The Eyeball as a Tennis Ball

Think of the eyeball as a tennis ball with a little slit in it (the iris) so you can let light in. The light goes in and hits the inside back curve of the ball—and much of the rest of the inside of the ball, too. But that area straight back is prime data collection territory. It also happens to be where the optic nerve is and a whole generous cluster of cones. Remember rods and cones? The cones are better for color and precision and the rods are better for black and white, poor lighting and catching movement. Humans usually want the cone-quality input but at times the rod-quality data is more useful. But oh, the choice of which you lean into has so many more implications for you than 'just' how you compose a picture of your world!