The Royal Family

Co-evolutionary algorithms are able to simulate multiple species evolving in a shared environment. Previously, master tournaments have been employed to establish more accurate fitness measurements, in response to the Red Queen Effect. This study proposes to apply a taximetric cluster analysis to master tournament data. This allows to build a hierarchical ‘family’ tree, based on the phenotypes (i.e. behaviours) displayed during the master tournament. Using this approach, the study explores the following issues: First, co-evolution often shows cycling dynamics, which might be related to phenotypic plasticity, i.e. cycling might promote plasticity while plasticity might suppress cycling. Using the cluster analysis, this study shows that a cyclic phase in evolution might indeed be superseded by a plastic phase. Furthermore, it was demonstrated that the cluster analysis can be used in further formalizing previously established results, such as that plastic individuals are able to cope with multiple rigid individuals. Secondly, a state of pseudo-plasticity might be realized on a genetic level. This study proposes the existence of ‘switching genes’, which control the expression of dormant phenotypes. It is plausible such genes might play a role in cyclic phases of evolution as well, as they could enable a species to adapt quickly, without resorting to costly ontogenics. The study shows that cyclic phases are expectedly devoid of large genetic change. When randomly mutating families from these phases, it is possible this could trigger switching genes, causing a switch in opponent specialization. However, no such effect was clearly seen, possibly due to clouded data resulting from an indiscriminate mutation technique employed.