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PhilGoetz comments on Group selection update - Less Wrong
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Comments (58)
The cited article is about species selection - but this post claims to be about group selection.
As biologists often use the terms, group selection and species selection are quite different concepts.
The standard objection to group selection - which is that gene transfer due to between-group migration and recombination usually swamps the effect of between-group selection - doesn't apply to selection between species - because there is little or no gene transfer between species.
As a result, species selection isn't very controversial - compared to group selection.
Group selection has been demonstrated in the lab (Wade's flour beetles, etc) - but there is still some controversy over its significance in nature.
Yes, species are groups - but the actual area where there is a controversy is over selection between groups that are within sexual species. Selection between species is not relevant to this.
However, I agree that articles like this make EY look as though he has wandered into an unfamiliar area - which he doesn't know as much about as he thinks he does.
That may be so. If so, I am misusing the terminology. But if so, other people routinely use the objection to what you are calling "group selection" to rebut invocations of what you are calling "species selection".
Hmm - I am not sure I have encountered that. Many definitions of "species" are based on there being little or no gene flow between different species.
Both group selection and species selection face the issue of the fact that reproduction rates are slow - compared to individual reproduction rates - so individual level selection could eliminate much of the variation on which higher-level selection could act.
However, with species selection, we know that species do eventually diverge - so there is some variation left to work on.
With group selection there's less evidence of divergence between groups - and there's an additional problem - that occasional gene flow between groups acts to reduce between-group differences. The math[*] suggests around 1 migrant per-generation is enough to make most group selection pretty ineffective - and 1 migrant per-generation is low for most natural groups. These factors are mainly what makes group selection more controversial.