Strange circles found around the coastal Namib Desert in southern Africa have baffled researchers for decades. Hundreds of these arid circles, measuring between 7 to 50 feet in diameter, are dotted along the long desert. Two major theories have attempted to explain these so-called “fairy circles” throughout the years, and, interestingly, both may be true.
The Two Major Fairy Circle Theories and Recent Research
Some theorists believe that termites deep beneath the soil form the circles. This group claims the insects clear all the vegetation situated right above their underground nests. Since the soil becomes more permeable without vegetation, rainwater easily flows 50 centimeters below the earth’s surface and into their nests. This, theorists claim, helps form a healthy balance between both the termites and the local environment.
The second main theory behind the Namibian fairy circles is called the water competition theory. As the name suggests, the adepts of this theory believe the fairy circles appear due to intense competition for water between plants.
As long as the vegetation is dense, water levels are maintained and the plants have enough nutrients. However, lonely specimens that do not benefit from the shade of their companions are forced to grow longer roots, extracting water from deep within the soil.
In order to settle this debate, Corina Tarnita, an assistant professor of ecology at Princeton University, decided to look into this matter. She teamed up another Princeton ecology professor, Robert Pringle, to run some intricate computer tests.
They first looked into the termite model using computer models. Their simulation showed that it is very likely various termite colonies establish borders, which would then result in the circular patterns on the desert’s surface. Termite colonies are well known for fighting over territory. Whenever there’s a stalemate, they often form a border.
Both Tarnita and Pringle discovered that every single settlement was surrounded by about six neighboring colonies. This wasn’t only true for the Namibian fairy circles but also correlated to how termites in areas such as Kenya, Arizona, and Mozambique often behave.
Despite these findings, both researchers felt like they hadn’t done the water competition theory enough justice. Tarnita wondered if both theories could actually be right simultaneously.
Tarnita and Pringle ran a computer model that computed for both a large-scale termite pattern and a small-scale pattern resulting from plants fighting over water. They saw a real possibility for both of these theories to be true. Eventually, the researchers headed out to Namibia to see these fairy circles for themselves.
Once the scientists arrived at the Namib Desert, they found the larger circles made by termites, but they also spotted numerous smaller circles that hadn’t been noted before. These smaller circles measured about 20 centimeters in diameter and were roughly 20 centimeters apart from each other. This matched Tarnita and Pringle’s computer model perfectly, and it suggested that both theories could be simultaneously true.
Accepted By Some, Rejected By Others
After Tarnita and Pringle released their data to the world, it received mixed reviews from the scientific community. One of the strongest supporters of the termite theory, Norbert Jürgens of Germany’s University of Hamburg, said that he thought Tarnita’s work helped resolve the debate between termite supporters and water competition supporters. Jürgens now hopes for a “balanced discussion.”
One staunch water competition theorist, however, is not ready to admit both termite and water competition theories can co-exist. Stephan Getzin, who works at the Helmholtz Center for Environmental Research, reported on fairy circles observed in Australia last year. Getzin said that he hasn’t seen any termites in either the Namib Desert or the Australian Outback.
Therefore, Getzin believes
“the termite theory cannot be considered as a strong explanation [of the fairy circles].”
The Theoretical War Isn’t Over Yet
Although Tarnita and Pringle’s research attempted to resolve this issue, the back and forth between staunch supporters of either side will probably go on for some time. Jürgens has already called Getzin’s claim that there are no termites in the Namib Desert ludicrous. After years of work in the field, Jürgens believes termites are always present in areas where these circles appear. Perhaps only further studies will put this fairy circle debate to a close.
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