Bass Booster

By coiling up like a snail shell, the human inner ear concentrates the energy of sound, increasing sensitivity in the bass range, researchers have found. In different mammals, the tightness of the coil affects the range of frequencies a species can hear.

The coiling of the cochlea — the fluid-filled structure of the inner ear that detects sound and turns it into nerve signals — guides sound the way a whispering gallery does, explains Daphne Manoussaki, a mathematician at Vanderbilt University in Nashville.