" If efficient copying is adaptive, such that natural selection should favor greater and greater reliance on social as opposed to asocial learning, then the tournament also establishes that a number of characteristics strongly evocative of human culture will follow automatically. With increasing copying inevitably comes greater behavioral diversity; the retention of cultural knowledge for long periods of time; conformity; and rapid turnover in behavior such as fads, fashions, and changes in technology. Provided copying errors or innovation introduce new behavioral variants, copying can simultaneously increase the knowledge base of a population and reduce the range of exploited behavior to a core of high-performance variants. Similar reasoning accounts for the observation that copying can lead to knowledge being retained over long periods of time, yet trigger rapid turnover in behavior. Low-level performance of suboptimal behavior is sufficient to retain large amounts of cultural knowledge in social learning populations, over long periods. A high level of copying increases the retention of cultural knowledge by several orders of magnitude. "

― , Darwin's Unfinished Symphony: How Culture Made the Human Mind