The mystery of Namibia's desert 'fairy circles'

Humans have long sought ways to explain why certain planetary events occur, whether those are geological, heavenly, environmental or weather-related. But in the absence of science, humans have often turned to storytelling. 

Some ancient cultures believed the temporary extinguishment of the sun during a total eclipse was the result of some evil being trying to gobble it up. Earthquakes, volcanoes and tsunamis have been put down to the wrath of gods.  

Over the years, we have found scientific explanations for many of these phenomena but scientists don't always find agreement, as is the case with the "fairy circles" of Namibia. The circles are actually patches of bare soil surrounded by vegetation. They appear in their thousands in the Namib Desert. 

The fairy circles have largely defied explanation. According to local legend, they are footprints left by the gods or burnt patches caused by a dragon's fiery breath. Scientists have come up with theories that include the circles being formed by ostriches rolling around in the dust as well as contamination by radioactive materials.  

Plants or termites?

There are, however, two leading explanations for the formation of the circles — both of which have passionate adherents. One hypothesis suggests the circular patches are caused by underground sand termites that have cleared vegetation in the areas around their nests. The other claims plants competing for water can explain the pattern. 

Both camps fiercely defend the rigors of their respective hypotheses, but earlier this year a team of scientists published findings in the journal Nature suggesting both hypotheses were right. The appearance of the circles "cannot be explained by either mechanism in isolation." The team's computer models found the pattern could be best explained as an interplay between the termites and plants. 

Still, not everyone is happy with this suggestion. Dr Stephan Getzin from the Helmholtz Centre for Environmental Research in Germany, who is firmly on team plant, said at the time, that the research didn't address the presence of such circles in areas with no termites.

It seems, the mystery has not quite been solved.