The mystery of yawning: We all do it, but why?

 作者:韩易偷     |      日期:2019-03-01 01:02:00
By Simon Thompson (Image: Hulton Archive/Getty) WHEN I give talks about my work, I know that before too long the audience will start to yawn. Just thinking about yawning makes us do it, but the mechanisms behind this everyday behaviour are a mystery. Yawning is often the first thing we do when we wake up, but we also do it when we are bored, tired or anxious. It is a primitive reflex that we share with other animals, from fish to mammals. We first start yawning in the womb,