That sound you’re hearing is the haunting music of the Divje Babe flute, which many experts consider to be one of the oldest known instruments on Earth. Dating back to a Slovenian cave some 43,000 years ago, the flute is crafted from a cave bear femur. (Unless it’s just teeth marks from a hungry cave bear murderer, as other archaeologists suggest.) Listening to its spooky tune, I accidentally unlocked an ancient curse, and tumbled down a rabbit hole about the origins of music. While little is known about why we sing, scat, or play the tuba, one thing's for sure: humans love turning bones into flutes.