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- Anonymous2 decades agoFavorite Answer
2006-05-08 10:39:49 補充：
希望有幫助：Crop circles are areas of cereal or similar crops that have been systematically flattened to form various geometric patterns. The earliest recorded crop circle is depicted in a 17th Century woodcut called the Mowing-Devil. After the start of the hoaxes perpetrated by Bower and Chorley, the phenomenon of crop circles became generally known in the 1970s. Crop Circles shot into prominence in the late 1970s as many circles began appearing throughout the English countryside. To date, thousands of circles have appeared at sites across the world, from disparate locations such as the former Soviet Union, the UK and Japan, as well as the U.S. and Canada. Although the commonly accepted view today is that crop circles are a man-made phenomenon, paranormal explanations, often including UFOs, are still popular.http://en.wikipedia.org/wiki/Crop_circles