system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is thigh skin so much thinner than skin on other parts of the body?

I was looking up why thigh chafing happens so often, and apparently one reason is that thigh skin is so much thinner than skin on other parts of the body. Why is this?
gpt
Most people in our evolutionary past were normal weight or underweight and for them this was probably never really an issue (especially when you consider that they didn’t have clothing (or at least not shorts and trousers) for most of that time). So having thick, robust skin on the inside of your thighs was probably never selected for.