Tuesday 13 May 2014

Goodnight on kin selection rampage

Charles Goodnight has been explaining why he doesn't like kin selection recently, in a string of articles - most notably Why I Don’t like Kin Selection.

However, this article seems littered with misunderstandings to me. Goodnight claims kin selection can only focus on altruism. That is a mistake - kin selection has also been applied to spiteful behaviour. Goodnight claims that kin selection can't handle cultural relatedness. That's wrong - cultural kin selection handles cultural relatedness just fine. Goodnight claims that kin selection is ¨an optimality approach¨. In fact, evolution is a gigantic optimization process. All adaptations are the result of optimizations. The accusation that that kin selection is an optimality approach just seems totally confused to me. Goodnight claims that multi-level selection models in which selection on different levels acts in the same direction can't be studied using kin selection models. That seems ridiculous to me - of course they can. In fact, neither group-selection nor kin selection models spend much time on this case. For group selection, this is because proponents are still struggling to find evidence for their effects - and this case typically doesn't help do that.

Goodnight winds up publicly explaining where he doesn't understand kin selection. That's fine - but readers should not be persuaded by an article with so many mistakes.

The article closes with:

However, like optimal foraging theory, it appears to mainly be useful in making broad stroke qualitative predictions that can be used in the introduction, or in a laudatory paragraph about how wonderful Hamilton is at the end of a paper. If you want to make quantitative statements about selection in real world populations that will contribute to our understanding of social evolution multilevel selection might be a better choice.

Ironically, this is almost the exact reverse of what kin selection enthusiasts often say about group selection. Kin selection features the coefficient of relatedness - whereas group selection is rarely concerned with the level of relatedness within or between groups. So: kin selection is typically quantitative, while group selection is much more concerned about identifying the level at which a feature is adaptive - which is a more qualitative issue.