Yawning behavior

The above raccoon, not raccoon dog, is yawning.

And we observed that the raccoon dog yawned.

So we make three hypothesis about why the raccoon dogs yawn.

Before we observed yawn of the raccoon dog, it had aten a can tuna.

So we thought it could be a drowsiness after meal ("식곤증").

By comparing the frequency of yawn before and after meal,

we can prove this hypothesis.

When you yawn, you may think that you are sleepy.

So we make the second hypothesis that the raccoon dogs yawn to refresh their brain.

We can prove it by comparing the yawn frequency following the ration of oxygen.

Less oxygen may cause more yawns.

The baboon yawn to threat enemy.

It is possible to raccoon dog also; the yawning of raccoon dog is sign of warning.

If we compare the frequency of yawns with and without human watching,

we can prove this hypothesis.