The old comic strip "Sylvia" once posited that if humans could understand cat language, they would find that felines actually make only two different statements: "Hurry that dinner, willya?" and "Everything here is mine."
Dogs, as any dog person knows, have a wider range of messages to transmit, which they do in all sorts of ways — barking, whining, tongue-lolling, mournful face-making, and of course tail-wagging. This latter means has attracted the interest of scientists in Italy, who put a lot of time into watching tails in action.
What they discovered is that dogs sometimes wag to the right and sometimes wag to the left. That may sound a confirmation of the obvious and meaningless, but the scientists concluded that the variation is not random.
The entire editorial is here.