Like
many of us,
you probably think that people yawn when they are hungry or tired.
Actually, this is not exactly true! After many studies, all
scientists do not explain this phenomena the same way.
A whole family happily yawning together
Yawn
to make our brain colder
One
of those theories is the one of Dean Falk, an anthropologist. He
think that we yawn for make our brain colder. Indeed, when we are
tired our brain is warmer than its...
