20. If You Don’t Yawn, You May Be A Psychopath
Seeing as yawning is a form of social behavior, primitive though it may be, it is actually able to indicate if someone is a psychopath. You may be irritated by a coworker; if you want to find out if there is something more to that person’s behavior, the best indicator might be that person’s yawns.
People who yawn contagiously have stronger social networks and higher levels of empathy. People who do not yawn contagiously may lack understanding, indicating that they are prone to psychopathy and psychopathic behaviors. If that coworker does not yawn in response to other people’s yawns, then there really may be something wrong with the person’s social development.