Mystery in Namibia: Researcher finds new clues to mysterious fairy circles

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Fairy circles in Namibia

Photo: Edwin Remsberg / VW Pics / Universal Images Group / Getty Images

Mysterious circular spots in the Namibia desert have long puzzled researchers. They appear in large numbers in the barren landscape and appear to be drawn as if drawn with a compass. Some of them are three meters in diameter, others more than 20. The so-called fairy circles can also be found in Australia. While desert grass grows around it, the interior remains bare.

Now the German fairy circle researcher Stephan Getzin from the University of Göttingen has found new evidence of how the “fairy circles” come into being during soil studies in Namibia. As he and another researcher write in a journal, these support the theory that the characteristic circles arise as a result of a lack of water.

Circle is optimal shape

There are two main competing theories among scientists about the cause of the circles. Some suspect that termites create the patterns by eating away the roots of the grasses. Others claim that when competing for scarce water, plants arrange themselves in a circle in order to get as much of the resource as possible. In the seemingly bizarre dispute, both sides fight for their point of view with ever new studies.

Getzin's current measurements show that the top soil in the desert in particular dries out quickly. It is therefore particularly dry inside the circles. Freshly germinated grasses therefore die before their roots reach the water in deeper layers. The researcher suspects that only larger grasses could survive.

The researcher uses geometry to explain why circles form when drought occurs: In contrast to squares or hexagons, a circle has a more favorable ratio of circumference to area. To put it simply, the grasses on the edge suck the water from inside the circles. Through a circular arrangement, each individual plant reaches the most water - a kind of self-organization in nature.

However, Getzin writes in his article that the self-organization of plants may not be the only reason why fairy circles form and persist. He encourages further investigation into how exactly the water in the circles flows from the center to the edge. The competition to solve the puzzle is probably entering another round.

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