Abstract
A large body of research has investigated the advantages of combining phenotype adaptation and genotype adaptation. The hybridization of genetic search and local search methods, often known as memetic algorithms, and the influence of learning on evolution, i.e., the Baldwin effect and the Hiding effect, have been widely studied. However, most work assumes a stationary environment, and thus overlooks potentially advantages or disadvantages that can arise from phenotype plasticity only in changing environments. We show that a process with two levels of adaptation allows the system to operate on two different levels of diversity at the same time, which can be of great advantage under certain environmental conditions. © 2007 IEEE.