Photo by Abhay Kewat
Collared Owlet in India
This is Asia's smallest owl at around 6.25 in /16 cm.
I've seen comments that it calls in all directions, making it a difficult owl to locate by sounds. Here is a video of it hooting all around. It's a pretty cute sound.
I did a little looking into it, and I think this would make a good post since it's a bit complicated, so it would make a good Owl-natomy post, which I haven't done in a while.
Bird have a very wild respiratory system due to their energy requirements, so they have very different parts than we do. Short answer is they have tremendous air reserves beyond just their lungs, and their version of a voice box is set much deeper in the chest than ours.
Also due to natural selection, since they use their voice to defend territory and attract a mate since they are solitary animals, louder voices will increase their ability to do both those things.
it's definitely interesting, I may have just done a web crawl that started with wikipedia references....
Nice, I like your initiative!
Wikipedia rabbit holes are always fun to go down, lol.