Ever catch yourself yawning just by reading about it? That’s no coincidence: yawning—stretching your jaw wide, inhaling deeply, then exhaling—is an ancient behavior shared by vertebrates, from fish and birds to mammals. It even occurs in human fetuses before birth!
More than a simple reflex, yawning is fascinating for its contagious nature: just thinking about or seeing someone yawn can trigger one yourself. This seemingly simple act reveals surprising links between biology, behavior, and social bonding in animals and humans alike.
But what does science really say about yawning, and what does it mean for us? Click on to find out.