CULTURAL VS. GENETIC EVOLUTION

Human evolution is unique, having developed to the utmost extent a new survival tool: culture. Culture is found in many other animals, but the enormous power of communication made possible by language is not found in any other organism. What do I mean by culture? I like one definition I found in Webster's International Dictionary that I will paraphrase succinctly: the ensemble of knowledge, including customs and technologies, transmitted and accumulated through the generations, that played and continue to play an essential role in the evolution of our behavior. The mechanism of evolution of anything that can be reproduced and transmitted, be it genes or ideas, is dominated by three factors, which were first understood and defined in the study of genetic evolution: mutation, natural selection, and chance (random genetic drift). Although the factors underlying cultural and genetic evolution are very different, the same or similar principles and models are useful in understanding both.

Mutation is transmissible change, of genes or DNA in genetic evolution, and of ideas or brain circuits in cultural evolution. The second and third factors have been loosely described in genetic evolution as survival of the fittest and survival of the luckiest. When we speak of cultural evolution it may seem superficially that natural selection is not involved, i.e., that it is not the environment around us that decides our fate but rather that we take our destiny into our own hands by accepting or rejecting ideas, customs, and habits.