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6 Conclusions
In Phase One, several fitness
functions were used to evolve images demonstrating suggestive
principles. In nearly all cases, successful evolution was achieved
quickly, generating images recovering some of the complexity of
two-dimensional CAs.
In Phase Two, the Bluenome
model was applied to a non-trivial artificial problem, one which
involved the coordination of many non-linearly interacting components.
In cases of low phenotypic complexity, the bijective methodology tended
to outperform the Bluenome method, with a wide margin in initial
generations, barely so in later generations. In cases of high phenotypic
complexity, however, one of the Bluenome runs clearly outperformed all
of the bijective runs, with a second matching with potential for further
growth in later generations. The Bluenome methodology continued to
develop in a high-dimensional space, while the bijective methodology
stagnated early on.
In addition to this
performance increase in high complexity runs, the Bluenome model showed
an inherent ability to generate agents with better developed systems for
the distribution of food throughout the body - this is no doubt a result
of the inheritance of cell specialization creating a network of
transport cells; Perhaps it is an easily identified example of one of
many inherent structural properties created by the developmental
process. It is unknown what other such mechanisms might exist.
Finally, the resistance of the developmental process to changes in the
environment was demonstrated - this is an intriguing notion, that an
agent's development should respond to the developing environment and
adapt. More intriguing still is the continuation of performance by the
re-developed agents, both in terms of valuation by the fitness function
in question, and in visual appearance.
7 Future Directions
The
artificial problem used in Phase Two was a difficult problem; That, and
other similar problems might be sufficient to convince practitioners of
the utility of this system. However, to evaluate claims regarding the
utility of developmental models in general requires a more in-depth
study. A study of the inherent structure created by developmental
processes in general is in order; This is our current interest,
initially by attempting to objectively measure the notion of continuity
between genotype and phenotype.
A second matter touched
upon in the above discussions is the view of evolution as a mechanism
for controlling complex processes; Indeed, this is an intriguing
hypothesis, perhaps contributing to the success of the above system; If
true, however, it begs an obvious question: by what mechanism? It is the
hope of the authors that systems like Bluenome may serve as a test bed
by which this claim may be evaluated and studied further.
References
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