Humans aren’t alone when it comes to yawning — all vertebrates do it too, including fish, amphibians, reptiles, birds and mammals. But why? The “evolutionarily ancient” act of yawning likely serves a ...

After a hearty lunch at work, you and your co-workers go into a meeting. First one colleague starts to yawn, then a second and finally it’s your turn. Many biological explanations have been put ...