Isn’t the human body an incredible feat of nature?
Wikipedia: “In a 2008 study, 89% of students admitted to being ticklish on their right foot, 80% under their arm, 77% on their left foot, 77% on their ribs, 65% on their palm, 61% on their knee cap, and 51% on their stomach. 27% claim they are not ticklish at all.”
Let me say something to the (roughly) 27 percent. First, I am incredibly jealous, and second, I am sorry that you’ll never experience the joy of tumbling over with laughter storming the pit of your stomach.