Natural Wonders: Namibia’s Fairy Circles

Some natural phenomena are so weird that they seem at first to have supernatural origins. Take the fairy circles in the Namib Desert. 

 These circular barren patches dot the sparse desert growth and range from 2 to 15 metres in diameter. Their apparent randomness and almost perfect symmetry have spawned multiple theories on their origins, ranging from practical jokes to supernatural influences. The Namib Desert and the Pilbara in Western Australia are the only places in the world where this occurs. The circles seem to be associated with arid climates and the genus Stipagrostis in the grass family. 

The Fairy Circles from above. Photo: Theo Allofs

 

Many myths in the region have grown up around them. According to some, the circles are the footprints of gods. Others say that underground dragons created them. The Himba people of northern Namibia believed that their ancestor, known as Mukuru, created the circles and imbued them with magic powers. The grass around the circles fed the cattle while the circles themselves allegedly protected them from predators.

Norbert Juergens at work.

 

More recently, others have speculated that termites somehow created the circles. A popular theory by biologist Norbert Juergens champions the idea that sand termites fed on the grasses within, creating an expanding circle as they went. Juergens first saw the circles in 1980 while studying plants in South Africa. This theory has been tested and discredited with the help of computer models. Termites would leave behind random clumps in the soil rather than such symmetrical patterns.

The circles are too symmetrical to be the random work of termites, scientists say.

 

In 2013, some scientists claimed that the circles came from underground competition between different grass species. Water is scarce and when it rains, the barren patch acts as a collector, becoming a reservoir for surrounding grasses that fight each other for this resource. The study was done on the fairy circles in Australia and found that the plants (similar to the ones in Namibia) organized themselves in a kind of “ecosystem engineering” to use the limited water as efficiently as possible. The team who discovered this, led by Stephen Getzin, is currently studying the Namibian circles.

Their explanation has been more accepted by the scientific community yet still remains unproven. So, the final explanation of how these circles came to be remains a mystery.

Finally, the circles seem to have their own lifespan. After 30 to 60 years, they peak at 12m wide before the grassland eventually consumes them.

Termites or underground plant warfare? Something is causing the Fairy Circles. Photo: Shutterstock