Environmental variations promotes adaptation in artificial evolution

In this paper we analyze the role of environmental variations in the evolution of artificial agents situated in an external environment. By comparing the results of experiments carried out in different conditions we demonstrate how environmental variations promote the evolution of better solutions. The beneficial effect is maximized at intermediate rates of variations, i.e. when the dynamics of the environment displays a sufficient level of stability and variability. The advantage of intermediate rates of variation is due to the fact that the occurrence of new environmental conditions favors the retention of phenotypic variations that can eventually provide an advantage also in different environmental conditions. Moreover, a relative stability of the new environmental conditions constitutes a prerequisite for the generation and retention of such variations.