E.O. Wilson now places group selection above kin selection
The idea that group selection (or multilevel selection) could have any validity is sometimes dismissed in rather derogatory terms. It may therefore come as a surprise that one of the main "fathers" of ev psych, Edward O. Wilson, now theorizes that kin selection is NOT the why of the evolution of eusocial insects, as widely accepted, but rather group selection -- and the same seems to hold true for humans.
In an interview in the June 2006 Discover Magazine(pp. 58-61), Wilson says that one reason he now rejects the "standard theory" he helped develop is that there's very little evidence that ants and termites in the early stages of evolution could determine who's a brother, sister, cousin, etc. He says: "They're not acting to favor collateral kin. The new view that I'm proposing is that it was group selection all along, an idea first roughly formulated by Darwin."
The key to Wilson's new theory is the relatively recent recognition that genes can be plastic in their expression, in response to different environmental conditions.
"So consider a gene", he writes, "that has placticity such that in one setting an individual carrying that gene becomes reproductive. Maybe this individual was the ant or wasp that arrived first, maybe it was the biggest one, or maybe it was the one to just by accident start laying eggs first. The important thing is that the reproductive role can shift from one colony to next and from one generation to the next. The group forms, and some individuals by circumstance become workers. Their cooperative behavior and the division of labor confer superiority on that group, with that particular gene, over other groups. It could be as simple as that."
Wilson explains that altruism is normally discouraged due to the fitness advantages of individual survival and reproduction, but it could pay for individuals to subvert their own interests to those of a group if the group is able to defend and exploit a very valuable resource (such as a hollow stem that could be a nest site). And once ants and termites became "fully social" they went on to dominate the world.
As for humans, Wilson agrees with Darwin that our evolution was largely a matter of "tribe against tribe" -- which might explain the endemic warfare AND altruism in which humans have engaged since prehistory. "The genes that favor this type of group cohesion would also favor an innate sense of morality and group loyalty. It would explain how so often group or tribe loyalty overrides even family loyalty."
In an interview in the June 2006 Discover Magazine(pp. 58-61), Wilson says that one reason he now rejects the "standard theory" he helped develop is that there's very little evidence that ants and termites in the early stages of evolution could determine who's a brother, sister, cousin, etc. He says: "They're not acting to favor collateral kin. The new view that I'm proposing is that it was group selection all along, an idea first roughly formulated by Darwin."
The key to Wilson's new theory is the relatively recent recognition that genes can be plastic in their expression, in response to different environmental conditions.
"So consider a gene", he writes, "that has placticity such that in one setting an individual carrying that gene becomes reproductive. Maybe this individual was the ant or wasp that arrived first, maybe it was the biggest one, or maybe it was the one to just by accident start laying eggs first. The important thing is that the reproductive role can shift from one colony to next and from one generation to the next. The group forms, and some individuals by circumstance become workers. Their cooperative behavior and the division of labor confer superiority on that group, with that particular gene, over other groups. It could be as simple as that."
Wilson explains that altruism is normally discouraged due to the fitness advantages of individual survival and reproduction, but it could pay for individuals to subvert their own interests to those of a group if the group is able to defend and exploit a very valuable resource (such as a hollow stem that could be a nest site). And once ants and termites became "fully social" they went on to dominate the world.
As for humans, Wilson agrees with Darwin that our evolution was largely a matter of "tribe against tribe" -- which might explain the endemic warfare AND altruism in which humans have engaged since prehistory. "The genes that favor this type of group cohesion would also favor an innate sense of morality and group loyalty. It would explain how so often group or tribe loyalty overrides even family loyalty."
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