefit from being altruistic, you benefit over other groups as long as it stays there, but if it ever drops below that your group may well collapse and your individuals, then, all lose. Note that we would still see cheater detection mechanisms emerge because they are mechanisms that make the group stable and so less likely to fall below that percentage and collapse.

So, not only is it the case that their main complaint applies to their alternative, it seems that group selection might have an easier time solving that problem than individual selection does.

Now, of course both of these miss the main objection to evolutionary explanations, which is that they fall apart the instant you can start acting for reasons. While Coyne denies free will, he hasn’t quite eliminated us acting for conscious reasons yet, and surely I can decide in some sense of the word decide if I will co-operate or cheat, and I can do that on a case-by-case basis. Thus, once conscious reasons can override evolutionarily ingrained instincts, it becomes pointless to try to explain altruistic behaviour through unconscious evolutionary mechanisms or conscious consideration of advantage. The former is not what will be used and the latter is clearly no longer altruism.

At any rate, of the three objections given by Coyne none of them, when examined strictly, are all that strong an objection. Now, I’m not completely up-to-date in this sort of theory and so might well be missing something, but it seems to me that if Coyne wants to claim that Wilson has lost it, he should come up with arguments that are more obviously problematic than the ones he’s given here.

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One Response to “Wilson and Dawkins and Group Selection …”

  1. Group selection, again. Yay. « A Bit of Behavioral Ecology Says:

    [...] seem to figure out how to embed links to anything but his own blog in his posts) I came across a post by a blogger who calls him/herself “The Verbose Stoic”.  This piece is problematic on [...]

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