Huffington Post - Stephanie Pappas, 06/27/2012
The smallest "fairy circles" are about 6.5 feet (2 meters) in diameter, while the largest can be almost 40 feet (12 m) across. Eventually, plants move back in, re-colonizing the circles and leaving only slightly indented "ghost circles" behind.
In the sandy desert grasslands of Namibia in southern Africa, mysterious bare spots known as "fairy circles" will form and then disappear years later for no reason anyone can determine. A new look at these strange patterns doesn't solve the wistful mystery but at least reveals that the largest of the circles can linger for a lifetime.
Small fairy circles stick around an average of 24 years, while larger ones can exist as long as 75 years, according to research detailed today (June 27) in the journal PLoS ONE. Still, the study sheds little light on why the circles form, persist and then vanish into the landscape after decades.
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