squirells are much better problem solvers than dogs. I would consider them intelligent.
My dog once ran to the door barking loudly. When my Step-Dad got up to go see who was at the dorr, the dog turned tail the second the door was open. Ran back to the kitchen, jumped on the table, and ate half my step-dad's dinner. Consciously aware? I'd say that counts as a pre-meditated plan, and is fair evidence for consciousness.
Get 20 pet mice. name them all. get to know their individual personalities. Some are bold, some are not. Those who are bold tend to live longer in caged environments as their stress levels are significantly lower (not afraid of new expiriences).
I would say, yes, certain mice have more confidence than others.
See latest issue of Discover magazine for a synopsis of a study on this very topic.