Humans have been wearing shoes for some 40,000 years, but it wasn't until more recently that elevation entered the equation [source: Trinkaus]. Footwear changes how people walk and can even cause broader physiological effects. But when you wear high heels, that transformation can become particularly unpleasant.
Sure, given enough dedication to height enhancement, you might eventually end up with smaller calf muscles – good for looking slender, we suppose, although not for any practical purposes -- but the balls of your feet will be smashed, your toes will be squashed together and your feet may eventually curl inward in what we can only suppose is the fetal position a foot assumes under extreme duress [source: Britt]. We know this thanks to a study on 3,300 men and women.
So basically, the lesson here is: When you jam your feet into a pair of heels, that pain you feel is millions of years of evolution punishing you for your efforts.