The Namib Desert hosts some strange circles of barren land that have been called “The Fairy Circles”. Several explanations revolved around the bizarre formations, starting from supernatural forces and ending up at poisonous gas and subterranean insects. However, scientists might have found the answer.
Researchers at Princeton University, Glasgow University of Strathclyde, and several other institutions gathered and initiated a study that found the explanation for the barren circles. The Namibian Fairy Circles are the product of two ecological forces. They showed that the landscape formations are the result of termites and self-organizing plants (plants that either stick together or disperse in search for available resources).
The formations are found at the boundaries of the desert and grasslands. More exactly, they are hexagons of bare soil surrounded by tall grass. There are millions of such formations. Varying from two to 35 m in width, they are spread all around the Namib Desert in Namibia, Southern Africa.
Explanations on the phenomenon varied throughout the years. The circles have been attributed to toxic gases, poisonous shrubs, grazing ants, subterranean termites, self-organizing plants, and locals even believed they were the product of supernatural forces. However, the root-eating termites and self-organizing plants are our winners.
The termite hypothesis states that Psammotermes allocerus (a species of underground termites) are killing the plants growing above them, leaving moist patches of barren soil. In their attempt to create water traps, they end up reshaping the landscape.
The plant hypothesis follows the idea of the competition of plants for areas with limited access to water and their peculiar growth habits. The Fairy Circles are situated exactly where desert transitions to grass, therefore there are not enough conditions to sustain a continuous vegetation. This is why the plants organize themselves where they can get their resources, explaining the chaotic pattern they form.
However, neither of the hypotheses stands on its own. The presence of termites cannot explain the tall grass present at the edge of the circles, while the organizing pattern of the plants does not explain why these circles suddenly die. Also, such a behavior is not present in other self-organizing plant formations.
Yet the scientists discovered the answer. What explains best the behavior of the Fairy Circles in Namibia is the interaction of both termites and self-organizing plants. This hypothesis offers a perfect description of the circles and can also be applied to similar formations around the globe.
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