* Fear and Adrenaline: Mice are naturally fearful creatures. When picked up, they experience a surge of adrenaline, which can cause them to tremble or shake. This is a common response to stress and fear.
* Muscle Tension: The fear and adrenaline can also cause their muscles to tense up, which might make them appear to be vibrating.
* Rapid Breathing: Mice breathe very quickly, and their small bodies can move a bit with each breath. This, combined with the trembling, might give the impression of vibration.
* Nervous System: The sudden change in position and the feeling of being held can also trigger their nervous system, causing minor tremors.
It's important to remember that while it might seem like vibration, it's more likely a combination of these factors, all resulting from the mouse's natural instinct to react to perceived danger.
