The fairy circle mystery – Strange barren dots -- rimmed with tall grasses -- sprinkle a 1,100-mile stretch of Namibia's desert.
The fairy circle mystery – Known as "fairy circles," these dots have posed a mystery to scientists, who have yet to prove what causes them to pop up on the landscape.
The fairy circle mystery – Over the years, several theories have been battered around. The main hypotheses have pointed to gasses, poisons and social insects as the cause -- though none have been proven.
The fairy circle mystery – Last year, a paper was published in Science by professor Norbert Juergens claiming that fairy circles were the work of a species of sand termite, psammotermes allocerus.
The fairy circle mystery – Juergens argued termites created an underground oasis for themselves by eating the grass roots and killing it, thereby causing a subterranean water trap (without vegetation, water doesn't evaporate and remains underground).
The fairy circle mystery – Juergens based his findings on the fact that p. allocerus were the only insect species found consistently across the full stretch of desert where the circles are present, and were especially abundant around the circles.
The fairy circle mystery – Though many experts found his findings interesting, many remain unconvinced.
The fairy circle mystery – Walter Tschinkel, a biology professor at Florida State University, believes Juergens found a correlation, but not necessarily a cause for the formation of the circles.
The fairy circle mystery – Stephan Getzin, a scientist from the Helmholtz Centre for Environmental Research in Leipzig, Germany, recently put forth another theory with colleagues from Israel.
The fairy circle mystery – Getzin argues the circles are formed by a process known as "self-organization."
The fairy circle mystery – Basically, in arid climates, where water is scarce and soil nutrient-poor, plants face stiffer competition for resources. As a result, they 'organize' themselves at a distance to maximize what limited resources are available --ultimately forming strongly ordered patterns on the landscape.
The fairy circle mystery – There are similar examples in nature that are likely a result of self-organization. These include Niger's tiger bushes and spinifex grass in Australia.
The fairy circle mystery – Though these types of occurrences are rare, they are likely to occur in arid regions with nutrient-poor soil.