the poop happens world we live in thread 2XXX

[Chutzpar]

Seeing as you yawn when
a) you're tired
b) you need oxygen
and i'm not tired, well

yawning actually isn't really understood that well; a lot of the theories are based on conjecture and circular logic, afaik.
Also:

Robert Provine, a developmental neuroscientist at the University of Maryland [...] has tested this theory: Giving people additional oxygen didn't decrease yawning, and decreasing the amount of carbon dioxide in a subject's environment also didn't prevent yawning