An expert believes he knows why hundreds of sheep were walking in a circle for nearly two weeks straight in China.
Footage of the phenomenon went viral last week and captured the attention of people across the world.
And after no one could put their finger on why the sheep were behaving this way, one UK agriculture expert has come up with a theory.
Matt Bell, from Gloucester's Hartpury University, told Newsweek the sheep may have become anxious after being closed in a pen for too long.
"It looks like the sheep are in the pen for long periods, and this might lead to stereotypic behaviour, with the repeated circling due to frustration about being in the pen," he said.
Other experts, meanwhile, believed the phenomenon could be the result of the "circling disease" - listeriosis - but that would be unlikely, given it would usually cause death within 48 hours.
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