We study natural selection of preferences using a golden-age model with endogenous population. In equilibrium, all agents have preferences with maximum biological fitness given resource constraints and total population is the maximum the environment can sustain. Naturally selected agents follow the golden rule, acting as if they maximize the undiscounted sum of per-capita felicities of current and future generations. Selected preferences and hence work, saving, consumption, and population density vary predictably with environmental differences.

The authors study natural selection of preferences using a golden-age model with endogenous population. In equilibrium, all agents have preferences with maximum biological fitness, given resource constraints, and total population is the maximum the environment can sustain. Naturally selected agents follow the golden rule, acting as if they maximize the undiscounted sum of per-capita felicities of current and future generations. Selected preferences and, hence, work, saving, consumption, and population density vary predictably with environmental differences. Copyright 1990 by American Economic Association.