Need a pick-me-up today? Watch a video of a smiling dog – it should do the trick. But is your dog really "smiling" in the way humans understand it? And if so, what is it trying to communicate?

Need a pick-me-up today? Watch a video of a smiling dog – it should do the trick. Any dog can smile, and according to veterinary behavior specialist Dr. Lore Haug, some breeds are even genetically ...