I was amused to see that David Sloan Wilson took a weird poke at Dawkins, got thrashed by Jerry Coyne, and didn’t like it. In fact, I was going to leave this as a link post, but while searching for a link to Coyne’s piece (Wilson can’t 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 several points, but discussing this is going to take some space so I’ll do it here instead of a comment on Verbose Stoic’s blog; from here on, I’m going to refer to him/her as VS.
VS starts off by questioning “examples”:
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.
Look, Wilson isn’t citing any specific cases of group selection occurring in nature, mostly because there aren’t any. When I say that, I mean that Wilson hasn’t been able to demonstrate that a trait arose because of group selection and not kin selection or natural selection or any other evolutionary force. Wilson’s argument is that (1) group selection (a.k.a. “new” group selection or multi-level selection) is something different than any other variety of selection, and (2) that it is responsible for the evolution of traits such as altruism. But (1) group selection reduces mathematically to inclusive fitness (follow the links in my previous post), and so (2) is trivially true. Sure, it arose by “group selection”, but that’s an empty statement. Wilson’s ‘proposed example’ is a theoretical model that was dealt with when he proposed it nearly 40 years ago (Wilson, 1975), and though it’s been refuted dozens of times since, he keeps holding on to it and insisting that he’s already won. I’ll quote at length from West et al. (2007) to drive home the point:
It has since been shown that kin selection and new group selection are just different ways of conceptualizing the same evolutionary process. They are mathematically identical, and hence are both valid (Hamilton, 1975; Grafen, 1984; Wade, 1985; Frank, 1986a, 1998; Taylor, 1990; Queller, 1992; Bourke & Franks, 1995; Gardneret al., 2007). New group selection models show that cooperation is favoured when the response to between group selection outweighs the response to within-group selection, but it is straightforward to recover Hamilton’s rule from this. Both approaches tell us that increasing the group benefits and reducing the individual cost favours cooperation. Similarly, group selection tells us that cooperation is favoured if we increase the proportion of genetic variance that is between-group as opposed to within-group, but that is exactly equivalent to saying that the kin selection coefficient of relatedness is increased (Frank, 1995a). In all cases where both methods have been used to look at the same problem, they give identical results (Frank, 1986a; Bourke & Franks, 1995; Wenseleers et al., 2004; Gardner et al.,2007).
VS also isn’t happy about “efficiency”:
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 […]
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.
It seems like VS might be on the verge of confusing old and new school group selection, as the bolded statements (my emphasis) suggest. West et al.’s paper has a great figure that shows the difference between the two:
In the text of their article, they point out that “[a]nother way of looking at this is that the new group selection approach looks at the evolution of individual characters in a group structured population, whereas the old group selection approach looks at the evolution of group characters”. VS’s own words make him sound like a disciple of Wynne-Edwards, which would be unfortunate since Wynne-Edwards was decisively crushed by George Williams in the 1960s. But even if he’s just poorly recapitulating Wilson’s models, VS is still wrong on the evolution of altruism. There are a number of possible explanations for altruism, including inclusive fitness, but I don’t want to get into a long conversation on how altruism might have evolved because I would have research and then write an inconveniently long book to do so.
Having said that, Coyne’s use of “cheating” (even in quotations) is a little unfortunate, because it overlaps with the literature on Prisoner’s Dilemma and cooperation. Cooperation and altruism are not the same concept (again, see West et al. for a good breakdown of the different concepts, or any text on social evolution); altruism might be a subset of cooperation, depending on how you define the terms, but usually altruism comes at a cost to the altruist while cooperators do not necessarily pay a cost to cooperate. “Cheating detectors” is more appropriate for a conversation about cooperation than altruism (see also Figure 2 of this paper), which makes the rest of VS’s argument difficult to respond to. I think that Coyne is using ‘cheating’ to refer to individuals who receive the benefit of altruistic acts without paying the price of altruism, but that’s not the same as cheating in models of cooperation. (Honestly, ‘cheating’ isn’t a great word on a lot of grounds, including confusion with other areas such as signalling and an implication of conscious intent where none is necessary).
Returning to the posts that started this digression: my honest belief is that this group selection debate should have been over years ago, but I will still support Wilson’s right to continue trying to make his case. If he’s going to attack people like Dawkins and Coyne, though, he’d better learn to be prepared for them to hit back. And though it’s unlikely that either of them will ever read this post, I’d like to tell them that they’re not alone.
P.S. Can I take this opportunity to point out a further example of Wilson claiming that people agree with him when they don’t? If you read the end of Wilson’s second piece, he says:
For readers who are up for a challenge and want to learn more about the theoretical basis and empirical evidence for group selection from someone other than myself, I recommend Steven A. Frank’s “Natural Selection. III. Selection vs. Transmission and Levels of Selection (Journal of Evolutionary Biology, 2011). For Frank, it goes without saying that natural selection is a multilevel process and that the group level is often a significant evolutionary force.
I’ve actually read that paper. In it, Frank once again points out that kin selection and group selection are the same thing:
The equivalence of r and Hamilton’s formal theory of kin selection establishes the exact equivalence of multilevel group selection and kin selection.
And then, after a long analysis, he compares the usage of the two methods in a section entitled (tellingly): Reasons to favour kin selection over group selection. It contains exactly what the title says. If you can get it and you like technical discussions of evolutionary biology, I urge you to read the paper yourself. If you don’t, then just do me a favour and don’t accept Wilson’s claims about this paper at face value.
——–
A Bit of Behavioral Ecology 
“Unlikely that either of us will ever read this post?” Recalculate your probabilities. It was a great post, loaded with good points and explained very clearly. I learned a lot, and not just about DSW’s penchant for claiming support where it doesn’t exist.
Thanks for this!
–Jerry Coyne
Thanks! I’m glad you liked it. 🙂
egos and personalities aside (and I know there are plenty of both in this discussion), I’m not a big fan of the argument that group selection reduces to inclusive fitness mathematically – because if they do so, then there’s something fundamentally weird in the whole thing, given that they are conceptually very different. So I end up with the feeling that these models are describing pattern, and not process; as an (aspiring!) evolutionary biologist I am more curious about “why” than “how”. As a process, kin selection and multi-level selection are very different, relying in different assumptions and making fundamentally distinct causal predictions. The fact that they can both be explained by the same mathematical formulation tells me very little about the operating evolutionary forces.
I hope you don’t mind that I reply as a comment, even if it will be a bit long.
First, some preliminaries:
I haven’t read either Wilson or Dawkins on this in detail, and so admit that the arguments might be more fully developed in other works. I’m also not a biologist, and so will try to avoid disagreeing with the actual biology as much as possible.
I also do not come to either bury or praise Wilson. He may be right, or he may be wrong. I did fire a shot across all of their bows at the end of my post, but what I’m aiming at here is just examining these arguments as arguments, and the point of my post was that if they were trying to use these arguments to discredit group selection … well, I hoped they had better arguments. It’s an occupational hazard of doing philosophy [grin].
Finally, you are slightly mistaken in how you assess my ordering of arguments. I ordered them from weakest to strongest, and from minor to major. Therefore, the last argument is not, in fact, the “biggest mistake” Coyne makes; the first argument is, if we put aside the claim that evolutionary explanations like these can’t be used to explain volitional altruism, where we decide to act altruistic for reasons.
On the specific arguments, your reply to the first one I address seems, to me, to be basically that group selection, kin selection, individual selection, and everything like that are all parts of the same mechanism, and so it doesn’t make much sense to talk about group selection as being an alternative to inclusive or individual or kin selection. Putting aside the already raised problem that mathematical identity doesn’t always mean conceptual identity, I would first like to point out that it is not me who introduced that, but Wilson and Coyne, so if they’re wrong to say that they can be distinguished then of course my whole post doesn’t make sense, but only because they are looking at it wrong. I can shrug and move on. Second, in all of your sources and even in your post, you do keep talking as if we can still indeed say that a kin selection explanation — say — is to be preferred over a group selection one. If that’s the case, then my original point still stands, which is that you can’t use an argument that says that we have yet to find a case where group selection is the better explanation against a claim that in any specific case — altruism, here — group selection is the better explanation. Either he’s right that group selection is the better explanation here on paper, at this time, or he isn’t. If he is, that it has never been the better explanation before does not cast any significant doubt on that. If he isn’t, then you don’t need to muster that argument at all. So, presuming we can talk about which explanation is better, my point stands, it seems to me. And if we can’t, then it seems to me that Wilson might have reason to argue that recent work demonstrates that group selection is an important part of evolution for at least some traits, since it’s one part of the overall mechanism that we are now all lumping together into a suite of mechanisms.
On the second one, I actually am using efficiency the same way you are, although I admit it was not clear. It seems to me that evolution doesn’t select on efficiency at all, and so arguing that group selection is inefficient — the actual argument — doesn’t really mean much. You do seem to be implying that group selection is inefficient enough compared to the other types for this sort of thing so that if both are active group selection would be just getting started while the others were almost completed, and so it couldn’t be doing the bulk of the work. This isn’t a bad argument — and you can correct me if you mean something else — but it does presume that both mechanisms can be active and that group selection isn’t, in fact, the main mechanism that has to be used because the others have flaws. Again, if group selection is not the best explanation then we don’t need to use the efficiency argument, and if it is the efficiency argument doesn’t really do much against those other arguments. This one can impact which theory is actually the better explanation, but only in limited circumstances that I don’t think are the case here (but I might be wrong about that). But my main point was that calling an evoutionary theory inefficient either in how it works or how it got to that working mechanism means nothing unless you are appealing to the idea that maximal efficiency is an expectation of anything having to do with evolution, which I find … dubious, to say the least.
On the last one, I’m not really sure how this impacts my argument. My main argument is that appealing to cheaters — and we are using the term here the same way as well — is bad because all evolutionary theories of altruism that I’ve ever seen have been vulnerable to it as well, and I know that Dawkins’ version has been criticized for not being able to handle cheaters. All sorts of other mechanisms have been proposed to fix that, and I don’t see how group selection couldn’t use them as well. My example was just an example to show that selecting on the basis of groups might be able to work around that, and so as far as I can see it has nothing to do with new or old group theory. As long as you aren’t arguing that we always only have one grouping, you can still have groups that compete against each other, and so my loose, vague example that I don’t claim to be necessarily true can work. The only counter is to argue that under the new scheme all groups formed with “cheaters” would always become unstable and collapse, but I don’t see why that would be so and would also note that unless you clam that we didn’t form stable groups at all individual or kin selection would have the exact same issues, and so we’d still need an explanation of how to get stable groups from this if we have altruism at any level. But my main point was, again, that the objection from cheaters is one that as far as I can recall at least Dawkins’ theory was vulnerable to as well, and so without showing that group selection is more vulnernable it is a bad argument to say that it is vulnerable to an objection that your own argument is vulnerable to as well. In the actual literature, this distinction may be explained in more detail and so the case may be made, and so I might have jumped the gun on that one, but it is still something that needs to be watched out for.
Hey, VS, thanks for stopping by. I admit that I’m struggling to deal with what you’re writing, because you’ve injected yourself into the argument between Coyne and Wilson and I’m mostly replying to how you’re conceptualizing the biology and the state of the debate.
I guess that I was responding to the order that you replied to them? You said “Let me deal with the two minor ones before getting back to the main event.”, and then talked about examples and efficiency before getting to the “main complained: cheaters”. In any case, I’m sorry if I misrepresented your ordering.
I know that Wilson views it as being distinct from reading his work but I’m not sure what Coyne thinks, and as I said before I’d like to avoid putting words in his mouth.
Let me try to clarify here. Group selection and kin selection are indistinguishable, mathematically. So in that regard, saying that one explanation is “better” than the other is nonsensical because they are talking about the same evolutionary force. Where kin selection can be preferred is in ease of use for the scientist in question; as Frank points out in his paper and West discusses at length in the video I linked to previously, kin selection arguments are easier to construct and use, mathematically and biologically. Now, that is to some extent a matter of subjective biology so I won’t drag you into it (though I urge you to go look at these sources if you actually have an interest in the biological questions). But I stand by what I was saying: Wilson has never (in the opinion of multiple smart people, and then not-so-smart me) come up with a valid example of group selection explaining something that can’t be explained – and explained more easily – using kin selection.
You’re right, we don’t need the efficiency argument because the two processes are the same. That’s why I said “assuming that group selection is different from inclusive fitness (which it’s not)”.
Maybe I wasn’t clear on what I mean by efficiency in the relative evolutionary sense, so I’ll try again. If kin selection and group selection were independent mechanisms, and if they were acting separately on two populations of organisms all containing the same genotypes in exactly the same environment (practically impossible, but this is a thought experiment), then the rate at which an allele for some new trait spreads in one population could be compared to the rate at which it spreads in another and so we could say which is more “efficient”. Alternatively, you could compare whether a beneficial mutation can establish itself in a population at all, or what proportion of the attempts to establish itself are successful; there’s multiple ways that one could use the term, which is why I was unclear as to which one they were using in the bit you excerpted (and I’m glossing over about a thousand sub-arguments here). In this sense, it is perfectly reasonable to talk about maximal efficiency from an evolutionary force. Note that these are all relative comparisons: comparing selection coefficients, or invasibility, or any of half a dozen other things. I still think that you might be influenced by popular accounts of evolution which – rightly – point out that evolution is subject to absolute efficiency or teleology; it doesn’t matter if the evolutionary process takes a thousand years or a million to accomplish a task, this is irrelevant to the truth of evolution. As you said: “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.” There’s never a question of introducing a designer if we talk about the relative efficiency of evolutionary forces, but you might need one if you were talking about the absolute efficiency of the evolution as a whole compared to our ability to think of faster or better ways for it to happen.
Finally, about cheating:
We’re really not. Let’s go back to the tapes. You said:
And then:
The way you describe the “main complaint” is that individual-level selection requires ‘cheater detection mechanisms’ to evolve altruism (where are you getting this, incidentally? I’ve love to see your source for that), and that group selection doesn’t need them. This is you’ve brought to the table and what I’m responding to. In response, I would say that you’re using ‘cheating’ and ‘cheating-detection’ inappropriately, and no such mechanism is needed for the evolution of altruism. The way you’re using cheating is appropriate for a discussion on the evolution of cooperation (of which the unfortunately-named ‘reciprocal altruism’ is a variety), but not altruism wherein an individual unconditionally sacrifices their direct fitness for the benefit of others. Note that I’m using West et al.’s definitions here, which I adopt because they go to great pains to untangle the semantic confusion around these terms.
There’s no such thing as a ‘cheater-detector’ in a system with altruism in it; non-altruistic individuals aren’t ‘cheating’ in a way that requires detection, because they’re not giving false information about their actions like you might find in a signalling system (pretending to be dominant, for example) or benefiting from another individual’s cooperation without reciprocating direct fitness benefits to the focal individual. That’s why I was critiquing the use of the term in my post. The evolution of altruism depends on whether the individual under selection gets enough indirect fitness benefits (whether you conceptualise that as group benefits or kin benefits is irrelevant) from sacrificing their direct fitness to allow for altruism to spread as a behaviour. Coyne and others use the term ‘cheaters’ to mean (I believe) ‘non-altruistic individuals who receive the fitness benefits of the sacrifice made by altruistic individuals without sacrificing themselves’, but I would prefer a term like ‘free-rider’ or ‘selfish individual’. The reason I prefer not using ‘cheating’ for this is because cheating has a specific term in other areas such as cooperation or signalling. In signalling, it usually means giving a signal that implies you are of one state (e.g. ‘strong’) when you’re actually in another state (‘weak’) in an attempt to benefit. In cooperation, cheating often refers to things like the technical meaning in the Prisoner’s Dilemma, where your opponent cooperates but you defect and gain the benefit from doing so. Whether you accept my argument about the terms or not doesn’t matter, though, because there’s still no need for detection of cheaters in an altruistic system. Worker bees that sacrifice themselves altruistically don’t need to detect that other bees didn’t; that’s not a part of how the system evolves. Here’s another more recent reference from West et al., wherein Figure 2 provides a clear summary of why ‘cheating detection’ isn’t relevant to altruism; because altruistic individuals receive no direct fitness benefits, mechanisms like detection, policing, reward/punishment, etc. don’t affect the spread of the trait.
Note that just to confuse the matter the flip-side altruism detection (kin discrimination, greenbeards) is a valid way to enhance the fitness of altruistic genes but are subject to cheating.
In truth, I’m not sure if the argument over Dawkins’ ideas on the problems of group selection as Wilson / Coyne are disputing is about old or new group selection (it’s a little unclear from context, and I don’t care to dig deep enough to figure it out). Again, though, I don’t want to get into a long discussion about how altruism does evolve. That’s a big topic and not suitable for this venue. I’m just responding to how you’re viewing the argument.
If I recall correctly Dawkins used kin selection / inclusive fitness to explain altruism in The Selfish Gene (and it was certainly used to explain it later), so no, his theory wasn’t “vulnerable” to it. In general new group selection isn’t vulnerable to it either, because it’s the same as kin selection. Old group selection is vulnerable to selfish individuals invading altruistic groups. As I mentioned above, I’m not sure what version they’re arguing about. In the end, I’m not trying to claim that altruism is a solved problem; there’s plenty of work left to do. What I’m saying is that old group selection doesn’t explain it and new group selection provides no additional explanatory power and often just gets in the way.
Well, I think there’s no real major disagreement left except the last one, and I think the problem is this: up until at least “The God Delusion”, Dawkins was suggesting that reciprocal altruism was indeed an explanation for at least a form of altruism, and reciprocal altruism is indeed vulnerable to “cheaters” (I use the term the way you claim Coyne uses it, BTW). In the critique of that book that I started and never finished, I called that out as an egregious error for similar reasons to yours:
“3) Reciprocal altruism …
… isn’t. Altruism, that is.
Throughout the chapter on “The Roots of Morality”, Dawkins is trying to justify the major “altruisms” as being derivable from his view of Darwinian natural selection. He tosses this out as one of the altruisms that can be explained by it. He describes it himself as “You scratch my back, I’ll scratch yours” [pg 247] and says it’s a “ … main type of altruism that we have a well-worked-out Darwinian rationale [for] … “ [pg 247]. The problem is that this isn’t a form of altruism at all.”
So, if that sort of altruism isn’t meant to be an altruism at all, but a notion of co-operation, then I don’t have quite so many issues with it. But throughout both that book and some coursework done on it, I’ve seen it used that way, and so it has issues. Perhaps kin selection has indeed supplanted it; I’m admittedly not up-to-date on the latest in it mostly because those methods don’t seem capable of addressing reasoned altruism as opposed to simply instinctive altruism.
So, if this is indeed a type of altruism and Dawkins really is using these sort of mechanisms to explain actual altruism, I think you pretty much agreed that my use is not unreasonable. If, instead, he’s using it to talk more about something like co-operation, then my use would be inaccurate, but it isn’t clear that Dawkins is not, in fact, using it in the first sense.
I might look at the sources, though, if I get the time. But I have lots and lots of things to do and read that interest me more. So much knowledge, so little time (and brain) [grin].
You’re right, reciprocal altruism is indeed vulnerable to cheating and as far as I can see, Dawkins uses it that way; I dug out my copy of The Selfish Gene and had a quick look through. Chapter 10 discusses the susceptibility of reciprocal altruism to cheating, while in the first chapter he even properly defines altruism itself: “Before going any further, we need a definition. An entity, such as a baboon, is said to be altruistic if it behaves in such a way as to increase another such entity’s welfare at the expense of its own”. The problem is that, as far as I can see, he doesn’t clearly distinguish ‘reciprocal altruism’ from actual altruism even though I think he gets it.
Yup, that sort of ‘altruism’ isn’t actually altruism at all, and the usage of the term ‘reciprocal altruism’ is really confusing. I wouldn’t be surprised if you’ve seen examples of it, because I know I have; sometimes in biology, more often outside. Here’s West et al., one final time to clear this up:
Re: sources…
I hope that you do get the time, especially if these issues interest you like they seem to. Dawkins is a great writer and The Selfish Gene is a great book, but as well as it holds up, the fact is that it’s 36 years old now and we’ve moved forward since then. There’s plenty of great new stuff to read. 🙂