There's a theory of culture evolution now, which is really relatively sophisticated. Rob Boyd, Pete Richardson and Joe Henrik are the main leaders in this field. They say that so long as people are copying each other with imperfections, then you will get a form of sort of spontaneous evolution happening. You don't have to have very faithful replication of ideas for there to be an effective competition between ideas - some taking over from others.
Matt Ridley talks with EconTalk host Russ Roberts about his latest book, The Evolution of Everything. Ridley applies the lens of emergent order to a wide variety of phenomena including culture, morality, religion, commerce, innovation, and consciousness.