If I don't throw the ball fast enough for my Lab mix Ace, he will bark as though he's frustrated. If I leave for a walk without him, I'm told Ace will sometimes whine as though he's sad or upset. When he's reunited with an old friend, he wiggles and wags with obvious happiness.Of course, it's easy to make assumptions about my dog's emotions. I don't actually know what he's experiencing. But if you…
