Summary of Results

The summarise the results of this run, the programs are evolving towards increased A-longevity (Figure 5.7), but in doing so their A-fecundity decreases (i.e. their replication period increases: Figure 5.4). The programs do not evolve along the A-fidelity axis (Figures 5.6, 5.11, 5.12). The predominant evolutionary innovation is the accumulation of extra energy collection instructions within the programs' copy loops, which increases a program's chances of survival relative to its competitors (Section 5.2.7). No multicellular (parallel) programs evolved, nor did any parasites or any other sort of program that used code from neighbouring programs (Section 5.2.8). In other words, the evolution observed in this run was steady microevolution, with no spectacular macroevolutionary innovation. Analysis of the activity measures reveals that this run exhibits Class 2 dynamics, according to Bedau et al.'s classification scheme, which groups it together with various other artificial life platforms, and distinct from the evolutionary dynamics of the biosphere (Section 5.2.6). Reconstruction of the phylogenetic tree of the significant genotypes reveals that chance events may play a major role in determining the outcome of such a run (Section 5.2.7). We will look into this issue in detail in the next chapter.