Scientists aren’t totally sure, but here are a few ideas:

Self-defense 🛡️

Some of our most ticklish spots (like your armpits, neck, and feet) are places your body wants to protect. Being ticklish help us quickly squirm away from bug or animal bites.

Social bonding 😜

Tickling is a way families and friends play. Laughing and being silly together can build social bonds and help people feel closer.

Brain training 🧠

Some scientists think tickling might help kids learn quick reflexes.

Tickling works because it’s surprising. You can’t tickle yourself because your brain already knows what your hands are doing.

Also, laughing doesn’t always mean someone likes it. Tickling activates parts of the brain that control touch and emotions, and laughter can happen automatically even if the person wants it to stop.

Some animals, like dogs, respond if you tickle their feet. However, for them, it feels like an itch (called knismesis).

Fewer animals feel tickles the way humans do, which causes us to laugh and squirm (called gargalesis). Rats and gorillas respond by laughing, and even elephants tickle each other when playing!