Llamas communicate with a variety of sounds. What does this sound like to a human’s ear?

The llama is a large camelid that originated in North America about 40 million years ago, and are widely used as meat and pack animals.

Llamas communicate with a variety of sounds. To a human’s ear, this sounds like humming. The hum has been likened to a cat's purr or sometimes to a person humming. Llamas hum when they are tired, distraught, curious, or worried. (They also spit when they’re angry, so think twice before you upset a llama just to hear it hum.)