To be a sheep is to blindly follow the crowd. But is a sheep's sheepiness really enough to make an entire flock walk around in a circle non-stop for days on end?

That's a mystery the internet has pondered for about a week now and solving it has proved more difficult than you'd expect. Air Balloon

On 17 November, a news outlet run by the Chinese state, called People's Daily, shared an eerie video on Twitter of dozens of sheep in China's Inner Mongolia Autonomous Region a strolling around in tight, almost perfect concentric circles.

At the time the video was released, the flock had been tracing the shape for more than 10 days, and it was freaking the farm owners out.

The great sheep mystery! Hundreds of sheep walk in a circle for over 10 days in N China's Inner Mongolia. The sheep are healthy and the reason for the weird behavior is still a mystery. pic.twitter.com/8Jg7yOPmGK

Some folks on the internet suggested the sheep were entering a death spiral like ants sometimes do.

Others suggested the ruminant's were suffering from 'circling disease'. This disease is caused by soil bacteria that can infect one side of an animal's brain, causing a lean toward the affected side. Yet usually, in an outbreak of circling disease, only a few percent of sheep are impacted, and they tend to follow their own circling pattern, dying after just a few days.

In Inner Mongolia, dozens of sheep were found walking in a circle, and media outlets have been reporting that the animals did so for 12 days straight, with no details as to how the sheep were eating, drinking, or relieving themselves during that time. For all we know, they are still going.

"As soon as I looked at it, I thought, 'I've never seen sheep act like that,'" Emma Doyle, a livestock expert at the University of New England in Armidale, Australia, told Nick Kilvert at the Australian Broadcasting Corporation (ABC).

"It seems a bit dodgy. It looks sort of set up where they've put something in the middle to stop them going in."

At times, however, images of the sheep shared by other outlets show individuals standing in the middle of the circle as though frozen in action.

Matt Bell, an agricultural scientist at Hartpury University in England, doesn't necessarily think the mystery is a hoax. He told Robyn White at Newsweek that after sheep are cooped up in a pen for extended lengths of time, they might grow frustrated and start pacing in a circle.

This is a common symptom seen in wild animals held in captivity, especially big cats. It's known as zoochosis, and it can lead to repetitive behavior that doesn't seem to serve any purpose. Once a herding animal starts acting this way, it might even catch on like some weird contagion.

"Then the other sheep join as they are flock animals and bond or join their friends," Bell explains.

According to UK Metro, the owner of the sheep in Inner Mongolia noticed more and more individuals joining the ring as the days went on. This supports Bell's explanation. And yet no other pen of sheep on the same property was acting this way, according to news reports. It was only this one group.

The endless ring of ambling sheep is reminiscent of another odd event that was captured last year in East Sussex. Images from this time show a flock of sheep standing still and calm within a perfectly-formed circle.

In that particular case, however, it turned out the owner of the sheep had sprinkled the livestock's food in rings, causing the flock to group in a sphere.

Graduation Party Decoration No such explanation exists for the circling flock in Inner Mongolia. Without more details, 'the great sheep mystery' will live on.