Memes revisited

In this paper, I argue that the adaptive fit between human cultures and their environment is persuasive evidence that some form of evolutionary mechanism has been important in driving human cultural change. I distinguish three mechanisms of cultural evolution: niche construction leading to cultural group selection; the vertical flow of cultural information from parents to their children, and the replication and spread of memes. I further argue that both cultural group selection and the vertical flow of cultural information have been important. More conjecturally, I identify a potential role for meme-based cultural evolution in the explanation of the 'human revolution' of the last 100 000 or so years, and defuse an important objection to that explanation.