You, like most Americans, probably plan to run for president. You have plenty of time, theoretically; the general election is still 22 months away and even if you plan to seek the nomination of one of the major parties, those don't kick off until January.
Rearing is a common measure of activity and exploratory behavior used in the open field and sometimes in certain mazes. Nothing else. But I agree it could be related to very specific behaviors. I like the idea of escape.
rear. n. 1. the back or hind part. 2. the area or position that lies at the back: a garden at the rear of the house. 3. (Military) the section of a military force or procession farthest from the front. 4. the buttocks. See buttock.