why are yawns contagious?
967357
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."\n\nBetween 40 and 60 percent of the population seems to find yawning contagious. Researchers at the State University of New York conducted a series of yawning experiments. They determined that being self-aware (the ability to recognize oneself) and having the ability to see things from someone else's viewpoint means a person is more likely to find yawning contagious.\n\nNow you're thinking, what humans are not self-aware? Schizophrenics sometimes have trouble with self-recognition so they will not find yawning contagious. Babies won't yawn contagiously until they're more than a year old.\n\nSome birds and reptiles yawn. Most mammals yawn. My dog yawns, but that doesn't make me yawn -- I obviously cannot put myself in her paw prints. (But who can empathize with a creature that sleeps all day, then when she does bother to get up and join you on a walk, suddenly bolts after a squirrel and nearly tears your arm out of your socket? I have no idea what's going on in that dog's mind.)\n\nChimpanzees yawn too, and in fact, if they watch other chimps yawn, they're more likely to yawn too.\n\nSo, I guess the real answer is: who knows?
422922
It is also believed to be linked to social bonding.\n\nExperiments with chimps have shown that they also yawn when another chimp yawns.  Also videos (night video) in caves, where there is no light, where a certain species of monkey sleep - shows that they all yawn audibly before going to sleep.  Kind of a way of letting everyone know that they're there, even though they can't see each other.\n\nThis has probably carried through to humans.\n\nHave a look at http://www.theanswerbank.co.uk/Science/Question117042.html\n\nor\nhttp://webperso.easyconnect.fr/baillement/contagion-platek.html
361765
Not really sure---but just seeing the word yawn made me yawn--Thanks alot---yawns again---wonders about yawns--yawns again-- http://en.wikipedia.org/wiki/Yawn Why are yawns contagious? Getting kind of tired-- http://www.straightdope.com/classics/a2_309.html-- Why do we yawn? http://faculty.washington.edu/chudler/yawning.html A yawn reasearcher? http://psychology.drexel.edu/ECNL/  Huh? Sorry must be groggy--Pictures of animals yawning --Oh No-- yawning out of control-- http://www.animalyawns.com/ all this reading about yawning ---YAWNS deeply--- I'm getting so sleepy ---  It's hard to keep my eyes open--z z z z z z z z z z z z z z z z z z z z z z z z z z z z z z z
829322
1- During a yawn, there is a slight increase in pressure inside the skull (likely caused by slight increases in the amount of oxygen taken in during a deep yawn). This causes the cerebrospinal fluid (CSF), the fluid that surrounds the brain and flows through the brain's ventricle system, to be forced out faster than normal. That fluid enters the lachrymal (tear) system. That increase in fluid pushes out the tears.\n\n2 - the more simplistic reason may be that when you yawn you scrunch up a bunch of facial muscles. That causes the tear glands and ducts to be squished, forcing out some tears.\n\n\nTalks about yawning as well:\nhttp://en.wikipedia.org/wiki/Yawn#Causes_of_yawning
255818
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".
40340
An indication of tiredness, stress, over-work or boredom. \nAn action indicating psychological decompression after a state of high alert. \nA means of expressing powerful emotions like anger, rejection or apathy. \n\nYou see someone yawning.  You hear someone yawning.  You read about yawning. You think about yawning. \nNow, you want to yawn. If this describes you, then you have just "caught" a yawn. Between 40 and 60% of the population is susceptible to contagious yawns, but the reason why yawns are catching is unknown. Steven Platek, Ph.D. suggests that being aware of one's own mental state ("self-recognition") and the ability to see things from another person's point of view ("mental state attribution") may make people susceptible to contagious yawns.
687663
yawning is contagious because you watch the other person yawning.  However, over the phone it is not contagious.  Also, if you are sitting on the same room but do not see the other person yawning then it contagious.  It is a way of reciprocating unconsciously.
1078201
This question has taken me a super long time to answer -- I've spent much of the time yawning every time I try to research! It's true! Are you yawning yet? Humans yawn when they see someone else yawn, read about yawning, think about yawning, or even just hear yawning. I can barely keep my hands on the keyboard because once I yawn, I tend to stretch and then rub my face.\n\nThe 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."\n\nBetween 40 and 60 percent of the population seems to find yawning contagious. Researchers at the State University of New York conducted a series of yawning experiments. They determined that being self-aware (the ability to recognize oneself) and having the ability to see things from someone else's viewpoint means a person is more likely to find yawning contagious.\n\nNow you're thinking, what humans are not self-aware? Schizophrenics sometimes have trouble with self-recognition so they will not find yawning contagious. Babies won't yawn contagiously until they're more than a year old.\n\nSome birds and reptiles yawn. Most mammals yawn. My dog yawns, but that doesn't make me yawn -- I obviously cannot put myself in her paw prints. (But who can empathize with a creature that sleeps all day, then when she does bother to get up and join you on a walk, suddenly bolts after a squirrel and nearly tears your arm out of your socket? I have no idea what's going on in that dog's mind.)\n\nChimpanzees yawn too, and in fact, if they watch other chimps yawn, they're more likely to yawn too.\n\nSo, I guess the real answer is: who knows?
609665
Because they trigger the receptors in the brain to relax.  Yawning signals relaxation to other humans, thus causing themselves to inadvertantly yawn.  It's like human relation reflex.
329034
We yawn because of a lack of Oxygen. Think about it: when you yawn more air comes in and sometimes after a yawn you feel rejuvenated for a little while. But this is contagious because if you yawn you are probably in an Oxygen-deprived environment and everyone around you is going through the same lack of Oxygen. And yawning is related to sleep because when you're asleep you're barely doing more than breathing, beating your heart and dreaming which doesn't take up much oxygen but you still get the same amount of oxygen as you would awake in the same room so there's more oxygen to relax your brain and mind and everything else that might be tired.
272413
It is an instinctual social response.  Yawning signals to others in the social group that it is time to rest.
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.
963394
Heere are excerpts from the source:\nIn an effort to find the answer, the Finnish government recently funded a brain scanning study. The results turned up some hard-to-interpret, possible clues. It also confirmed the obvious: yawn contagion is largely unconscious. Wherever it might affect the brain, it bypasses the known brain circuitry for consciously analyzing and mimicking other people’s actions.\n\nThis circuitry is called the “mirror-neuron system,” because it contains a special type of brain cells, or neurons, that become active both when their owner does something, and when he or she senses someone else doing the same thing. \n\nMirror neurons typically become active when a person consciously imitates an action of someone else, a process associated with learning. But they seem to play no role in yawn contagiousness, the researchers in the new study found. The cells are have no extra activity during contagious yawning compared with during other non-contagious facial movements, they observed.\n\nBrain activity “associated with viewing another person yawn seems to circumvent the essential parts of the MNS [mirror neuron system], in line with the nature of contagious yawns as automatically released behavioural acts—rather than truly imitated motor patterns that would require detailed action understanding,” wrote the researchers, with the Helsinki University of Technology and the Research Centre Jülich, Germany. The findings are published in the February issue of the research journal Neuroimage.\n\nBut if seeing someone yawn doesn’t activate these centers, what does it do to the brain? The researchers found that it appears to strongly activate at least one brain area, called the superior temporal sulcus. But this activation was unrelated to any desire to yawn in response, so it may be irrelevant to the contagion question, the researchers added.\n\nPossibly more significant, they wrote, was the apparent deactivation of a second brain area, called the left periamygdalar region. The more strongly a participant reported wanting to yawn in response to another person’s yawn, the stronger was this deactivation. \n\n“This finding represents the first known neurophysiological signature of perceived yawn contagiousness,” the researchers wrote.\n\nExactly what the finding means is less clear, they acknowledged. The periamygdalar region is a zone that lies alongside the amygdala, an almond-shaped structure deep in the brain in the area of the side of the head. The periamygdalar region has been linked to the unconscious analysis of emotional expressions in faces. Why it would be deactivated in tandem with yawn contagion is unclear, the researchers said.\nFurther details can be had from the site.\nVR
289289
Between 40 and 60% of the population is susceptible to contagious yawns, but the reason why yawns are catching is unknown.\n\nI yawned once when typing up this answer.
604697
lolol...yawns are contagious..u just made me yawn reading ur question...brat!!!
198710
When you yawn, you are attempting to take in as much air as possible, more oxygen gives more energy.  People in the immediate area are in competition for this air too and yawn as a response to retrieve air themselves
292528
Yawns usually occur because you have some lack of oxygen, usually when you are growing sleeping and not breathing properly. When a person yawms next to you, you usually stop breathing yourself, thus triggering a "contagious yawn." Need to prove this false? Next time you see someone yawn, be concious of it and make yourself take a deep breath. You wont get that contagious yawn!