Alltop.com

Why do we yawn? And why does yawning feel more contagious than the bubonic plague? A couple of the dudes from Vsauce offer a lesson on yawning that might leave you feeling a bit sleepy, but not in a snoozefest kinda way.

Bonus challenge: try not to yawn while watching the video.

Via The Kid Should See This.

Awake yet? Read more science-y stuff.