This model simulates the use of a renewable resource by agents and the evolution of the resource user population in the world. In the population, there are two traits with two variations each – Harvest behavior (sustainable, greedy) and the ability (or not) to perceive and punish other agents. Punishing agents have the ability to perceive other agents in their environment to a certain extent and to respond to their behavior. There are three possible types of reactions: they can kill agents with greedy harvest behavior, they withhold the ability of the agent to harvest any resources in the next iteration, or they make agents pay a penalty that is then distributed to its neighbors. Agents must pay costs (energy) both for perception and for the punishment, so this behavior is altruistic. Punishing agents have the ability to coordinate the punishment with a minimum number of punishers in order to share the cost of punishment.

Through this social behavior in the population greedy harvest behavior can become less advantageous or even disadvantageous and sustainable harvest behavior may spread in the population. In general, research shows that monitoring of behaviors and correcting feedback (such as through sanctions) are important mechanisms that allow groups to cooperate and sustainably manage common-pool resources, in human groups as well as in many other species.

The lesson plan contains a variety of activities using the model. You can skip certain phases depending on learning goals, student prior knowledge and interests, and available time.