1. The average blink lasts for about 1/10th of a second.
2. The world's most common eye colour is brown.
3. The first blue-eyed person is said to have lived 6,000-10,000 years ago.
4. The eye is the fastest muscle in your body – hence why when something happens quickly, we say "in the blink of an eye!"
6. The only part of the body that has no blood supply is the cornea of the eye. It receives oxygen directly from the air.
7. People with blue eyes are more sensitive to pain than others.
8. You blink your eyes over 10,000,000 a year.
9. It takes the human eyes an hour to adapt completely to seeing in the dark. Once adapted, however, the eyes are about 100,000 times more sensitive to light than they are in bright sunlight.
11. Our eyes are always the same size from birth, but our nose and ears never stop growing.
12. Each of your eyes has a blind spot - where the optic nerve attaches to the retina. The brain is just smart enough to fool you into ignoring it.
13. Just behind our pupil is the lens - which is round, flat and thicker toward the middle.
14. Your eyelashes keep dirt out of your eyes.
16. In the right conditions and lighting, humans can see the light of a candle from 14 miles away.
17. In a very basic form, eyes are thought to have first developed in animals around 550 million years ago!
18. When you read or stare at a computer, you blink less often resulting in tired eyes.
19. The cornea is the transparent covering of the iris and pupil.
21. Our eyes are made up of over 2 million working parts.
22. The eyeball weighs around 28 grams.
23. Albinism affects melanin production; perhaps resulting in extra sensitivity to light and a red-eyed appearance.
24. Astigmatism refers to a curvature of the cornea or lens and toric lenses are prescribed to aid the individual's vision.
26. The average person blinks 12 times a minute (bet you just blinked!).
27. Ommatophobia is a fear of the eyes.
28. There are about 39 million people that are blind around the world.
29. Humans and dogs are the only species known to seek visual cues from another individual's eyes, and dogs only do this when interacting with humans.
31. Eyes contain around 107 million light-sensitive cells.
32. Some people are born with two differently colored eyes. This condition is heterochromia.
33. Around the world, about 39 million people are blind and roughly 6 times that many have some kind of vision impairment.