Have you ever wondered why seeing someone yawning creates in you the same urge to open your mouth? While scientists understand the physiological purpose behind yawning, why it is so contagious among social animals has puzzled them. According to Andrew Gallup, an evolutionary biologist at the State University of New York Polytechnic Institute and the paper’s author, yawning may be a way for groups of animals to adjust to each other and coordinate group behavior.
One usually yawns while moving from one stage of activity to another, which can be either waking up from a deep sleep or going to bed after a tiring day. Yawning has long been thought to be a means of expelling carbon dioxide and replenishing oxygen. But, now, it appears that yawning may have more to do with regulating the temperature of the blood to cool the brain. one discovery, published Infectious yawning sheds more light in the journal Animal Behavior.
When it comes to persistent contagious yawning between individuals, Gallup explained that this behavior may have evolved to increase alertness within a group. The idea is that if yawning indicates that a person is feeling sleepy, seeing them yawn may alert other members of the group. This compensates for the low alertness of the yawner and in turn increases the overall alertness of the group.
Gallup conducted a study last year to clarify this idea. They showed people several pictures that included threatening stimuli such as pictures of snakes and non-threatening stimuli such as pictures of frogs. People were first made a video of yawning and then they were shown pictures. Gallup then tested his ability to choose images from an array of pictures.
They observed that after watching people yawn, one could detect dangerous stimuli or pictures of snakes more efficiently. However, people’s ability to detect a picture of a frog remained unchanged, Science magazine reported.