What is a mouse thinking?
Awake at three, running the wheel. Asleep whenever you are watching.
Mice are nocturnal and the wheel is not just exercise. Given one, a mouse will run several kilometres a night - wild mice will even use a wheel left outdoors, which suggests running is something they want to do rather than a captivity artefact.
The daytime sleeping is the same clock working normally. A mouse takes many short sleep bouts rather than one long one, which is why it always seems to be asleep exactly when you look in.
UncommonAround where it lives, but it takes a walk, a visit, or some luck.
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