I would like to know. Why are we ticklish? Why did humans evolve to be ticklish? Why Are We Ticklish? Scientific Explanations Behind the Sensation. It's a defense mechanism. One theory says that the tickling response is because a version of it has been observed in primates. With that in mind, there's thought that tickling could be used by caregivers to help children develop defense skills for survival. Scientists found being tickled stimulates your hypothalamus, the area of the brain in charge of your emotional reactions, and your fight or flight and pain responses. When you're tickled, you may be laughing not because you're having fun, but because you're having an autonomic emotional response. Tickling likely serves as a warning signal and training to protect ourselves. It has a secondary feature in humans, other primates, and rats it seems, to facilitate social bonding. https://tickleinva.freeforums.net/thread/229/why-ticklish