Archive: https://archive.today/2nZxt From the post: >>To test whether humans still use auricular muscles — which once helped move our primate ancestors’ ears to funnel sound — scientists attached electrodes to the sides of people’s heads, and asked them to listen closely to an audiobook. Different challenge modes were imposed, with the sound coming from different angles, and other competing sounds. The scientists found that, the more difficult it was for participants to hear the audiobook, the more the superior auricular muscles activated, as if participants were trying to prick up their ears like a dog or cat. When sounds came from behind a participant, the posterior auricular muscles contracted as if attempting to point the ears in that direction.