Theory could finally explain mysterious desert ‘fairy circles’

The ‘fairy circles’ of Namibia – round patches of earth appearing in honeycomb patterns on the landscape – have perplexed scientists for decades.

The cause of circular shapes surrounded by vegetation has been the subject of debate. Termite engineering and the self-organization of vegetation have been two possible causes put forward.

But new research, conducted by the University of Strathclyde and Princeton University and published in the journal Nature, suggests a combination of the two factors may explain the phenomenon.

Dr Juan Bonachela from Scotland’s University of Strathclyde’s said:

“There have long been two theories on how these regular patterns, and especially Fairy Circles, are formed, and both theories are normally presented as mutually exclusive.

“Our findings harmonize both theories and find a possible explanation for regular vegetation patterns observed around the globe. In the case of Fairy Circles, termites remove vegetation on their mounds to increase moisture, which is essential for the insects’ survival in dry environments, thus creating the bare disk. Vegetation around the mound takes advantage of this water accumulation to grow, and this taller vegetation forms the circle. Regular repetition of the pattern results from different termite colonies competing next to one another.

“This behavior affects the whole ecosystem, allowing it to survive harsher conditions and recover from droughts much more quickly than if there were no termites.”

Dr. Bonachela added that: “The Fairy Circles remind us of the delicate balance of interactions necessary to sustain ecosystems.”

Similar patterns were found in Australia only recently

The collaboration between the two universities brought together expertise in different areas. The cause of the fairy circles was investigated with a multidisciplinary approach that included field data from four continents.

Computer simulations were conducted, allowing researches to explore theories on a variety of scales and to test different environmental scenarios. These simulations removed the financial and logistical restrictions that would have made testing theories on the ground very difficult.

The fairy circles can be up to 25 meters wide and give the landscape an otherworldly appearance that also resembles patterns on a cheetah or leopard. Until recently they were thought only to exist in the Namib desert, however in 2014 very similar patterns were spotted in Western Australia’s Pilbara region.

—–

Image credit: Tyler Coverdale, Princeton University; and Jen Guyton, Princeton University

The post Theory could finally explain mysterious desert ‘fairy circles’ appeared first on Redorbit.

redOrbit.com
offers Science, Space, Technology, Health news, videos, images and reference information. For the latest science news, space news, technology news, health news visit redOrbit.com frequently. Learn something new every day.”