More than 420,000 years ago, in a cave in present-day Israel, a human ancestor removed the feathers from the wing of a swan—and researchers still don’t know why. A team of archaeologists examined bird bones found in Qesem Cave, a paleolithic site about 10 kilometers from Tel Aviv, Israel, and found cut marks (pictured) on the wing bone of a swan that could only have come from defeathering, the newspaper Haaretz reports. The humans were unlikely to be using the bone for food, as the swan’s wing was effectively meatless, the researchers report in the Journal of Human Evolution. Ancient people may have removed the feathers to wear as adornments, to decorate their living spaces, or to use in rituals, the researchers speculate, although this is far earlier than other examples of ritualistic behavior in human ancestors.
*Correction, 1 October, 12:35 p.m.: The dates in this story have been corrected.