  Evolutionary robot systems are usually affected by the properties of the
environment indirectly through selection. In this paper, we present and
investigate a system where the environment also has a direct effect: through
regulation. We propose a novel robot encoding method where a genotype encodes
multiple possible phenotypes, and the incarnation of a robot depends on the
environmental conditions taking place in a determined moment of its life. This
means that the morphology, controller, and behavior of a robot can change
according to the environment. Importantly, this process of development can
happen at any moment of a robot lifetime, according to its experienced
environmental stimuli. We provide an empirical proof-of-concept, and the
analysis of the experimental results shows that Plasticoding improves
adaptation (task performance) while leading to different evolved morphologies,
controllers, and behaviour.
