The other age old question: what's your perception?

A quick Google search puts the nature-nurture argument at 50-50, but sometimes it's difficult to see the line. Consider Person A who goes to a gym, drops a little weight, gets in shape, and in time feels better about themselves. Why do they? Well, there is a physical response to exercise and the release of endorphins which leaves a positive feeling. There is also a change in self-perception and self-esteem, but distinction is more blurred here: does the person feel better because they are physically more fit (yes) or because they are likely perceived to be more attractive to other people (also yes). This change has both internal and external influences and it's difficult to determine the overriding factor: the absence of one would still lead to an improved feeling of well being. What about more subtle factors, like one's voice, height, coordination or state of health? People can be quick to judge someone else by these factors and others which do or don't appeal to them. We know that. But how do these things shape someone, shape you? Would you act differently if you had straight hair and were four inchers taller? If you were 4'10"? Just as one guitar is unlike another and can make you want to play a country lick if it twangs or a jazzy chord if it sounds mellow, I would guess a body would shape a personality, both in how someone responds to their instrument and how others react to it. Whatever kind of instrument you've been given, part of life is figuring how to make it rock.