Some birds sing to attract a mate. Others dance or display colorful feathers. But in the moonlit forests and shrublands of northern Argentina, one bird courts romance by snapping its wrists together, producing a sharp clapping sound scientists have puzzled over for decades. Now, researchers have captured the behavior in detail for the first time, revealing how scissor-tailed nightjars create one of the most curious sounds in the avian world.

Some birds sing to attract a mate. Others dance or display colorful feathers. But in the moonlit forests and shrublands of northern Argentina, one bird courts romance by snapping…

These Odd Birds Flirt by Clapping in the Middle of the Night: Who needs love songs when you can snap your wrists together loudly?