Humans’ real specialty is checking each other out. We’re so good at it, we do it without even being aware of it. With the help of the latest eye-tracking technology and scientists from Sussex University, we show some unsuspecting volunteers what their eyes really get up to. We are also very skilled at gauging depth and distance. Nigel discovers how top baseball players manage to track a ball coming towards them at high speed. This skill is an extreme example of the basic hand/eye co-ordination that we all acquire as we grow up.