Dogs Show 'Sad Puppy Face' More Often When Being Watched

Dogs change their facial expressions when they know people are looking at them--perhaps in an effort to communicate. For instance, canines in the study would make the classic "sad puppy face"--raising their inner eyebrows to make their eyes look larger and more infant-like--when looking into a human's eyes. The discovery adds to scientists' ever-growing understanding of man's best friend, one of our species's longest companions. Humans and dogs have lived side by side by some 30,000 years, and along the way, evolution seems to have sculpted dogs' behavior. Research has shown that dogs constantly monitor humans, intently watch our gestures, and in comparison to hand-reared wolf puppies, tend to look up at human faces more often.