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CIRCLES IN THE SAND


A dragon stirs deep under a desert. It breathes a poisonous gas as it goes. The gas bubbles up to the surface. There, it burns circles of bare dirt in the grass. Or so one story goes. No one has seen this mythical beast.





Yet some people in West Africa say it’s there. It’s how they explain mysterious dirt circles that dot the eastern edge of the Namib Desert. Thousands of circles stretch as far as the eye can see. Some are small. Others are wide. The dragon has been busy.


Searching for a Cause Scientists don’t believe in dragons. T ey believe something else causes these strange circles. Some think ants chew on the roots of the grasses. Others think a toxic plant may spread its poison and kill the grasses. T ese ideas are only theories. T ey


could be possible. Yet scientists have to prove a theory. Only then will a theory become a fact.


Desert Discoveries Norbert Juergens wants to solve this mystery. He’s a biologist. He studied 1,200 of the circles. Juergens looked for things all the


circles had in common. He tested the dirt and measured water in the soil. He made a list of animals and plants in the circles. He charted the weather. T en he studied his data.


18 NATIONAL GEOGRAPHIC EXPLORER


Mysterious circles of bare dirt dot this desert in West Africa.


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