I have noticed when in a group one yawns, another one ( or more ) from the group also yawns..why?
337591
because yawns are catching and a yawn is when you are tired and need a hugeee gulp of air so of course if someone in your group has yawned and inhaled alll the air then you nearly suffocate cause you've got no air so you have to yawn to try get some air before you collapse. so blame you friends for snatching the air from your lungs making you yawn !!!!!!!!!!!!!!!!!!!!
207785
Next to questions that males ask regarding the size of their manhood, this has to be the second most asked question here!\n\nWhy we yawn when we see others yawning has baffled scientists for ages and a number of suggestions have been put forward to explain this phenomenon. What we do know is that yawning is an involuntary action- our brain does it without us thinking about it, even very young babies yawn showing that it's a built in action (Chimps do it too by the way). Just thinking about yawning can trigger the bit of the brain that causes a yawn. http://www.ratlab.co.uk/yawn.htm...\n\nMore theories can be found at the links below: \n\nhttp://www.world-science.net/exclusives/...\nhttp://www.yesmag.bc.ca/questions/yawn.h...
775112
It's a sympathetic reaction that makes them contagious.  A yawn happens when your body is not receiving enough oxygen.  You yawn when someone else yawns because of this sympathetic reaction.  Mythbusters did an experiment on this topic on one of their shows.
456058
Oh ardent one, I hope I understand your question.  I know I'm ahead of the game because it didn't cross my mind, you'd want a boyfriend.  I help people deal with various issues in life and I have noticed that when they realize something or they get a release of sorts, they often yawn.  I find it fascinating.\n\nDo I notice a particular emotion just prior to yawning?  Yes, on the rare occasion that I feel intimidated, I notice I yawn.
178925
The reasons for this are unclear; however, recent research suggests that yawning might be a herd instinct.\n\nHerd Instinct\n-------------\nThe so-called herding instinct is a social tendency in humans to identify with and model many behaviors and beliefs after a larger group of individuals with whom they identify. This is sometimes referred to as "following the herd." Such people are sometimes labelled with the derogatory term "sheeple."\n\nSince the herding instinct includes both behavior and belief, the term 'herd behavior' describes only a part of this complex phenomenon in humans.
17567
Yawning is one of those bodily mysteries that scientists haven't completely figured out yet.  The best theory I could find was that you yawn because you're not getting enough oxygen to the brain (maybe there is a lack of oxygen in the space you're standing).  Whenever you're aware of someone yawning, it activates a reaction in your subconscious mind that acts as a threat response.  Basically, whenever you see someone yawn, it makes you body think there is a shortage of oxygen too, and you yawn in response.  No one knows if this is actually the case, but I think that it is a good theory.
371295
Yawns are contagious because most of us when seeing another yawn, we will hold our breath unintentionally...those few seconds cause a lack of oxygen which is what makes people yawn! Try it out next time you see someone yawn...make a point to make sure you breathe regularly and you'll see that you won't yawn.
41848
I have a theory on this to share.\nMay be yawning is not a chain reaction at all.\nIts just our reaction to the state of things, outside as well as inside our body.\nFor instance, we feel sleepy when our brains are tired or refuse to process. Result is that we all yawn when after a tired game, after a boring speech.\nMay be even when there is lack of sufficient oxygen.\nWe all have different reaction times though. Thats probably the reason why its being mistaken to be a chain reaction.
288559
A yawn is a reflex of deep inhalation and exhalation associated with being tired, with a need to sleep, or from boredom. \n\nThe yawn reflex is often described as contagious: if one person yawns, this will cause another person to "sympathetically" yawn. The reasons for this are unclear; however, recent research suggests that yawning might be a herd instinct.\n\nHerd instinct\n------------\nThe so-called herding instinct is a social tendency in humans to identify with and model many behaviors and beliefs after a larger group of individuals with whom they identify.\n\n\nOther theories suggest that the yawn serves to synchronize mood behavior among gregarious animals, similar to the howling of the wolf pack during a full moon. It signals tiredness to other members of the group in order to synchronize sleeping patterns and periods of activity. It can serve as a warning in displaying large, canine teeth, thus proclaiming, "don't attack while I am sleeping...
449198
Not contagious but we are affected by an others yawning. This is called "Alolomimea" funny name but its what its called. Scientists believe that the reason we react to other people yawning is because in our early history ("caveman times") we needed to regulate our sleeping patterns so we could all survive together. Kinda like one for all and all for one deal. So if one of our cavemen buddies was tired we would all need to rest so we could all effectively hunt as a unit. It served  us as a natural "hey dude im tired lets take a break so we can hunt better and not die" It's a true story!
15668
~~Ya this happens to every one...every single human being as well as animal! This is normal...when there is oxygen shortage in our lungs or when we feel relax we yawn. So dont worry and start yawning!~~
257093
Not sure...but you don't have to see someone yawn to make you yawn. Just hearing a yawn is enough, sometimes.
1037619
Because its physiological.\n\nNumber one, Yawns are caused by, indication of tiredness, stress, over-work or boredom, An action indicating psychological decompression after a state of high alert, and means of expressing powerful emotions like anger, rejection, apathy or tedium.  So when you see someone yawn, it may remind you of how tired you are, or stressed or whatever it might be.  Causing you to Yawn.  Even if you dont notice you saw someone yawn, your subconscious recognized the other persons yawn, and cause you to want to yawn.  Also, it may be your way of stretching, its also a way of streching your lungs out.  So basicly its a subconscious thing.
1051186
When a person yawns it is usually due to the lack of oxygen to the brain. When we see a person yawning our brain interprets  it as low level of oxygen in the air.As a result we yawn.
1159613
Ahhh... the age old question. lol\n\nThere are a number of theories. One is that when someone yawns, they take oxygen out of the air, and we need the oxygen so we yawn to get the oxygen we need. I'm not sure about that one. I think its just a joke.\n\nA more likely theory is that it relates back to the herd instinct. You know, monkey see, monkey do.
56869
The answer is, no one really knows why yawning is "contagious". Or why we yawn at all. One popular explanation is that yawning allows you to get rid of too much carbon dioxide in your system and increase your oxygen supply. This was disproved by Dr. Robert Provine and his research team in 1987.\n\nNow scientists are wondering if yawning is from our deep past -- part of our evolutionary history. Did a yawn signal to the group that it was time for everyone to retire to the trees and snooze? Did a yawn signal that we were all feeling cozy and warm about each other? Did a yawn signal something more like, "Gee, I know how you're feeling, I feel that way too."
433222
because they make one tired so then they person that isn't tires suddenly becomes tires and yawns. but yawns shouldn't make one another person yawn because the person is just releasing co2 from their bodies.