for National Geographic News
What's your crop circles IQ? Test your knowledge of the uncanny artworks spotlighted by Google's home page today.
Answers at bottom.
1. Where did crop circles first appear?
2. Who or what was discovered to have created those early crop circles?
a. Ball lightning
b. Wind vortices
3. What is the science of studying crop circles called?
4. Wiltshire County, England, is the center of the crop circle phenomenon. What else is Wiltshire home to?
a. Tower of London
b. Canterbury Cathedral
c. Windsor Castle
5. What form have some crop circle artists included in their work to prove the designs are not natural occurrences?
b. Straight line
c. Perfect circle
More on Crop Circles
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Crop Circles Go Worldwide Overnight
Crop Circles in Tasmania Caused by Stoned Wallabies, Official Says
Video: Crop Circles 101
Crop Circles and More: History's Hoaxes
ON TV: Crop Circles, Airing Saturday, September 19
Crop circles first appeared in the fields of southern England in the mid-1970s. Early circles were quite simple and appeared overnight in fields of wheat, rape, oat, and barley. The crops were flattened, the stalks bent but not broken. Each year more than a hundred formations appear in the fields of southern England.
In 1991, Britons Doug Bower and Dave Chorley came forward and claimed responsibility for the crop circles made over the past 20 years or so, saying they had conceived the idea as a prank. Skeptics argue that the pair could not have been responsible for all crop circles worldwide—and that some of the work could not have been done by humans.
The phenomenon of crop circles has spawned its own science: cereology.
Wiltshire County is home to some of the most sacred Neolithic sites in Europe, built as far back as 4,600 years ago, including Stonehenge, Avebury, and Silbury Hill.
To combat a widely promulgated theory that crop circles are the results of wind vortices, some crop circle artists have produced designs with straight lines to show that the circles were not a natural phenomenon.