| Cultural traditions (including languages) are transmitted across generations through learning by individuals in interaction with other members of the social groups to which they belong. Such groups are analogous to biological demes whose genetic heritage is transmitted across generations by the procreative interactions of their members. Cultural traditions and human biological demes coevolve like symbionts in mutual interdependency. There are many parallel processes, outlined here, in biological and cultural evolution. Basic in the content of cultures are understandings about the conduct of activities as the units of coordinated purposeful social behavior that provide the contexts for the emergence, maintenance, and modification of cultural traditions. Students of culture have yet to set necessary standards for controlled, systematic ethnographic research of a kind that will provide the database needed for a developed theory of cultural evolution. |