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We've all heard that yawning is contagious, so how long are you able to last while watching
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this video? Once you've yawned, click here on the screen, or use the link in the description
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below to see our video explaining why we yawn in the first place and why it's contagious.
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Still here? There might actually be a reason why you didn't yawn at all. Make sure you
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watch our other video, here, to find our why.
