Fairy circles discovered in Australia may finally solve one of nature’s great mysteries

Fairy circles
CC BY 2.0 Wikimedia Commons

A new find seems to confirm how these odd circular patterns are formed.

Up to now fairy circles have only been seen in the Namibia grassland of southern Africa (pictured above). Researchers have come up with a handful of theories to explain these cool and curious circular patterns in the landscape, but a consensus has yet to take hold.

But with the discovery of this same phenomenon in the desolate Australian outback, scientists may have solved the mystery.

Aside from the obvious answer – fairies! – scientists have suggested that circles are caused by termites or ants, others have hypothesized they are the effect of carbon monoxide gas rising from the earth. Yet another idea holds that they are brought about by plants themselves in response to drought.

The discovery in Australia, research of which is published in the PNAS journal (Proceedings of the National Academy of Sciences), corroborates the third theory – that the plants organize themselves. From the study abstract:

The researchers combined fieldwork, remote sensing, spatial pattern analysis, mathematical modeling, and model analysis to demonstrate that the observed fairy circle patterns are self-organizing and are driven by positive biomass-water feedbacks that take place simultaneously throughout the whole system, and are not related to termite activity.

As there is not enough water in areas between desert and grassland – where fairy circles occur – for plants to form a continuous cover, individual plants organize themselves in this beehive pattern in order to maximize the little water that they receive. The result is like a grass carpet with large holes, which allows enough water for the plants in such a formation. You can see the pattern below as photographed in Australia (though the image is slightly hard to read) – the circles have an average size of four meters, though some exceed seven meters.

Fairy circles© Dr. Hezi Yizhaq/Ben-Gurion University of the Negev

"Using model simulations we were able to show that the Australian fairy circle gap patterns share similar characteristics with model-produced patterns," says Professor Ehud Meron from Ben-Gurion University of the Negev.

"Furthermore, we showed that the formation of the patterns is driven by a positive feedback between vegetation growth and water transport toward the growth location, very much like in the Namibian ecosystem, as we found in an earlier study.”

Dr. Stephan Getzin from the Helmholtz Centre for Environmental Research in Leipzig, Germany, says "For a long time, ecologists weren't convinced that plants in dry areas could organize themselves because the theoretical principles for these processes lie in physics." But with the confirmation of the new circles and research, it looks like it is in fact possible.

Getzin intends to study the phenomenon further and will continue looking for more sets of fairy circles in other arid and sparsely inhabited parts of the world.

(And while those who believe in the magic of fairies at work in the desert may be disappointed, is the magic of nature any less cause for awe and wonder?!)

Tags: Africa | Australia | Nature | Nature Blows My Mind


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