Has the Enigma of Namibia's Fairy Circles Finally Been Solved?

Stretching from southern Angola to northern South Africa, Namibia’s desert landscape is dotted with fairy circles, also known as fairy rings. These barren circles are encircled by a ring of native brownish-green grass called Stipagrostis. The circles can measure between 7 and 32 feet (2 to 10 meters) in diameter, with distances of 16 to 32 feet (5 to 10 meters) between each. From a bird’s-eye view, they resemble a cheetah’s speckled coat, scattered across the reddish-orange sands of the Namib.

The Himba people of Namibia believe that the fairy circles (or fairy rings) are created by spirits or gods. Some even claim that these formations are the footprints of the Himba god Mukuru. Outside of indigenous traditions, various theories explain the circles, ranging from termites devouring the grass to toxic gases, fungi that kill plants, or competition between plants for water. There are even some who speculate UFOs might be the cause.

Dr. Stephan Getzin, an ecologist at the University of Göttingen in Germany, has uncovered compelling evidence that plant water stress is responsible for the formation of the mysterious fairy circles. His findings were published in Perspectives in Plant Ecology, Evolution and Systematics in October 2022.

How Plant Water Stress Creates Fairy Circles

Between 2020 and 2022, Getzin and his research team collected soil and plant samples from 10 different regions of the Namib Desert where fairy circles occur. The study focused on gathering data from plants and soil both before and after rainfall, a challenging task in the desert. Fortunately, 2021 and 2022 proved to be particularly rainy years.

Getzin's team discovered that within weeks of rainfall, the grasses forming the outer ring of the fairy circle absorbed all the water from the top 8 inches (2 meters) of soil inside the circle. This led to the death of plants within the circle after just three weeks, giving the edge plants the best chance for survival.

"In the intense heat of the Namib, the grasses continuously transpire and lose water. As a result, they create moisture vacuums around their roots, drawing water toward them. Our findings strongly support the work of researchers who have demonstrated that water in soil diffuses rapidly and horizontally in these sands, even over distances greater than 7 meters," said Getzin , in a press statement.

Here's the process: In hot, dry areas where rainfall is rare, it's not just animals that compete for water. Plants too have evolved survival strategies. As plants lose water through their leaves, they must absorb water from their roots. In the case of the Namib fairy circles, established grasses draw water from the center of the ring, depleting resources and causing newly sprouted grasses to wither in the middle.

Vegetation growing in unique patterns is not exclusive to Africa. Similar formations of what scientists term self-organizing vegetation have also been found in Australia, America, and Asia, where plant life creates grids, gaps, stripes, and labyrinths in various landscapes, such as peat bogs and mussel beds. These patterns are often referred to as "Turing patterns," after scientist Alan Turing, who first introduced the idea.

Scientists remain uncertain about the exact reason why vegetation in Namibia grows in circles, but some researchers suggest it could be linked to the amount of rainfall and the slope of the landscape. Regardless of the cause, the study strongly indicates that plant water stress is at the core of the fairy circle phenomenon in the Namib Desert. Perhaps fairies aren’t the true inhabitants of the desert after all.