HAIDERSHOFEN, AUSTRIA—A quartzite hammerstone found at the site of Lehberg in Austria could bear the handprint of an ancient human ancestor that lived 500,000 years ago. Lehberg has offered up Acheulean axes and a phallus-shaped item that's splattered in ochre, but the new find ties the activities of Homo erectus in Europe to the hand painting done by its descendants 450,000 years later in caves like Rouffignac. Stereoscopic light microscope imaging of the hammerstone showed an ochre outline that likely corresponds to the ball and thumb of an ancient right-handed hominin. The faint stain was likely left when the long extinct user held the stone while grinding ochre with water to make a paint.