An Explanation of Why Humans Yawn by AsapSCIENCE

Mitchell Moffit and Gregory Brown of AsapSCIENCE explain the various theories on why humans yawn, including contagious yawning, and the role that mirror neurons play in it. Additionally, they have posted a video consisting of nothing but a series of people yawning to see how long viewers can last before they do likewise.

submitted via Laughing Squid Tips