system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: To demonstrate the sensitivity of owls' hearing ability, we've been told that owls can hear mice running from hundreds of feet away. How do other sounds not muddle with the sounds of the footsteps?

If someone combined the voice of my friend with hundreds of other voices, it would sound like a glob of noise. How does this not happen with owls. Surely leaves rubbing together make the same amount noise as mice running, so there must be a lot of interference. How do they separate the different kinds of noise?
gpt
Different frequencies, mostly.

Ears are physically tuned to certain frequencies.  In an owl, it's the higher frequencies -- the frequencies little mice make.  They literally hear them "louder" than other frequency sounds.

The brain also has a way of mentally tuning in/out sounds.  (Ever heard your name called in a crowded room despite hundreds of other voices?)