We have a new development in the mysterious case of the “fairy circles” of the desert
Science had almost closed the book on these mysterious’fairy circles‘, placing the blame squarely on the floor. To dispel any doubts, the researchers turned to the skies for more evidence, only to find that the story may not have been so clear after all.
Environmentalist Stephan Getzin from the University of GÃ¶ttingen in Germany has been at the center of the fairy circles debate for years after the first meet them in Namibia as an undergraduate student.
His most recent research could be the final nail in the coffin for (unsubstantiated) suggestions that termites are to blame for these weird rings. But it also adds new details to the theories describing how these strange spaces in the vegetation actually form.
Namibia’s vast expanse of fairy circles had baffled environmentalists for decades; Then, Getzin was alerted to the existence of a similar expanse of vegetation in the barren Pilbara region of Western Australia in 2014, providing him with the evidence he needed for his own hypothesis.
In 2017, we were given an answer: Fairy circles in Namibia and Pilbara are caused by plants competing for water around patches of soil that channel water at a faster rate.
Well, that’s part of the story. The science is rarely that simple, and questions remained as to whether the termites commonly found near these empty plots were just tourists or tiny loggers contributing to the desolation.
To purify the air once and for all, Getzin and his fellow researchers from Israel and Australia systematically probed dozens of fairy circles near the town of Newman in Western Australia, digging 154 holes over a length of 12 kilometers (7.5 miles).
Not only did they discover that the soil was also filled with the same levels of clay inside the circles, but they failed to find termite highways that would suggest their activity played a significant role in the development. circles.
To be doubly sure, they also mapped large landscape squares using drones, demarcating areas where vegetation was clearly decomposed by harvester termites.
“The gaps in vegetation caused by harvester termites are only half the size of fairy circles and much less orderly,” says Getzin.
“Overall, our study shows that termite constructions can occur in the area of ââfairy circles, but the partial local correlation between termites and fairy circles is not causally related.”
But this revisiting of Namibia’s patchwork of mottled vegetation has also added new details to their formation.
Until recently, most research had focused on fairy circles of relatively consistent size and distribution. Getzin was curious what environmental conditions described the threshold for their training.
Using images from Google Earth, Getzin and his team identified a range of structures that weren’t quite the usual size and shape of fairy circles, but still indicated a similar formation.
Some were over 20 meters (66 feet) in diameter, eclipsing the usual maximum diameter of around 12 meters (39 feet). Others were laid in drainage pipes or formed in unusual areas like car tracks.
They might not be as eye-catching as the polka-dot plains that stretch out on the horizon, but these goofy cousins ââto more famous fairy circles help better define the types of conditions that give rise to the phenomenon. .
“Here, our studies of soil moisture have shown that under such varied conditions, fairy circles function less like reservoirs of water than under typical homogeneous conditions where they are extremely well ordered,” says Getzin.
Science has a habit of keeping arguments alive long after the evidence seems conclusive. Without a doubt, there is more to these weird outback circles to say, but we can probably declare them a lot less mysterious.