Scientifically, what its the purpose of yawning?

Answer 1

Hypothesized causes of yawning
A means of cooling the brain.
An action used as an unconscious communication of psychological decompression after a state of high alert.
A means of expressing powerful emotions like anger, apathy, apprehension, remorse or boredom.[citation needed]
An excess of carbon dioxide and lack of oxygen in the blood.
A way of displaying (or indicative of) apathy.
Tiredness

Excessive yawning has been associated with several medical conditions and may be considered as a medical sign for some diseases. These conditions include:
Multiple sclerosis
Amyotrophic lateral sclerosis (ALS)
Migraine headache (rare)
Radiation poisoning, including radiation therapy
Yawning may occur less frequently in persons with schizophrenia.

Answer 2

Purpose Of Yawning

Answer 3

Ok, so we yawn when we are bord, tierd or if we see someone else yawn. BUT yawning HAS actually got a very good purpose. We (including animals) 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. Certain aspects of yawning remain even more mysterious. Fetuses, for instances, have been observed yawning in the womb, yet it’s known that they don’t take oxygen in through their lungs. And yawning seems to be a symptom of multiple sclerosis and other medical conditions, for reasons unclear. Another puzzling phenomenon is that some male animals, men included, yawn in association with penile erection (although it’s presumptuous to assume they’re bored with their sex lives).

Answer 4

Get more air into the lungs and, indirectly, more oxygen to the brain.

It happens when you try to stay awake while your body tries to go to sleep (in sleep mode, organs need less oxygen).

It also happens when some parts of your body use up more oxygen, reducing the amount available to the brain. For example, when athletes resume the practice of a sport after a long break. Suddenly, the leg muscles (for example) have to work extra hard, using up most of the oxygen supply from the blood, leaving less for the brain. Athletes will yawn more often at the start of the season than near the end (with time, the body adjusts the manner it which it "oxygenates" itself)

Answer 5

This Site Might Help You.

RE:
Scientifically, what its the purpose of yawning?

Answer 6

There's no real answer, but there are a lot of theories. One is that we yawn to get more oxygen, another is that it's just stretching, and there are tons more.

Even though this website is for kids, it has a lot of information on it, and the results of a lot of experiments to find out why we yawn:
http://faculty.washington.edu/chudler/yawning.html

Answer 7

no-one really knows,some say that it originates from cave man days, it was a way of showing fellow cavemen you are tired and it was time to sleep. However some people say that it is to get a lot of oxygen into your lungs so u can get some more energy. Others say that it "cools" the brain if it overheats. Check out here for a full list: http://en.wikipedia.org/wiki/Yawn

Answer 8

Rids of excess carbon dioxide...

Answer 9

your lacking O2 to the brain

Answer 10

It gets in more oxygen.