Question

Is the tubular-dorsal nervous system of chordates associated with radial or lateral symmetry? How does that explain the level of nervous system complexity attained by the vertebrate evolutionary branch?

Answer 1

The tubular and dorsal nervous system of chordates is related to the cephalization in these animals and to bilateral symmetry.

The presence of neural integrating centers with a concentration of neurons in the brain and the spinal cord (central nervous system, CNS) permitted the increase in the complexity of the interaction between these animals and their environment.

Receptor (afferent conduction) and efferent (motor, regulatory and behavioral reactions) functions are more sophisticated in chordates due to the presence of more better-developed neural networks. These features have been preserved by evolution, as they provide an adaptive advantage to the species in which they are present.