Everyone likes a good belly laugh from time to time, and science supports that feeling. Studies have shown that laughing is linked to our physical, emotional and mental well-being â even our relationships. Here are some things you might not know about laughter. Laughter was a survival tool Laughter is thought to have evolved as a form of social bonding in animals and as a way to express playful intention. Many mammals laugh when they are tickled and when they engage in physical play. But humans don't need a physical trigger to laugh â though generally we can't help but laugh if we're tickled.