how do yawns travel from one person to another?

[pulpp]

you know, someone starts yawning then all the sudden everyone else in the room starts yawning as well, is telepathic or psychological or just that contiguous?

 

[geno]

I dunno - but I yawned as soon as I read this title :Q

 

[adams]

I think that even looking at a picture of a yawn will make you yawn...

 

[ElPool]

when you yawn, it is to equalize the pressure inside your head and the pressure outside your head. of course, when you do this, it causes the pressure in the room to change, thus causing not-equal pressure in everyone else's heads, so they have to yawn too.

 

[adams]

In our distant past, when we lived and hunted in groups, every member of the group had a decent night's sleep. To ensure this happened, and there was no coming home late from the pub and waking up the neighbours, we all needed to go to sleep at the same time as each other. Yawning is a subconscious signal to others that we are tired and want to go to sleep and so they must do so too. This signal is particularly intended for the younger members of the group who persist in remaining active long after their bedtime. So remember, parents, next time Johnny is running around driving you mad, start yawning.

 

[pulpp]

wow, intresting facts...

 

[gittyup]

telepathic or psychological or just that contiguous?

I think it's just more visual.