Figure 1

Model of neural networks and environmental challenge. All networks were evolved under an asexual mutation-selection-drift process. Fitness of an individual network was obtained by providing an input gradient and retrieving from the network a response that was then matched to a response function or environmental challenge. Networks varied in their number of nodes and connections and the weight of each connection and nodes could be mutated to generate heritable variation. Response functions were described by Legendre Polynomials. A higher Order of the Legendre Polynomial reflected a more intense environmental challenge. Populations of networks with identical size were adapted independently to each of the environmental challenges.