Allow me to ANSWER ALLLLL your Questions (how come no-one knows this stuff).
a) We yawn when we are TIRED -- the extra oxygen and the expelling to stale old CO2 rich air helps to WAKE US UP. Thats why you yawn when you are tired.
b) The whole you yawn I yawn thing is due to humans being social animals. If one of our 'tribe' is tired (i.e. ANYONE else) then its probably time for sleep, yawning is a way of passing the message around (or so it is thought). Its kinda like when you see other people sleeping you want to go to sleep...
c) Based on answer a:
i) SIT UP -- give your lungs space to move
ii) Breath more deeply
iii) Get some fresh air and some light.
Ultimately, 'yawning is just a BIG breath of fresh air'. Thats also why you yawn when you get up in the morning.
Slashdot Mirror
Allow me to ANSWER ALLLLL your Questions (how come no-one knows this stuff). a) We yawn when we are TIRED -- the extra oxygen and the expelling to stale old CO2 rich air helps to WAKE US UP. Thats why you yawn when you are tired. b) The whole you yawn I yawn thing is due to humans being social animals. If one of our 'tribe' is tired (i.e. ANYONE else) then its probably time for sleep, yawning is a way of passing the message around (or so it is thought). Its kinda like when you see other people sleeping you want to go to sleep... c) Based on answer a: i) SIT UP -- give your lungs space to move ii) Breath more deeply iii) Get some fresh air and some light. Ultimately, 'yawning is just a BIG breath of fresh air'. Thats also why you yawn when you get up in the morning.