Why when someone yawns near you you always repsonse and yawn?
819788
Sympathetic yawning is a good answer.  But a yawn is actually a deep inhale, it may be that for some reason there is a slightly lower amount of oxygen in the air and that particular location and you are both simply trying to get more air.
304410
I can't remember where I heard this but someone told me it's an empathetic response. Like the more in tune you are to others feelings, the more likely you are to yawn when you see someone else do it.
335953
u yawn when u do not have enough oxygen in ur blood, when u r tired ur lungs get lazy. u might have lazy lungs
922965
THE TRUTH IS that we don’t completely understand why people, or animals for that matter, yawn. It’s widely assumed that yawning occurs because we are tired or bored or because we see someone else doing it, but there isn’t any hard evidence to support these beliefs.\n\nThe most plausible explanation, and the one that is taught in medical school, is that we yawn because oxygen levels in our lungs are low. Studies have shown that during normal, at-rest breathing, we don’t use anywhere near our lung capacity; for the most part, we just use the air sacs at the bottom of the lungs. If the air sacs, called alveoli, don’t get fresh air, they partially collapse and the lungs stiffen a bit. As a result, it’s believed, our brain prompts the body to either sigh or take a yawn to get more air into the lungs\nalso when we someone else yawn if someone else yawns, we are naturally competitive so if someone else is getting more oxygen, our body wants more.
1170939
From what I've read, we are not sure exactly why that happens, but many doctors and scientist believe is is due to a mental reaction that sees a person yawn and believes you should do so as well.  Yawning is a response to a lack of oxygen in the brain under idle conditions, such as standing around or sitting in a chair.  So when you see someone yawn, your brain triggers a yawn to make sure you are also not starving your brain.
394382
Yawns are contagious because people naturally emulate what they see others doing. For more, read a section in the Tipping Point by Malcom Gladwell.
15767
People sometimes yawn when they are bored.  This reminds others that they too are bored.  Have you ever seen someone on a roller coaster yawn?  Fortunately you have asked an interesting question, otherwise I would likely be forced to yawn <G>.
65932
From straightdope:\n\n"nobody really knows. Fact is, we don't know why people yawn, period.\n\nIt was long believed you yawned when there was too much carbon dioxide and not enough oxygen in your blood. A part of your brain called the brain stem detected this and triggered the yawn reflex. Your mouth stretched wide and you inhaled deeply, shooting a jolt of oxygen into the lungs and thence to the bloodstream.\n\nSubsequently, you exhaled a lot of CO2. Often you'd stretch while yawning, which seemed to temporarily improve circulation. You yawned and stretched a lot more when you got tired because your breathing slowed down.\n\nOr so people thought. In recent years, though, a few radicals have said the preceding is all malarkey. Who knows, they say, maybe we yawn because it's too warm in the room.\n\nCecil isn't about to settle the issue here, and he doesn't need to. We merely observe that whatever yawn-inducing conditions prevail for you also apply to your friends.\n\nIf you're out late in some crowded dive, you're probably all tired, all warm under the collar, and all breathing the same stale air. You're probably all on the verge of a yawn, too, and the power of suggestion from seeing one person do it is enough to push everybody else over the edge.\n\nAdults rarely catch a case of the yawns from a child or animal, which tends to corroborate this idea.\n\nChildren usually have different sleep schedules and respiration rates from adults, so you would expect them to yawn at different times. Animals, on the other hand, often yawn not for physiological reasons but as a display of hostility, to which humans are evidently unresponsive."
339257
Yeah, the previous answers are right - lack of oxygen to the brain.\n\nBut the big question is why are yawns contagious? Even experts don't know that.
397407
Though the other answers are right (that yawning occurs to signal tiredness when the brain demands extra oxygen due to slipping performance), I would like to add another related comment.\n\nI recently read in the newspaper that scientists are discovering that yawning is a signal of compassion.  Researchers conducted studies in which participants watched videos of people yawning and the researchers measured the time between the yawn of the person on the video and the ensuing yawn of the study participant.  They then somehow effectively linked this elapse to compassion; what they stated was that the quicker you yawn after you see someone else yawn, the the more compassionate you are.\n\nRegretfully, I don't know the web address of the article, which I found intriguing, but I think it is worth your time to investigate.
346467
Yawns are not contagious, its an urban legend. Watch 'Mythbusters' on the Discovery channel.
37416
I asked the same question KIND OF go to the website below and it gives you the answers to the most common myths. Yawning is included in one of them.
213862
Why 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:
1077119
That always happens to me, but it has to do with my asthma.  Asthmatics sometimes don't get enough oxygen as a normal person would with ordinary breaths, and thus have to take deeper breaths (probably without realizing it) to get the job done.  I often find myself doing that... and yawning can have to do with that as well.  Sometimes when exerting a lot of energy, my asthma kicks in just a little bit, and I start yawning.\nAnxiety could also cause this.\n\nAlso it could just be that your other breaths, that aren't so deep, aren't bringing in enough oxygen-- so you have to rectify that by breathing more heavily every so often.\n\nIf you find it happening in certain locations, such as only at work-- it could be that the ventilation isn't that great, and fresh air isn't coming in as much as it should.\n\nAlso, being around a lot of smoke certainly won't make your lungs work any better.\n\nAll in all, there are a lot of explanations... I would just mention it to your doctor next time you go.  If it gets any worse, you should make an appt to see him.
196592
It is the brain requiring more oxygen. Which is why when someone else yawns you do to, it is your brain making sure that it has enough in case the other person takes it all. Not very likely to happen unless in a confined space, but the brain is always on survival mode.
480001
Virtually any stimulus associated with yawns -- including viewing, reading about, and even thinking about, yawning -- evokes yawns. (Are you yawning yet?) Yawning spreads in a chain reaction through a group, a compelling example of human herd behavior and a reminder that we are not always in conscious control of our actions. The urge to replicate an observed yawn is clearly an automatic response triggered by our brains.
363390
The 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. Other 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..." The contagion of yawning is interspecific (i.e., try yawning in front of your dog). Ironically, yawning in public is generally regarded as impolite in the West, but came into fashion in polite French society for a brief period in the late 18th century. Oddly, sometimes sympathetic yawning may be caused by simply looking at a picture of a person or animal yawning, or even seeing the word "yawn".\n\nAdelie Penguins employ yawning as part of their courtship ritual. Penguin couples face off and the males engage in what is described as an "ecstatic display," their beaks open wide and their faces pointed skyward.