8 October: World Sight Day: Eyes

The second Thursday in October is World Sight Day, so here are 10 things you might not know about the organs responsible for sight, eyes.

1. It's commonly believed that our eyes never grow and stay the same size throughout our life. This isn't true. Our eyeballs grow a lot in the first two years of life and there's another growth spurt at puberty. So a newborn baby's eyeballs measure about three fifths of an inch front to back and an adult's measures just under an inch. A human eyeball weighs about 28 grams.
2. Contact lenses cannot get stuck behind your eye. There's a membrane between your eye and eyelid which stops that from happening. They can get stuck under your eyelid, though.
3. The most common eye colour is Brown. Originally, all human beings had brown eyes – so if you have Blue eyes, you're a mutant! Blue eyes result from a mutation of the gene which produces brown eye colour, diluting it to blue. It's thought the first blue eyed person was born between 6,000 and 10,000 years ago.
4. Eye muscles are the fastest muscles in the human body. The movement of our eyes to look at something in our peripheral vision is the fastest voluntary movement our bodies make. Eye blinks are pretty fast, too. It's possible to blink at a rate of five times a second – hence a blink lasts about 100-150 milliseconds. We tend to blink more while talking. The average person will blink about 4,200,000 times a year.
5. Some interesting facts about animals' eyes. Eyes are said to have developed in animals about 550 million years ago. Scientists have noticed that predatory animals tend to have pupils shaped like vertical slits, which help them judge distances. The animals they prey on tend to have eyes with horizontal pupils which helps with panoramic vision and looking out for predators.
6. An ostrich's eye is bigger than its brain.
7. An irrational fear of eyes is called ommatophobia. When a person has two different coloured eyes it is called heterochromia.
8. The iris of your eye has 256 unique characteristics. Your fingerprint has just 40, which is why retina scans are so often used for security purposes.
9. The floaters you may be able to see are strands of protein floating in the vitreous of your eye.
10. Tears are produced to lubricate the eye and get rid of foreign bodies. Why we produce tears as a result of strong emotions, scientists have never figured out. We do know, however, that newborn babies cry without producing tears – it takes about a month for the tear ducts to start working, that as we get older we produce fewer tears, and that if an astronaut cries in space their tears aren't shed, but collect in their eyes and make them sting.

See Also: Sight

Killing Me Softly

Sebastian Garrett is an assassin. It wasn’t his first choice of vocation, but nonetheless, he’s good at it, and can be relied upon to get the job done. He’s on top of his game.

Until he is contracted to kill Princess Helena of Galorvia. She is not just any princess. Sebastian doesn’t bargain on his intended victim being a super-heroine who gives as good as she gets. Only his own genetic variant power saves him from becoming the victim, instead of Helena. 

Fate has another surprise in store. Sebastian was not expecting to fall in love with her.

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