Understanding How Dogs Communicate

ogs are considerably more proficient at reading us than we are at reading them. Twenty thousand years of close contact with humans have made domesticated dogs the only animal species that can reliably interpret human intent and emotions through scent, tone of voice, gesture and body language. 

Human beings are highly dependent on verbal communication. Unless you are a communication expert or a psychologist, you are probably not better at reading people than at reading dogs.

Humanizing dogs

Many people make the mistake of “humanizing” dogs by attributing emotions, attitudes, and views typical to humans. The scientific term is anthropomorphism. A typical example can be seen in thousands of videos where owners capture their dogs feeling “guilty” after causing havoc in the house in their absence. Guilt is an unknown emotion to dogs, the look in question is only a submissive posture that indicates a mild degree of fear in anticipation of being scolded, triggered by hearing a change in our tone of voice and body language.

We make many mistakes when trying to interpret dog behaviors. We misunderstand their motivations, we punish them unfairly when they cannot possibly understand, we communicate the wrong messages and give the wrong clues, we fail to anticipate their reactions, and in doing so, we sometimes put ourselves at risk of being bitten.

How dogs perceive us

Dogs can sense a person's tension, fear, and anxiety. Many dogs have been observed mirroring the emotions of their owner as their own, and can show psychological distress if someone close is unwell or depressed.

Smell is the primary sense in dogs, and by far the most developed. Nonverbal communication between dogs primarily happens through scent and is mediated by chemicals that dogs detect called pheromones that inform on sexual and social clues. 

Italian scientists from the University of Naples have demonstrated that dogs also pick up on olfactory cues from humans and can smell fear and other emotional states.

Vision is used to interpret human body language and gestures. Dogs follow our gaze, and can understand intent through our gestures and our posture. Most of this happens without our awareness.

To a lesser degree, dogs are also sensitive to the sounds we make. What they decode is our tone of voice to interpret or consolidate the information they perceive regarding our emotional state. Dogs can learn to recognize and memorize the sounds of simple words simply by tone.

How dogs communicate

The most reliable and easiest way to understand a dog’s state of mind, and more importantly his state of arousal, is through the observation of his body language.

Dogs use body posture, ears, tail, mouth, and gaze to express how they feel. Some dogs are more reactive and expressive than others, and there are differences between breeds.

The most revealing sign of a dog's emotional state is body posture, and it's also the most reliable because the shapes of the ears and tail can vary greatly between breeds. The subtle changes in the floppy ears of a Beagle or the curly tail of a Malamute can be difficult to read.

The following image, taken from the remarkable book "The Dog's Mind, Understanding Your Dog's Behavior" from British Veterinarian Bruce Fogle, shows the different states of arousal in dogs and their corresponding body language.

On the left the dog goes from calm and alert to aggressive, on the right, from calm to fearful and submissive.

A dog's body posture can change gradually or with little warning, and can show signs that the dog is either calm, happy, excited, nervous, fearful of cautious. The two opposite behaviors illustrated above are aggressive dominance and submissive behavior. 

Aggression can escalate in 4 stages of postures:

1. Calm: ears and tail relaxed, mouth closed or slightly open 
2. Alert: with ears and tail up, mouth close tight or lips trembling 
3. Menacing: hackles up, tail up, rump up, lips pulled back
4. Aggressive: snarl with teeth exposed, and forward straight stance

Aggressive dog behaviors

In the wild, feral dogs —or village dogs—are seldom observed to be aggressive toward humans unless provoked. Aggression between dogs is rare and usually limited to a rivalry between packs. Each dog pack has a well-defined hierarchy with leadership and social rules, and dogs make use of plenty of warning signals that make fights a rare occurrence.

In pet dogs, aggressive displays often occur when dogs are on a leash. Dogs are extremely perceptive of our emotions, and our state of mind is transmitted through the leash. Reactive demonstrations of defensiveness or dominance toward other dogs are often due to a lack of leadership or confidence on the part of the owner, and is more frequent in herding breeds such as German shepherds and Rottweilers with a strong defense drive. Reactive dogs can become protective or dominant when they sense their handler's fear or anxiety through smell, or when they sense nervousness through leash tension.

Aggression toward humans is relatively rare because dogs give warning signals before acting up. The rate of deaths from dog bites is very low, with only 8 per million dog bite fatalities. You are 1,000 times more likely to get killed in a car accident, and 350 times as likely to get killed by firearm as to be killed by a dog. We also know that 70% of bites happen to children under the age of ten, which is an age when children are unable to interpret a dog’s aggressive warning signals.

A fearful dog can adopt a posture that can be initially misinterpreted as submissive —with ears pulled back, head and tail down, body slightly hunched leaning back— and can become menacing and aggressive if the dog feels that he has no other choice than to fight. Dog aggression toward humans is far more often motivated by fear than by dominance.

A dog wagging his tail does not necessarily mean that he is happy. Dogs can also wag their tail if they feel nervous. Typically, a low-hung wagging tail can mean that the dog is fearful, a high and stiff wag can mean that the dog is nervous and might turn aggressive.

As you can see in the slow-motion video below, the Malamute shows a very dominant posture from the start of the encounter with the other dog. He is borderline aggressive, with the body leaning forward, the head down, a direct stare, erect tail and ears, and the mouth slightly trembling (a sign of nervousness). The Malamute goes into an aggressive mode without much warning. In this reactive and dominant dog, the aggression was triggered by the owner suddenly putting tension of the leash. The encounter should have been avoided at the first sign of the Malamute’s nervousness. The small dog was submissive, but like many pet dogs that are poorly socialized, he failed to pick up on the early warning signals from the Malamute. 

Some breeds (Malamutes, Akita and Rottweilers) are harder to read than other breeds, and can be highly reactive and unpredictable, with quick changes and few warning signals.

Barks and dog sounds

Dogs communicate through sounds for warning (growl, bark), eliciting (howl), or complaining (whine, wimper, yelp). Communication by sound is a canine trait that has been encouraged through selective breeding in guarding and herding dogs. Dogs are far more vocal than their wolf ancestors, and feral dogs are much less vocal than pet dogs.

Barking is often wrongly interpreted as a sign of aggression. It can indicate excitement or just be a warning or a vocal deterrent to keep strangers at bay. Barking becomes aggression if it's associated with snarling and teeth exposed, especially in dogs that are attached to a leash or locked inside a car.

Whining is a learned juvenile behavior observed in adult dogs that is only directed at humans to seek attention. You will rarely ever see an adult dog whining at another dog.

How to approach a dog

If you observe dogs meeting each other, you will notice that they always make brief eye contact and observe each other from a distance as they are approaching. Body language and energy are mutually evaluated, and smell follows sight for further information.

When meeting new dogs, humans —and especially children—have the dangerous habit of leaning toward the dog, often reaching forward to pet the dog without having been introduced. This can be confusing and threatening to the dog, and can lead to fearful or aggressive reactions with insecure dogs.

Meeting a new dog safely

• When meeting a new dog, let the dog come to you and smell you before you attempt to pet him, and be attentive of the dog’s body language.
• Do not make direct and persistent eye contact with a nervous dog if his body postures shows alertness or nervous arousal.
• Be mindful of your own body language if you sense that a dog his acting nervously. If you are uncomfortable around dogs, don’t look at the dog, or back away. Stay still, calm, and let the dog get to know you in his own time.
• Avoid talking to the dog until he seeks physical contact with you.
• Avoid petting dogs directly on top of the head, as this can be interpreted as a threatening gesture.
• Not all dogs like to be touched. Some breeds are notorious for being aloof, cautious, or easily spooked. Dogs that enjoy physical touch from strangers will elicit it.
• When letting your dog meet other dogs while walking on a leash, be mindful of the other dog’s body language before letting the encounter happen. In doubt, keep walking. If you let the dogs come close and smell each other, it is important not to interfere and to keep the leash loose with no tension to avoid giving your dog the wrong warning signals.
• Do not let children touch a dog without asking permission from the owner first. Teach children dog etiquette, and explain that all dogs are different, and that a dog's safe space should be respected.