gravity and inter-sciurus relations

Sitting in the sun waiting for class to start. Coffee, bagel, iPod. Normality reigns.
Watching two squirrels in a tree. Without warning, one squirrel shoves the other one off the branch, whereupon it falls ten feet to the ground and lands on its back. Humilliated, it runs to the next tree, eight feet away, and climbs that one instead.
Then I went to class.