excerpt from an edge original essay:
natural selection could legitimately apply to groups if they met certain conditions: the groups made copies of themselves by budding or fissioning, the descendant groups faithfully reproduced traits of the parent group (which cannot be reduced to the traits of their individual members), except for mutations that were blind to their costs and benefits to the group; and groups competed with one another for representation in a meta-population of groups.
but everyone agrees that this is not what happens in so-called “group selection.” in every case I’ve seen, the three components that make natural selection so indispensable are absent:
- the criterion of success is not the number of copies in a finite population (in this case, the meta-population of groups), but some analogue of success like size, influence, wealth, power, longevity, territory, or preeminence. an example would be the “success” of monotheistic religions. no one claims that monotheistic religions are more fission-prone than polytheistic ones, and that as a consequence there are numerically more monotheistic belief systems among the thousands found on earth. rather, the “success” consists of monotheistic religions having more people, territory, wealth, might, and influence. these are impressive to a human observer, but they are not what selection, literally interpreted, brings about
- the mutations are not random. conquerors, leaders, elites, visionaries, social entrepreneurs, and other innovators use their highly nonrandom brains to figure out tactics and institutions and norms and beliefs that are intelligently designed in response to a felt need (for example, to get their group to predominate over their rivals)
- the “success” applies to the entity itself, not to an entity at the end of a chain of descendants. it was the Roman Empire that took over most of the ancient world, not a group that splintered off from a group that splintered off from a group that splintered off from the Roman Empire, each baby Roman Empire very much like the parent Roman Empire except for a few random alterations, and the branch of progeny empires eventually outnumbering the others
…what all this means is that so-called group selection, as it is invoked by many of its advocates, is not a precise implementation of the theory of natural selection, as it is, say, in genetic algorithms or artificial life simulations. instead it is a loose metaphor, more like the struggle among kinds of tires or telephones.