Summary: Humans have vestigial ear muscles that once helped our ancestors focus on sounds. New research shows these muscles still activate when we strain to hear in noisy environments. Scientists used electromyography to measure auricular muscle activity in people listening to an audiobook with distracting background noise.

A mechanism that activates specific muscles in our ears is a leftover from our evolutionary past, back when our ancestors depended more on their hearing for survival.

Vestigial human ear muscles react to sounds even if the external ear does not move. This could be used to build better earing aids.

Evolution has largely deprived us of our ability to swivel our ears, but those vestigial muscles still activate when we listen intently, according to new research.