UCT CS Research Document Archive

The Relationship Between Evolvability and Robustness in the Evolution of Boolean Networks

Shorten, David and Geoff Nitschke (2016) The Relationship Between Evolvability and Robustness in the Evolution of Boolean Networks. In Proceedings 15th International Conference on the Synthesis and Simulation of Living Systems (ALIFE VX), pages 276-283, Cancun, Mexico.

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Abstract

Robustness and evolvability have traditionally been seen as conflicting properties of evolutionary systems, due to the fact that selection requires heritable variation on which to operate. Various recent studies have demonstrated that organisms evolving in environments fluctuating non-randomly become better at adapting to these fluctuations, that is, increase their evolvability. It has been suggested that this is due to the emergence of biases in the mutational neighborhoods of genotypes. This paper examines a potential consequence of these observations, that a large bias in certain areas of genotype space will lead to increased robustness in corresponding phenotypes. The evolution of boolean networks, which bear similarity to models of gene regulatory networks, is simulated in environments which fluctuate between task targets. It was found that an increase in evolvability is concomitant with the emergence of highly robust genotypes, where evolvability was defined as the population’s adaptability. Analysis of the genotype space elucidated that evolution finds regions containing robust genotypes coding for one of the target phenotypes, where these regions overlap or are situated in close proximity. Results indicate that genotype space topology impacts the relationship between robustness and evolvability, where the separation of robust regions coding for the various targets was detrimental to evolvability.

EPrint Type:Conference Paper
Subjects:I Computing Methodologies: I.6 SIMULATION AND MODELING
ID Code:1191
Deposited By:Nitschke, Geoff
Deposited On:23 November 2017