The cultural evolution of age-at-marriage norms

We present an agent-based model designed to study the cultural evolution of age-at-marriage norms. We review theoretical arguments and empirical evidence on the existence of norms proscribing marriage outside of an acceptable age interval. Using a definition of norms as constraints built in agents, we model the transmission of norms, and of mechanisms of intergenerational transmission of norms. Agents can marry each other only if they share part of the acceptable age interval. We perform several simulation experiments on the evolution across generations. In particular, we study the conditions under which norms persist in the long run, the impact of initial conditions, the role of random mutations, and the impact of social influence. Although the agent-based model we use is highly stylized, it gives important insights on the societal-level dynamics of life-course norms.