Tubular-dorsal nervous system of chordates

Question

Whether tubular-dorsal nervous system of chordates is associated with the radial or lateral symmetry? How does this explain the complexity level of nervous system achieved by the vertebrate evolutionary branch?

Answer 1

Tubular and dorsal nervous system of the chordates is correlated to cephalisation, within these animals and also to bilateral symmetry. Presence of the neural integrating centers along with concentration of neurons in brains and spinal cord permitted the increase of interaction complexity between these animals and the environment. Receptor (afferent conduction) and efferent (regulatory, motor and behavioural reactions) functions come out more sophisticated in chordates because of the presence of more well-built neural networks. These traits have been preserved through the evolution as they give the adaptive advantage to their owners.