Why do we yawn and why is it so contagious?
(WYTV)  Yawning is a primitive reflex. Most animals yawn  birds, reptiles, mammals and even some sharks. We might suddenly yawn even if were not tired at all. Scientist think the reason we yawn has a lot to do with our brain temperature. Yawning happens less during the winter when temperatures are cooler. A nice, long yawn brings in air, which your body can use to cool or stabilize your brain temperature. Yawning also compresses the muscles of the face and drives oxygen-rich blood up to the brain. It might have something to do with mirrored behavior. Seeing someone else yawn in a boring meeting triggers you to yawn as well because youre in the same environment, exposed to the same temperature. As social animals, we are inclined to mimic others actions if we think they will also benefit us or create social bonds. Its the same with laughing. If you see someone laughing long enough, you tend to start giggling, too. If you cant stop yawning, try breathing deeply through your nose for a few minutes. That should wake you up.