Vision is the team captain of the five senses. Of course, hearing, tasting, smelling, and feeling are all important. But most humans get most of their information about the world through their eyes.
The first “eyes” in nature appeared on sea animals hundreds of millions of years ago. They were just light-sensitive patches on the skin. But sensing light was so handy for survival that true vision began to evolve. Over time, more complex animals became able to perceive colors, shapes, and motion.
Until about 5,000 years ago, most humans were hunters. That’s why human eyes are set up for stalking and killing prey. For instance, both eyes are in the front of the head, not on the sides. And they can tell apart colors so that humans can identify one plant or animal from another.
Today, few people hunt for food, and yet eyes are still important for survival. We use them to do things like read, roller-skate, and fly airplanes. We have also found ways to boost our vision. With a microscope, we can look at objects that are as tiny as blood cells. With a telescope, we can peer into galaxies that are 13 billion light-years away.
