Planetary Rotation and the Evolutionary Purpose of Nervous Systems

This preprint presents a timing-first theory of nervous system evolution. It reframes nervous systems not as information-processing or decision-making devices, but as biological timing-regulation infrastructures whose primary function is to preserve regulatory solvency: the capacity to complete repeated action–recovery cycles without accumulating unrecoverable timing debt. The paper identifies planetary rotation as a stable, inescapable source of periodic forcing acting on all matter through multiple physical channels (photonic, thermal, gravitational–tidal, chemical, and electromagnetic). These forcings impose non-negotiable constraints on energy availability, repair kinetics, and phase alignment. Nervous systems are shown to have evolved to govern timing and inhibition under these constraints, prior to and independent of sensing or cognition. This work provides a unifying evolutionary framework linking chronobiology, systems neuroscience, and biological regulation, and establishes timing governance as the prerequisite for admissible sensing, action, and cognition. It is intended as a foundational theoretical contribution and is shared as a preprint to establish priority and invite scholarly engagement.