Have you ever seen someone yawn and then you get the urge yourself to yawn? Even reading the word "yawn" makes you yawn sometimes. Nobody is exactly sure why we yawn, but a study has been done to show that empathetic people are more likely to yawn than non-empathetic people. I think this is kind of interesting. I especially like the method they used to test this. A person from the study would sit near someone else and would yawn ten times within ten minutes and count how many times the other person yawned. Then they took that person and they did an empathy test consisting of looking at eyes and recognizing the emotions shown. People who score higher on the empathy test were shown to yawn more. Maybe a yawn is your body's way of saying "Hey, I feel you, man. You're tired, so I must be tired, too." Or something like that.
I especially love that this study broke the results down by majors. Engineering students are terrible at empathy and yawning. If you yawn in front of an engineering student, their first thought wouldn't be "Oh wow, they must be tired. I wonder if I can help them out in some way?" I think it would be something like "Hmm...that is the fourth time that person has yawned in 5.4 minutes. And the angle of the mouth's opening is 48 degrees. And I count 8 wrinkles in the corner of their eye's when they squint to yawn."
On the other hand, psychology students did very well. I would love to go to a psychology class and yawn in front of everyone. You would probably hear a giant garble of yawns for the next ten minutes.