Evolving functional symmetry in a three dimensional model of an elongated organism

In evolutionary-developmental biology, it is well established that neural organization is coupled to a given organism's body-plan. Many theories attempt to underpin this coupling and the transitions involved during the organism's evolution, for example the transition from radial to bilateral symmetry. Before theoretically tackling these transitions however, we felt it essential to first address, in this paper, precisely why bilateral symmetry might be advantageous for a simple eel-like agent. We find that neural architectures affording the best motor-coordinated behavior (architectures that allow directional swimming of the agent), will readily emerge in a way that is functionally-bilaterally symmetric, suggesting therefore, that bilaterally symmetrical emergence for a long elongated creature can be essential if it needs to travel over some distance. © 2007 alifexi.org.