system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can our ears know if a sound is coming from up high or down low?
gpt
Our ears are an odd shape, so the sound bounces around differently, depending on where the sound is coming from. 

When you're very young, your brain figures out that if a sound sounds a certain way, it's probably coming from a certain direction.