Why do we yawn?

SSSnail

Lifer
Nov 29, 2006
17,458
83
86
And why is it so contagious? When you see someone yawn, you have the urge to yawn too. Reading about it could have the same affect. Now, yawning could be intepreted as being bored, tired, sleepy or simply sympathizing with the person you're speaking to.

So, why do we yawn? Why do YOU yawn? Are you yawning at this thread yet? Or are you just simply yawning because you just read about it? :p
 

loic2003

Diamond Member
Sep 14, 2003
3,844
0
0
Yawning is when you're low on oxygen and your body needs a bit more. It's also caused by hormones/chemiacs in your body when you're tired I think.

it is thought to be contageous from our days in caves to trigger the thought that was are all tired together and so would sleep at similar times, ie helps us live as a pack/herd instinct.

That's all I know. Try google.
 

shortylickens

No Lifer
Jul 15, 2003
80,287
17,082
136
I was gonna wikpedia bash but instead I'll just go with:
"it gets oxygen into the body for a change in metabolism".
 

shortylickens

No Lifer
Jul 15, 2003
80,287
17,082
136
Originally posted by: Scouzer
Note that the oxygen thing is a theory, and it has been contested.
As is gravity.
Do you actually have a point here?

EDIT: Sorry, didnt want to sound mean or angry.
I was just wondering exactly what you were getting at.
I need to work on being extra nice first thing in the morning.
 

Scouzer

Lifer
Jun 3, 2001
10,358
5
0
Originally posted by: shortylickens
Originally posted by: Scouzer
Note that the oxygen thing is a theory, and it has been contested.
As is gravity.
Do you actually have a point here?

EDIT: Sorry, didnt want to sound mean or angry.
I was just wondering exactly what you were getting at.
I need to work on being extra nice first thing in the morning.

I mean, there are many other theories existing so I don't think the oxygen theory should be spouted as fact.

The point being, it is not a fact, it is just a guess.
 

SSSnail

Lifer
Nov 29, 2006
17,458
83
86
Originally posted by: Chrono
damn you. learn to use google you bastard.
That's not the point of ATOT is it? I can wiki or google all day, but dzey don't do nothing. :p

/yawn...
 

FoBoT

No Lifer
Apr 30, 2001
63,084
15
81
fobot.com
it is to expel excess carbon dioxide from your lungs

each time you breath, only a portion of the gases in your lungs are exchanged

a yawn (deeper breath) changes out a larger % of the gases in your lungs than normal respiration
 

SSSnail

Lifer
Nov 29, 2006
17,458
83
86
So everytime you yawn, it's because you want to expel excess carbon dioxide? Shens.