Curious Behavior: Yawning, Laughing, Hiccupping, and BeyondRobert Provine boldly goes where other scientists seldom tread in search of hiccups, coughs, yawns, sneezes, and other lowly, undignified human behaviors. Upon investigation, these instinctive acts bear the imprint of our evolutionary origins and can be uniquely valuable tools for understanding how the human brain works and what makes us different from other species. Many activities showcased in Curious Behavior are contagious, but none surpasses