There are many kinds of laughter. People may guffaw at a joke. They may giggle nervously in an uncomfortable situation. They may chuckle with mild amusement. They may snicker to express contempt — especially movie villains.
But while laughing seems uniquely human, it is not. Our closest evolutionary relatives do it too. Researchers now have compared laughter in humans to laughter in the various great apes — chimpanzees, bonobos, gorillas
