Transcript: Animal Hearing

NARRATOR: Most mammals and birds rely on their eyes to sense their world. But for some, hearing is the most vital sense for survival. It enables this hare to escape the lynx... And leads this desert fox to a meal. (cricket chirping)

Sounds are vibrations that travel like waves in the air around us, pushing air molecules. The stronger, or more intense, the vibration, the louder the sound (chirping rises in pitch). The faster the vibrations, the higher pitched the sound.

Some creatures can sense the exact location of sound, not just its pitch and volume. A barn owl has one ear hole slightly higher than the other. Its brain measures left and right by how long a sound takes to reach each ear. It measures up and down by how loud the sound is. From sound alone, the owl can create a map and hear where its food is, even in darkness.