A new study suggests that sand termites may have formed Africa's fairy circles (Photo : Reuters)
The African fairy circles have baffled scientists since they first appeared. The bare patches of desert, commonly rimmed with whiskery patches of grass, mark a 2000-kilometer strip of desert spanning from Angola to northern South Africa. Their presence has forever been a mystery, shrouded in folklore and tall tales, until now.
Ecologist Norbert Juergens thinks he may be the first to solve the mystifying puzzle. Following in the footsteps of Walter Tschinkel, a biologist at Florida State University in Tallahassee, Juergens explored the circles' liveliness. Tschinkel had noticed that the certain formations arose and other vanished over his four-year study that began in 2005, estimating that each circle has a lifespan of 41 years, but he could never explain way. That's when Juergens took the baton.
During his study, which prompted 40 field trips and included roughly 1200 separately fairy circle samples, Juergens discovered that one particular species was present at every fairy circle he visited.
The sand termite is an "extremely clandestine" insect that seemingly "swims" through the sand, Juergens noted, leaving behind tiny, discrete tunnels. They have no complex underground pathways, no nests and only seldom appear at night. He cites that other scientists may have missed the sand termites presence by digging too aggressively.
Juergens believes that the termites damage and feed on the grass roots, slowly forming the fairy circles in the process. He's still unclear as to why the circles eventually die, but believes that other predatory insects may play a significant role in their destruction.
He's convinced that the sand termites build the circles purposefully to maintain body moisture in order to survive. In the dry, arid desert, the fairy circles allow the rainwater to seep into the porous sand.
"These bare patches are water traps," Juergens says. "Over the years, I didn't measure 1 hour with less than 5% water at 60 centimeters, which is certainly wet enough to support termite life."
The stored water is also believed to sustain the tall grass that grows along the outer edges of the circles. During the rainy season, the termites venture to the grasslands for nourishment but return to their fairy circles during the long desert drought seasons to feed on their belts of grass, spreading fairy circles across the African desert.
Although Juergens stands fast by his findings, Tschinkel and other scientists are skeptic, citing that more information is necessary. "Juergens has made the common scientific error of confusing correlation-even very strong correlation-with causation," Tschinkel said. "If Juergens claims termites are killing the grass, he's got to show that they're actually attacking living plants. That's not easy to do, and he didn't do it."
There may still be missing pieces to the puzzle, but Juergens is headed in the right direction. One of Africa's biggest mysteries is one step closer to being solved.