With natural selection, grating noise becomes soothing sound
Musicians, take note: An artistic mind isn’t required to create appealing music. Starting with short sound sequences more grating than Muzak, scientists created pleasing tunes simply by letting them evolve through a Pandora-like process of voting thumbs up or thumbs down on each sequence.
Inspired in part by long-running experiments probing the evolution of bacteria, computational biologist Bob MacCallum and colleagues decided to see if pleasant music could evolve from a cacophonous mess when human listeners acted as the force of natural selection. The researchers started with a loop of simple audio wave forms and let it randomly evolve to generate a starter population with variation on which selection could act. Then more than 6,000 people listened to the audio loops and rated how much they liked the sounds on a five-point scale. The audio loops rated more favorably were allowed to mutate or combine with others to make a next-generation clip; the bad ones died off.