The term "crop circle" or "circles" was created by a researcher, Colin Andrews, to describe the strange circles and complex geometries(复杂的几何图形). He has researched what has shown up in fields of wheat, barley, rye, corn, soy beans and other crops for years.
There are numerous theories(理论)that have been given to explain crop circles of unknown origin(起源). It is notable for most people that when crop circles have been made by human hands, the plants themselves are damaged. But the plants in the stricken area continue to grow and ripen, and none of the stalks are broken nor the seed heads crushed.
Another strange thing about these particular types of crop circles is that the genetic(基因的)structure of the plants themselves has been changed. This does not happen to the crop circles that have proven to be the work of pranksters (玩恶作剧).
In 1966, in the small town of Tully Queensland, Australia, one of the most famous accounts of a UFO, as well as the possible link to crop circles, was given. A farmer was working on his farm and said that he saw a saucer-shaped craft (飞行器)fly 30 or 40 feet above a swamp (沼泽地)and then fly away at extremely high speed. The farmer decided to look into the area where he thought the craft had been hovering (盘旋)and he found the plants there intricately woven (杂乱地编织) in a clockwise pattern.
The crop circle phenomenon (现象)became a very hot topic during the late 1980s. No less than 12,000 genuine crop circles have been discovered all cross the world. In countries like the former Soviet Union, the UK, Japan, the U. S. and Canada, this strange phenomenon continues to appear and baffle anyone who observes it because no rational explanation exists. In a wheat field in Monroe County, Tennessee, a pattern ranging about 150 feet in diameter(直径)was discovered on May14, 2007. Captain Bryan Graves of the local sheriff's department discovered it while flying.
The crop circle phenomenon has never stopped appearing across the world since it was discovered. Could it be that extraterrestrial (来自天外的)beings are trying to communicate with humans? If so, what is the message they are trying to send? The mystery continues.
