In the Namibian desert, millions of evenly spaced circles dot the landscape. Their edges are lined with knee-high grass, but nothing grows in the centers—not even when fertilized soil is added. The mystery surrounding the origin of these natural rings has inspired many theories over the decades, but none pan out to the satisfaction of everyone in the scientific community. Suggestions include the work of termites, sand-bathing ostriches and zebras, noxious plants and fungi killing circular patches of grass, subterranean gas, competing grasses, and levels of available nutrients in the soil. While most fairy circles appear in the Namib Desert, they occupy a 1,800-kilometer-long (1,100 mi) stretch that reaches Cape Province in South Africa. One aspect of the circles that indicates systematized organization is that they never overlap, causing scientists to speculate whether the circles are competing with each other in some way. Each fairy circle can expand between 2 and 20 meters (7–65 ft) in diameter and have a lifespan of up to 75 years. No one knows what causes them to vanish.
In the Namibian desert, millions of evenly spaced circles dot the landscape. Their edges are lined with knee-high grass, but nothing grows in the centers—not even when fertilized soil is added. The mystery surrounding the origin of these natural rings has inspired many theories over the decades, but none pan out to the satisfaction of everyone in the scientific community. Suggestions include the work of termites, sand-bathing ostriches and zebras, noxious plants and fungi killing circular patches of grass, subterranean gas, competing grasses, and levels of available nutrients in the soil. While most fairy circles appear in the Namib Desert, they occupy a 1,800-kilometer-long (1,100 mi) stretch that reaches Cape Province in South Africa. One aspect of the circles that indicates systematized organization is that they never overlap, causing scientists to speculate whether the circles are competing with each other in some way. Each fairy circle can expand between 2 and 20 meters (7–65 ft) in diameter and have a lifespan of up to 75 years. No one knows what causes them to vanish.
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