Rainforest are well known for being hubs of biodiversity. In other words, if you're looking for mucho creatures—both in terms of numbers and species variety—this is the place where you want to be.
It's one of the biggest reasons why activists are so keen on keeping these habitats safe and healthy. But how do you actually know that a rainforest is doing well? By how it looks?
That seems like a good place to start. After all, there's certainly an easily noticed difference between a lush, green collection of trees and scattered growth. But even with so many resident animals, rainforests are so dense that the creatures can easily remain hidden. This is why many scientists are turning to how a rainforest sounds as a gauge of its health.
Layers of sounds
According to a paper published in Science journal, scientists are setting up recorders in rainforest as a way of figuring out which animals live there. It's like putting a stethoscope to a person's heart.
Have a listen to some rainforest sounds from a protected forest in Indonesia posted recently by Mashable.
What did you hear? Perhaps a repeating high chirping call? A bit of a hazy buzzing underneath it all? Try listening again through headphones this time. Do you hear anything else?
In truth, what you're listening to is dozens of creatures simultaneously lending their voices to the larger orchestra of rainforest sounds. Since rainforests are so dense with plant life, sounds are a major way that species communicate with each other. (If you can't see me, I'll make sure you hear me!) The animals even adapt their calls to find their own pitch so that they don't sing over each other—kind of like picking their own lanes on a sonic highway!
The result? The more you listen to these kinds of recordings, the more scientists notice when expected calls are missing. From insects to birds, primates to frogs, the absence of a call can be the first clue as to whether a rainforest might be in need of some TLC.
Let's listen in on another rainforest in Papua New Guinea. We hear new sounds every time we listen! What jump out to you?