The Language of Wag: What Your Dog is Really Saying


The classic telltale sign of the emotional state of man’s best friend is the position and movement of the tail. Wagging infers happiness or excitement, while the well known “tail between the legs” demonstrates fear, shame, or timidity. But the action of your dog’s tail and their behavior is spectacularly more complex than this. Veterinarians and dog researchers worldwide have done profoundly in-depth studies on your furry friend’s brain and behavior. A surprising recent discovery is that tail-wagging can actually indicate aggression depending on which way the tail sways. Experts have documented that tail wagging favoring the right side of a dog’s body in slightly circular motions signifies amiability while left-sided wags indicate aggression and anxiety. In this groundbreaking study, Italian veterinarians tested dog interactions with their owners, other dogs, human strangers, and cats. Not surprising, owners elicited a strong right bias or amiable response, while smaller dogs and human strangers elicited a weak right bias or less amiable response. Interactions with cats provoked a strong left-sided or aggressive tail wagging response.

So what to make of these mysterious findings? Scientists predict that the answer lies in the neurological structure within the dog’s brain. Similar to humans, dogs possess two separate sides of the brain which become excited during different emotional states. Left-sided brain emotions include love, affection, bonding, and security while aggression and anxiety are known as right-sided emotions. The physical, real life response, is, however, exhibited opposite to the excited side of the brain. So affection is an emotion felt in the left side of the brain, but is acted out on the ride side of the body. This explains why a puppy happy to see its owner will wag its tail more toward its right side.

Dog’s are expressive animals and so are humans. This is why we so closely identify with them and often develop such extremely close bonds with them. Tail wagging says a lot about a dog’s emotional state and there are a number of factors you should keep in mind when trying to read their state of mind besides the left-right bias.

If something has caught your dog’s attention and he or she becomes aroused, expect the tail to be high and stiff. This is a classic sign that your dog may be in an aggressive state of mind. A stranger at the door, mailman, or malevolent cat may cause this rigidity in the tail. Also known as flagging, the dog may slowly wag the stiff tail while still pointing it upward. On the other hand, timidity and submissiveness will result in tail tucking under the buttocks and firmly against the stomach. These emotions are often detected during thunderstorms or trips to the vet. It’s important to keep in mind that dogs, like humans, have unique responses to emotional stimuli. Tail wagging may be a convenient way to detect the emotional state of your furry friend, but always know that doggy behavior is anything but simple.