Travel back a century or so, to a chilly winter night. Christmas has come and gone, and New Year’s Eve is on the horizon when a group of carolers approach your door. They’re dressed as figures from the Nativity. Elated, you welcome them. Then you notice a terrifying stranger among them: a tall creature with musky-smelling hair, silver bull horns, and a snapping jaw pierced with nails. He dances and jumps to the music, sometimes pouncing on children. Meet Turoń, a symbol of virility. Polish Academy of Sciences folklorist Ewa…