Chicago Eyes - Fun Eye Facts

Fun Eye Facts

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Sailors once thought that wearing a gold earring would improve their eyesight.
The shark cornea has been used in eye surgery, since its cornea is similar to a human cornea.
The eye of a human can distinguish 500 shades of the gray.
The cornea is the only living tissue in the human body that does not contain any blood vessels.
Your eyes blink over 10,000,000 times a year!
The Atlantic Giant Squid's eye can be as large as 16 inches wide.
An ostrich's eye is bigger that its brain.
20/20 vision means the eye can see normally at 20 feet. 20/15 is better; the eye can see at 20 feet what another eye sees at 15 feet.
Eyes are the most complex organs you possess except for your brain.
Eyes are composed of more than two million working parts.
The eye muscles are the most active muscles in the whole body.
80% of what you learn is through your eyes.
It is impossible to sneeze without closing your eyes.
An ant has two eyes, each of which is made up of many smaller eyes. This type of eye is called a compound eye.
A worm has no eyes at all.
A chameleon's eyes can look in different directions---at the same time!
Unlike humans, guinea pigs are born with fur and with their eyes open.
Babies cry but don't produce tears until one to three months after birth.
Each of our eyelashes has a life span of approximately five months.
An owl can see a mouse moving more than 150 feet away, with light no brighter than candlelight.
Fish do not have eyelids. They do not require tears either, since their eyes are bathed by water, no special lubricant like tears is required.
Eyes are your most precious sense... care for them properly!

Why do animal eyes glow in dark?

In dark, the pupils are dilated, so that maximum amount of light enters the eye. When suddenly, light is shone in the animal eyes, it is reflected from the Tapetum lucidum. This is the reflecting layer behind their rod-rich retina. That is the reason why animal eyes glow in dark.

What is the red eye effect in a photo?

The red eye in the photo, is because the light when shone from a certain angle gets reflected from the choroid. The choroid has many blood vessels and therefore appears red. The 'red eye effect' can be avoided by changing the direction of the camera.

Do some animals have no eyes?

Some salamanders that live in dark caves and certain fish that live near deep Ocean beds have no eyes! This is because they do not need eyes, since in light never ever reaches them! Some of them have rudimentary eyes with permanently closed eyelids over them, while in some the eyes are totally absent.

We do not see some colors in flowers. Is that true?

That is true, though flowers look vividly colored, yet they are better than they appear! Flowers, like daisies, have an attractive colored zone around center. This zone does not appear different from the surrounding color to us, but the butterflies can see more colors in that zone. This is a special gift to the butterflies, since they have taken up the job of pollination.

Can butterflies see more than human beings?

That is true! Butterflies have compound eyes like many other insects. They see better than humans in ultraviolet range up to 300 nm. They require this ability to spot the central nectar bearing part of the flower. The flowers have a more colorful center, than what we can appreciate! This helps the plant in pollination.

Why can animals like cats and owls see well at night?

Nocturnal animals like owls have greater density of rods in their retina. The rods are responsible for vision in dark. Therefore they see better at night. Owls also have tubular eyes that increase the throw from the lens to the retina.