Estimating the Degree of Neutrality in Fitness Landscapes by the Nei´s Standard Genetic Distance - An Application to Evolutionary Robotics

In recent years, not only ruggedness but also neutrality has been recognized as an important feature of a fitness landscape for genetic search. As it has been reported that the evolutionary dynamics on a fitness landscape with neutrality is clearly different from the canonical explanations, ruggedness alone might be inadequate describing it. Another measure, i.e., neutrality is required. In this paper, we proposed the use of the Nei´s standard genetic distance, which originates from population genetics, for estimating the degree of neutrality in fitness landscapes after minor modifications. Several computer simulations were conducted with an evolutionary robotics problem in order to investigate the validity of the proposed approach. The results suggest to us that the Nei´s genetic distance is a reliable method for estimating the degree of neutrality on real-world problems.