When I get home, there's no question in my mind that my pups are excited to see me. And they each have their own way of expressing that joy. Scuttle runs in circles and wiggles her whole body uncontrollably, while Nemo barks and wags his tail. While these behaviors are often thought of as the sign of a happy dog, a new study shows that canine emotions may be more universally expressed through their eyebrows and ears.
Researchers at Japan's Azabu University used high-speed cameras to track dogs' facial movements  in response to different stimuli. They found that dogs tended to move their eyebrows up, particularly on the left side, when seeing a human family member and moved their left ear back when meeting a new person. If the pups were shown an object they had a bad association with, like a pair of nail clippers, the dogs moved their right ear instead.
One of the scientists, Dr. Miho Nagasawa, hypothesizes that the ear movement in response to unfamiliar or negative things may stem from its use to convey emotional expression. Eyebrow movement may reflect the movement to look at someone that they have an established relationship with.
After reading about this study, I tried watching my dogs when I came home yesterday. As you can imagine, excited pups move way too quickly to see eyebrow movement! However, I am really curious about the range of facial expressions to different people. For instance, Scuttle loves people and when we meet a stranger, she can barely control her excitement. Would her facial expression be radically different with me versus with another person? I would really like to see more research done on the canine facial expressions associated with established human relationships.
What are your dog's happy signals?