A German scientist believes he has an explanation for the strange rings of grass, called 'fairy circles', found across the Namib Desert in south-western Africa.
Norbert Juergens told Science magazine that he thinks it is a species of sand termites, Psammotermes allocerus, behind the mysterious rings.
The sand termite is said to clear the soil of grasses so rainwater can be kept in the ground instead of used by the grass.
Mr Juergens said: "This termite-generated ecosystem persists through prolonged droughts lasting many decades."
But he told IOL: "Despite the many hypotheses, the origin and the ecosystem function of fairy circles are still a much-debated mystery."
When studying the fairy circles, Juergens said sand termites were the only creature found in most of patches. He said most patches also had layers of cemented sand and underground tunnels - signs of sand termites, LiveScience reports.
It is also possible that the termites don't cause the circles but just live in them.
Fairy circles vary between two and 15 metres wide and are mostly found in Namibia, although they have also been seen in Angola and South Africa.
Sand termites were suggested as the cause of the circles in 2012 by scientist Eugene Moll before the theory was reinforced by Norbert Juergens in 2013.
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