Fig. 2. Cumulative culture simulation.

In our simulation, agents had to find successive innovations by combining virtual medicinal plants. They were given an initial set of six medicinal plants, which could be combined in triads to generate new drugs (A1, A2, A3, B1, B2, and B3) of increasing medicinal value. At the fourth level of innovation, a crossover of trajectories A and B produces the two medicines with highest efficiency (crossovers 1 and 2). The virtual experiment was finished when a crossover was found. Figure and simulation were adapted from (10).