One of the cutest things is when you catch a hamster waking up, stretching out and letting out a big yawn.
They will often do this after a short nap, widening their jaws as wide as they can and stretching out their limbs. Just like we do in fact.
Many different animals do it, from cats and dogs to rats and fish. Even human babies yawn in the womb
So why do hamsters yawn?
No nobody knows for sure but here are some theories and observations
Cooling brain temperature
A 2007 study by Andrew Gallup a psychology professor at SUNY College at Oneonta suggested that yawning may serve as a thermoregulatory mechanism.
Steven Platek, a psychology professor at Georgia Gwinnett College, comments
“In studies of mice, an increase in brain temperature was found to precede yawning. Once the tiny rodents opened wide and inhaled, the temperature decreased. “That’s pretty much the nail in the coffin as far as the function of yawning being a brain cooling mechanism, as opposed to a mechanism for increasing oxygen in the blood," says Platek. (source: Smithsonian)
A sign of contentment
Many owners comment that yawning is a way of communicating contentment. If they are yawning it means that they are at peace and comfortable at that time. Anxiety is at a minimum and they are able to relax.
Ready to sleep
Often they will yawn before they are ready to go to sleep or even go back to sleep if they have just woken up, so the theories of yawning to cool the brain down and getting to relaxed state back this up.
So if you see your hamster yawning, there is a reason for it and just like us, they are looking to lower the temperature in their brain so they feel relaxed enough to sleep.