Saturday, March 12, 2011
Hair Allows Hearing
Scientists discovered that our hearing is because our ears have tiny tubelike motors that mechanically amplify sounds.
Hair cells in your ears have spiky hairs like molecular mohawks. When sound waves enter the ear these hairs vibrate, and your brain computes it as sound. But these hairs don't move like grass in the breeze. The electrical signals the hairs produce feed back on the system, causing the hairs to tilt even more - called the “flexoelectric effect."
Hair length in different species explains why animals like bats can detect such high frequency sounds.