Yawning isn’t the only bodily function that’s contagious. Japanese scientists have discovered that chimpanzees are more likely to urinate when they see other primates going No. 1 as well, as ...

Bournemouth University neuropsychologist Simon Thompson is an expert on yawning. In 2011, he posited that high levels of the stress hormone cortisol may be a direct cause of yawning. “We believe that ...