Cultural Evolution and the Shaping of Cultural Diversity

Introduction This chapter focuses on the way that cultures change and how cultural diversity is created, maintained and lost. Human culture is the inevitable result of the way our species acquires its behavior. We are extremely social animals and an overwhelming proportion of our behavior is socially learned. The behavior of other animals is largely a product of innate evolved determinants of behavior combined with individual learning. They make quite modest use of social learning while we acquire a massive cultural repertoire from the people we associate with (Richerson & Boyd, 2005: Chapter 2). Expertise in exploiting our environment, values about what matters in life and even feelings about whom to trust and whom to hate are mostly " absorbed " from those around us. What's more, we are very adept at transmitting cultural information to others, sometimes through frank teaching but also through the constant social interaction characteristic of human life: mutual observation and casual conversation during which behaviors and beliefs are seen, described, evaluated and generally gossiped about. As Rogoff (2003) notes, in traditional cultures teaching is not like formal schoolwork or the school-like teaching seen in modern societies and families. Children learn by close observation followed by concrete participation in the activities of everyday life, gaining greater participation as they master more complex skills. Adults teach in the sense that they tolerate children's participation and lightly guide and structure children's learning experiences. Cultural diversity inevitably develops in the course of cultural transmission. Individuals are constantly misremembering and thus varying some piece of culture, as well as making more deliberate variations. Learners will often put their own personal twist on what they have been taught. Once such a new " cultural variant " exists, there will be a tendency for it to be preserved. A woman's children may pick up a variant she created and spread it among their friends at school. They might then pass it on to their families. If such cultural processes were all that were operating, cultural diversity would increase without bound. In fact, although cultural diversity is great, it is not boundless. Other social processes operate to select and winnow away less useful cultural variants. This results in members of the same culture and sub-culture sharing a large proportion of their cultural information. The sharing of cultural information allows groups of humans to interact and cooperate effectively so it is essential that some …