Cats have a unique and remarkable ability known as the "righting reflex" which allows them to reorient their bodies in mid-air to land on their feet. This ability is due to their flexible spine and a vestibular system in their inner ear that helps them maintain balance and a keen sense of orientation. Additionally, cats have a highly developed sense of proprioception, which allows them to sense the position and movement of their body in space, aiding them in landing on their feet when falling.