If genetic programming is considered as a stochastic hill-climber using a procedural representation, the role of the population is to provide genetic material in a more elitist algorithm. If genetic programming is to use the population to sufficiently explore the landscape in parallel, one needs to explicitly maintain portions of the population in beneficial areas and dispense sufficient search effort appropriately. The proposed niche for island models is an obvious extension to the research presented here and gives the population a much clearer role during search. Empirical studies, some of which were described in detail in Chapter 7, need to be carried out to validate the proposed island model.
Chapter 7 also introduced the Tree-String problem. Investigating the tunable nature of this problem would validate it as a future testbed for understanding complex domains. Future work can begin by modifying the size of the string symbol set and the method to grow target tree structures.