Ever notice how many times your eyes blink?
Probably not, because we blink so fast. The average person blinks about 12 times a minute. That's an amazing 10,080 blinks in a kids day (14 waking hours). That's why when someone says "it happened in the blink of an eye," they mean it happened really fast.
How far can an eagle see?
A lot further than the human eye can see. An eagle can see a rabbit about 1 mile or 1760 yards away. Now the average person needs to be about 550 yards away to see the same rabbit. That's why when someone says "you must have eagle eyes," they mean you can see really far.
Does being color blind mean you only see in black and white?
Not exactly. People who are color blind just can't see things in as many colors as people who have normal vision, and they cannot see certain colors like red, green, and some blues. Not all color-blind people see colors the same way, either. That's why when someone says "you must be color blind," they mean you didn't pick out your colors too well.
If bats are blind, how do they "see" where they are going?
It is a common misconception that bats are blind. Almost all bats can see, and their sense of sight and smell is well developed, but these bats don't use their eyes to "see" where they're going. They use sound waves. They make high pitched sounds and then listen for the echoes caused when the sounds bounce off an object. Some bats can fly at a speed of up to 30 miles per hour. Their "radar" must be pretty good to fly that fast at night! Now you know why if someone says "you're as a blind as a bat," they mean you missed something or didn't see it.
If someone is nearsighted they can't see things near, right?
Actually it is the other way around. People who have nearsighted vision can see things that are near very well, but they have trouble seeing things far away clearly. The scientific name for nearsightedness is myopia.
People who have farsighted vision can see things far away clearly but have trouble seeing things close up. The scientific name for farsightedness is called hyperopia. Now that's a mouthful!