One of the more startling things I learned in basic biology when I was in grade school was that our brains are cross-wired to our bodies. You know, left side of the brain controls the right side of body, & visa-versa. Worse, nobody could really explain why this was. Well, today in the Washington Post there's an article about a group of scientists who think they've figured it out. Turns out it has to do with basic optics and the evolution of limbs as locomotion.