It's true: dogs move their "eyebrows," but they do not necessarily use their eyebrows to convey the exact same emotions that humans attempt to communicate.
When it comes to communicating emotions, dogs are much more down to earth.
Their body language and associated emotions tend to be much more simplistic compared to the more sophisticated complexities of the human mind.
Stanley Coren claims that dogs feel basic emotions such as fear, anger, happiness and surprise, but more complex emotional states appear to escape them.
Complex emotions such as guilt, pride and shame don’t really seem to exist in a dog’s world. Perhaps that explains why dogs don't mind to sniff butts and pee on rugs.
However basic, understanding dogs at a deep level requires very close observations and a careful assessment of the context in which their behaviors occur.
A dog moving the "eyebrows" may occur in various circumstances, and until the day dogs can talk, we can only speculate on what they are truly feeling or trying to express. In the meanwhile, some studies may provide some food for thought.
First Off, Do Dogs Have Eyebrows?
By definition, eyebrows are two arched areas above the eyes composed by hairs. In humans, Mother Nature has gifted humans with eyebrows for a variety of functions.
One main function of eyebrows is to prevent sweat from your forehead from trickling down into your eyes, similarly to how gutters deflect drops of rain away from your home. On top of preventing sweat, eyebrows also prevent dandruff from falling inside the eyes. .
Another important function of eyebrows is to work as communicative tools. Humans rely a whole lot on their eyes as means of communication. Eyebrows may be raised to communicate curiosity, while lowering of the eyebrows may communicate anger.
Now, dogs do not sweat as humans do. While humans have a large amount of sweat glands distributed over their bodies, most of a dog's sweat glands are found on their paws. This is because unlike humans, dogs cool themselves down through panting rather than sweating.
On top of this, dogs do not use their eyes as means of communication, at least not to the extent that humans do. Humans are believed to have large areas of white around the eyes (the sclera) and the capability of crying and moving their eyebrows (which by the way, are in high contrast with the skin) primarily because the eyes play such an important role in non-verbal communication.
To put it simply, humans rely a whole lot in looking in each other's eyes.
Among dogs instead, steady direct eye contact among each other could potentially stir trouble. This may possibly explain why a dog's sclera is reduced to just a narrow rim, making their eyes considerably less conspicuous compared to humans.
However, things may be different when it comes to a dog's communication with humans. After years or domestication, dogs make eye contact with humans and seem to be even eager to do so, especially if they have been conditioned to understand that making eye contact with humans is a good thing after all.
Special "Eyebrows" in Dogs
Dogs do not have eyebrows as humans do, and most likely it's because they don't need them to the extent that humans do. However, some dogs have special pigmented markings over their eyes and these are sometimes referred to as "eyebrows."
Breeds of dogs with distinct markings over their eyes include Rottweilers, German shepherds, Bernese mountain dogs, Doberman pinschers, Gordon setters, miniature pinschers, English toy spaniels and the black and tan coonhound just to name a few.
Some other dogs may have a pattern of fur that produces a shadow or other types of markings that delineate the area above the eyes. Schnauzers in particular, are known to have lots of hair over their eyebrows along with lots of facial hair (beards and mustaches).
While visible eyebrows under the form of markings or hairs over the eyes are only seen in a few dog breeds, something that all dogs have in common are special whiskers over the dog's eyes that are known as "supraorbital whiskers."
These whiskers are also sometimes referred to as "eyebrows" by some dog owners.
In this article, the term "eyebrow" will be used to simply refer to the skin over the ridges formed above the eyes, regardless of whether the area is hairy or pigmented.
These "eyebrows," regardless of how they present, can help accentuate the movements of the muscles above the dog's eyes. So the next question is: why do dogs move their eyebrows?
Why Do Dogs Move Their "Eyebrows?"
Dog may move their "eyebrows" when they are moving their eyes in different directions. They are also frequently moved in their interactions with their owners and humans in general.
Stanley Coren in the book "How To Speak Dog: Mastering the Art of Dog-Human Communication" claims that dogs move their eyebrows to communicate emotions such as perplexity and concentration, anger and fear.
Interestingly, it appears that dogs move their the muscles above the eyes specifically for a human audience.
According to a study conducted by Julian Kaminski, dogs appear to exhibit more facial movements when humans are facing them compared to when when they are turned away.
In particular, dogs were likely to raise their inner "eyebrow" and show out their tongues. They were also more likely to vocalize in presence of humans as well.
Previous research by Waller et al. had found that upper facial muscle contractions in dogs caused dogs to raise their eyebrows, causing their eyes to appear bigger and more infant-like. Large eyes in puppies and dogs have been associated with cuteness which pulls at any dog lover's heartstrings.
The research indeed showed that, the more often dogs made facial movements that resulted in raising their inner eyebrows, the quicker dogs were rehomed.
This makes one wonder whether dogs have learned to use their facial expressions as a way of getting what they want (human attention) or whether this is just a trait that dogs have been selectively bred for throughout the years.
Did you know? Research by Nagasawa et al revealed that upon noticing the owner's arrival, dogs moved their left eyebrows for about half a second, suggesting a positive social emotion. They failed to move their eyebrows though in response to attractive toys or when strangers greeted the dog.