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Results.

No speciation was observed in these experiments. Three of the runs (numbers 3, 5 and 9) exhibited Class 2 dynamics for their whole duration, and five of the others (numbers 2, 4, 6, 7 and 8) switched to Class 1 dynamics during the run.

The remaining run (Run 1) probably fits into Class 1 as well, although the results were slightly unusual. Systems showing Class 1 dynamics typically contain properly functioning self-replicating programs, but as these are unable to spread though the population, numbers of each type of program are low, and the population diversity is high. However, in Run 1 of this experiment, all programs capable of faithful replication were lost after only 20,000 time slices. The population survived, but was composed of programs which either reproduced unfaithfully, or not at all. The evolutionary potential of this run had therefore been destroyed.

Analysis of the three runs which remained in Class 2 dynamics for their whole duration revealed that the ancestor program 348AAAA was able to survive even in the low-energy region, and that evolution proceeded in the same way as usual, with a single dominant genotype at any given time, towards greater numbers of energy collection instructions within the copy loop.


next up previous contents
Next: Large Gradient Up: Small Gradient Previous: Small Gradient
Tim Taylor
1999-05-29