This Is Why Cats Always Land on Their Feet

Cats' gravity-defying pivots mid-fall just got a clear scientific explanation. Researchers at Japan's Yamaguchi University say the secret lies in a spine that doesn't bend the same way from front to back, allowing cats to twist in midair without violating the rules of physics. Their study, published in the Anatomical Record, focused on how felines pull off the so-called "air-righting reflex," in which a falling cat manages to reorient its body and land on its feet. This "seems to contradict the laws of physics ... because an object in midair shouldn't be able to turn without something to push against," per Phys.org.

Using both cat cadavers and high-speed video of two live cats dropped onto a cushion, the team found that a cat's upper, or thoracic, spine is remarkably twisty, able to rotate almost 50 degrees, while the lower, lumbar spine is comparatively rigid. That combination lets the front half of the body rotate first—head and forelegs swinging toward the ground—while the stiffer rear section acts like a stabilizing base, preventing the full body from spinning out of control, before it follows. The live cats in the study seemed to prefer twisting to the right in the air, though it's unclear why, per New Scientist. The study authors say the sequential rotation they documented not only solves a long-standing biomechanical puzzle but could guide treatment of spinal injuries, and inform the design of nimble robots.