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Evolution and Entropy

Independently of these studies, a series of runs was conducted using the original program with the original instruction set, and applying a tool for the calculation of entropy and its changes over time in an evolving ecological community. The entropy measure is negative sum of p log p, where p is the proportion of the community occupied by each genotype. For the purposes of this study a filter was used, which ignored all genotypes represented by a single individual. The purpose of the filter was to eliminate all mutants which were never able to reproduce (thus reducing the sensitivity of the measure to mutation rate). In addition, this entropy data was calculated for every birth and death, and then averaged over each million CPU cycle period. Only the averages over each period were recorded.

Thomas S.Ray
Thu Aug 3 13:06:00 JST 1995