Why you should eat carrots

To care for your eyes, eat carrots. They really do make you see better. Vitamin A is known to prevent "night blindness," and carrots are loaded with Vitamin A. Deficiency of Vitamin A actually is a significant world problem, comparable to that of protein deficiency and second only to caloric deficiency.

Carrots also contain fiber, potassium, vitamin C, and beta-carotene, which may reduce the risk of heart disease and cancer. Carrots have zero fat content. One carrot provides more than 200 per cent of recommended daily intake of Vitamin A.

Carrots were first cultivated in 500 BC in the Mediterranean regions. The first carrots were purple, white, and yellow. They were introduced in Europe in the 1600s. Orange carrots - the ones we know today - were first grown in Japan in the 17th century, and later made popular by the Dutch. The famous cartoon character, Bugs Bunny loves carrots but strangely Mel Blanc, who played the voice of Bugs Bunny, was allergic to carrots. Carrots are a rabbits favourite food.

How sand dunes are made

The wind blowing across a desert piles the sand up in hills called dunes. Where the wind keeps changing its direction, the sand dunes have no particular shape. But when the wind blows mainly from one direction, crescent-shaped sand dunes which are known as barchans form.

Barchans may occur in singly or in clusters. When the wind drives sand forward, Seif dunes are formed. They are named after an Arabic word meaning 'sword.'

How often you blink

The muscle that lets your eye blink is the fastest muscle in your body. It allows you to blink five times a second. On average, you

blink 15,000 times a day. That's about 10 times per minute, or more than five million times a year. Women blink more than men.

Animals blink too, of course.

Some bird species, usually flightless birds, have only a lower eyelid, whereas pigeons use upper and lower lids to blink. Fish and insects do not have eyelids - their eyes are protected by a hardened lens.