After searching the four corners of the globe web, I have learned that a new take on an old riddle must include a new definition of an old appendage. Indeed, mankind has moved beyond use of its archaic, flesh-and-bone legs. At long last, have been replaced by our greatest discovery: the wheel.

Below, witness the ages of man, as the romping go-kart of youth is replaced by the urgent bicycle of the adult, to finally retire to the relaxed tricycle of old age.