Fish have no necks, yet this ancient balancing trick keeps their heads startlingly steady in motion

Postural control is a fundamental behavior for most animals, and head stability in particular plays a crucial role in achieving stable sensory input, accurate spatial perception, and efficient motor output. Tetrapods, including humans, possess a "neck"—a structure that separates the skull from the trunk skeleton—and stabilize their head in space by contracting and relaxing neck muscles in response