Can we resolve the ‘group selection debate’ by focusing on human cooperation?
Posted 12 Jun 2015 / 13ASEBL Journal “Morality and Selection – How?”
This is an interesting article that tries to frame the debate over multilevel selection. Lots of other people have tried to similarly frame this debate, and I am pretty sure that no single prescription is going to resolve the debate. There is a debate about whether we need multilevel selection to understand biological phenomena in large part because biological phenomena are so diverse. Different biologists in different realms have different perspectives on this ‘debate’ because multilevel selection is a valuable tool to particular degrees in their particular realms (sometimes totally necessary, sometimes totally unnecessary, hence the polarized debate).
What I like about this article is that it asks that we consider the human realm specifically, particularly from a bio-cultural (in other words, a gene-culture coevolutionary) perspective. I think that this is entirely appropriate, as human culture is its own completely different evolutionary phenomenon (other than being dependent on our biology, which has much in common with our closest animal relatives).
That said, this article’s call for resolving the debate by focusing on human cooperation seems a bit odd to me. I liken it to trying to resolve the debate which baseball team is the best of all time? from within the lobby of a particular team’s stadium. You cannot get a universal answer from within a particular context. Humans are interesting, and I would predict that looking at human cooperation might allow us to say at least one species has been shaped by group selection, but would that end the debate?
Maybe, but only because our ‘debate’ is so ridiculous. The real reason that there is anything that we might call a ‘group selection debate’ is because there is a large contingent of very orthodox evolutionary biologists — most of whom work in biological systems where multilevel selection is not important — who insist on clinging to the 1960’s idea that group selection can never work as an evolutionary mechanism. Isn’t it about time that we just ignore these fanatics?
This article also uses a short exploration of human moral emotions to argue that multilevel selection is necessary to understand the evolution of said emotions. I cannot agree more that looking at the proximate mechanisms underlying our behaviors — what humans call “emotions” — is critical to understanding what needs to be explained. And I also agree with Robert Axelrod’s original interpretation of the computer algorithms’ decision-making mechanisms: if those mechanisms were found in a human being, we would likely use words like compassion, indignation, and forgiveness to describe them. But arguing that these proximate drivers were shaped by levels of selection above the individual (or individual gene) simply using logic is not very scientific. It is ‘weak hypothesis testing’ at best. Basically Sloan is arguing in this piece that our moral emotions are easier to explain from a multilevel selection perspective. But to actually test the hypothesis that moral emotions allow us to succeed because they produce group-level benefits, we would have to go back to Darwin’s suggestion and actually show that groups of humans in which these emotions are more prominent drivers of behavior out-compete groups in which these emotions have less influence on behaviors. That such a test is difficult to perform is why we are still having a debate.
I do not mean to nitpick, but I have to point out a few things in this article that are just plain wrong:
- I don’t know why one would concede that all forms of genetically-coded altruism are best explained by gene selection. First there is the question of whether kin-level selection is best described as gene selection, but beyond that smaller question there looms the larger question is culture the only thing we can’t explain via gene-level selection? It seems pretty clear to me that there are a lot of altruistic phenomena in nature that have not been well-explained by simply appealing to selection at the level of the individual or gene.
- Although I agree that understanding the evolution of cancer can yield insights into cooperation, this has nothing to do with debates about the behavior of current-day multicellular organisms. What studying cancer allows us to better understand is how multicellular cooperation was achieved, which is likely to shed very little light on why animals perform altruistic behaviors.
- If David Axelrod had written The Evolution of Cooperation, or if its actual author (Robert Axelrod) had served as Senior Advisor to President Obama, this would be a very different country!
A Minor Post, Cooperation, Cultural Evolution, Ethics, Group Selection, Methods, Multilevel Selection, Social Norms, Web
Chris, thanks for your post commenting on my article on the ASEBL Journal website. Some further clarifications on my part may be useful – I am always looking for better ways to communicate what science can tell us about the origin and function of cooperation.
The oddness you refer to of “resolving the debate by focusing on human cooperation” was because the article was written as a rebuttal to an Edge essay by Steven Pinker. In that article, Pinker attempted to argue against multi-level selection by, in part, showing how human altruistic behavior could be explained using a gene-level selection perspective.
I see the main reason that the “group selection” debate continues is that group selection opponents commonly think much more is being claimed than actually is. I expect these opponents would agree that what goes on at the gene level cannot contradict biological evolution due to individual or group level selection (when they occur). This implies that gene, individual, and group level selection are just different perspectives, or different accounting schemes as DS Wilson puts it, for the same phenomena. So, “in theory” individual and group level selection perspectives can explain nothing that the gene level selection perspective cannot.
What group level selection perspective opponents commonly overlook, in my perspective, is that while the “in theory” utility of the gene level selection perspective is fine, “in practice” its utility is poor when dealing with cooperation adaptations which require groups. As Pinker illustrates, the gene level selection perspective leads even brilliant and knowledgeable investigators, such as himself, into error producing, “selfish gene” shaped mental traps.
Specifically, Pinker’s hypothesis is that human altruistic behavior is best explained as kin selection, self-interested ‘altruism’, and social pressure. However, Pinker’s hypothesis cannot be correct because it has such poor explanatory power for the biology underlying our moral sense, which is what motivates altruistic behavior. As I describe, his hypothesis has poor explanatory power for what specific emotions are produced by our moral sense and the circumstances that trigger them. In stark contrast, the hypothesis that naturally follows from the group selection perspective, that our moral sense was selected for because it motivated cooperation strategies (including kin altruism), has wonderful explanatory power for all our moral sense’s emotions and the circumstances that trigger them.
In summary, the utility of the multi-level selection perspective is “in practice”, not “in theory”. I am confident we could start from the gene level perspective and through tortuous, convoluted reasoning get to a correct hypothesis about the origins and function of our moral sense. But why struggle with that when the group level perspective leads to the apparently correct hypothesis so naturally because cooperation must occur in groups?
You said that to test my hypothesis about moral emotions “… we would have to go back to Darwin’s suggestion and actually show that groups of humans in which these emotions are more prominent drivers of behavior out-compete groups in which these emotions have less influence on behaviors.” But imagine we had one group composed of rational psychopaths who, nevertheless, were highly cooperative purely out of self-interest. They, who have large and perhaps complete deficits in their ability to experience moral emotions, could out-compete other groups with fully functional moral emotions and less cooperative cultures. Your test is about cooperation which is a broader phenomenon than moral emotions. I see it as much stronger science to rank the truth of Pinker’s hypothesis and my hypothesis as I did it, using standard ‘truth’ criteria such as explanatory power for our moral sense, no contradiction with known facts, simplicity, integration with the rest of science, and so forth.
Looking over your interesting site, I was pleased to see that, at least from my perspective, we have highly complementary approaches to understanding cooperation.