system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: From my understanding when you are tickled your body thinks it is under attack, so why is laughter the response your body gives to being attacked?
gpt
Some Anthropologists think that laughter evolved as a signal that an expected danger subsided. Imagine, if you were walking through the woods with a friend, and heard a rattlesnake, you'd be scared, but then when it turned out to be some weird plant blowing in the wind (IDK) you'd laugh, and people would know that meant you were all safe. You expected one thing and then got another, which is one of the definitions of humor. In the example, laughter indicated you found something funny, but it also indicated you were safe. When tickle fighting someone, at some point they have to stop short of injuring you, and laughing lets them know that you are still safe, once you stop laughing and start screaming, that's when you generally get tickled less.