Abstract

Cultural traits are those phenotypic traits whose development depends on social learning. These include practices, skills, beliefs, desires, values, and artefacts. The distribution of cultural traits in the human species changes over time. But this is not enough to show that culture evolves. That depends on the mechanisms of change. In the cultural realm, one can often observe something similar to biology’s ‘descent with modification’: cultural traits are sometimes modified, their modifications are sometimes retained and passed on to others through social learning, until new modifications are added. In this way, new modifications are piled on top of old modifications, generating cumulative change. But, again, this is not enough to show that culture evolves. For culture to evolve, cumulative change must be the result of hidden-hand mechanisms similar to those that explain cumulative biological change. If cumulative cultural change cannot be explained in these terms, the analogy between cultural change and biological evolution is unhelpful. The best known biological mechanism is natural selection. There are reasons to think that cultural change is at least sometimes due to natural-selection-like mechanisms. The adaptive fit often found between cultural traits and the environment has in many cases been built gradually and in a way that involves natural selection operating at the cultural level. The parallel with morphological adaptation is compelling. No complete and universally accepted account of natural-selectionlike processes operating at the cultural level exists at this stage. But at least three kinds of processes seem possible.