Via my dear old friend, the brilliant microtonal composer/instrument builder Kraig Grady, comes this clip about the amazing yodel singing of the Central African pygmies. After getting all excited by this moving and beautiful music I hunted down the other couple of clips for my and your further aesthetic excitement. Incredibly lovely stuff.
 

 
Bayaka: The Extraordinary Music of the Babenzele Pygmies and Sounds of Their Forest Home