The acoustic niche hypothesis.

Sounds in the jungle or forest are not a cacophony of cluttered noise but a lush musical harmony. 

Creatures evolved to make sounds in different rhythms and pitches so as not to interrupt each other. 

Many creatures need to hear and be heard in order to find food, water, mates. And it's best to do that without wasting energy.

So they evolved over millions of years to be able to all make sounds together but without interrupting each other. 

It's like evolution, brutal a rap as it gets, actually forged a sonic civility.

They're trying to find that niche [amongst the cacophony of sound] which is a clear channel of communication so that their voices can be heard.

Bernie Krause and Stuart Gage developed the acoustic niche hypothesis, posing that creatures sharing an ecosystem evolved to make sounds in different rhythms and pitches so they don't get in each other's way.

https://podcasts.google.com/?feed=aHR0cHM6Ly93d3cubnByLm9yZy9yc3MvcG9kY2FzdC5waHA_aWQ9NTEwMzA3&ep=14&episode=ZTA1YmU2YzMtYjQzYS00Yzk1LThkZDktMjkyNDRkN2QyMzYw&pe=1&pep=786493

Transcript at:

https://www.npr.org/transcripts/821648089

Contributed to Invisibilia 

by Abby Wendle