Figure 3: Evolutionary suicide caused by the evolution of female preferences for high-quality resources.
In the first 1,000 generations, male competitiveness evolves in the absence of female preferences (p=0) in a scenario with large variation in resource quality (Rlow=0.2, Rhigh=1.8). In contrast to the earlier simulations female productivity is limited (60 eggs per female), resulting to a pronounced decline in population size when male competitiveness gets too high (generations 580 and 780). From generation 1,000 onwards, female preferences can evolve, starting from a negative value (p=−5). As long as preferences stay negative, male competitiveness remains low, resulting in an ecologically favourable state where no resources are wasted for competitiveness. However, female preferences evolve to positive values; this induces the evolution of male competitiveness to very high levels, eventually causing population extinction.
