14 Weird Things That You Can Catch and Contagious
Yawning, laughing, itching, coughing, vomiting, and crying are all socially contagious. Yawning is so infectious, says psychologist Robert R. Provine, author of Curious Behavior, that we yawn when we see, hear, or even read about someone else doing it. “We are often herd animals, not in full conscious control of our behavior,” he says. Scientists theorize that sharing these quirks conferred an evolutionary advantage: Laughter is a form of bonding; scratching an itch, a safety precaution.