Muzzle licking was consistently done by subordinate dogs to individuals of higher rank and was highly predictive of relationships between individuals. The clearest signals were those associated with voluntary submission, or deference. Trisko observed that dominance relationships were not about coercion, force or fighting, but rather, about an understanding by both individuals of their relative social status.
In another study exploring dominance relationships between dogs, Simona Cafazzo and three colleagues observed a group of feral dogs in the suburbs of Rome. Their primary finding was that the dogs formed a linear dominance hierarchy, meaning that the individuals in the group could be ranked in order from highest to lowest in status. (Other possible social structures include having one individual who dominates all others who are equally low-ranking or societies in which the relationships are not transitive— e.g. A dominates B, B dominates C, C dominates A). A linear dominance hierarchy indicates that the dogs in this study were capable of forming stable social groups, although many have claimed that feral dogs cannot do so. Additionally, they found that submissive behavior was most predictive of dominance relationships, rank correlated with age, and males within an age class outranked females. Rank order in the linear dominance hierarchy predicted access to food resources, with those of higher rank having priority access.
Dominance has been studied in puppies as well as in adult dogs. John Bradshaw and Helen Nott reported that interactions between littermates were inconsistent over time, and that observations of such interactions did not predict which puppy would come out on top in any competitive situation; “winners” varied from one day to the next. Despite much discussion of choosing (or avoiding) the dominant puppy in a litter, interactions between littermates do not reveal dominance relationships, much less any kind of linear hierarchy.
The Dangers of Misunderstanding Dominance
Conversations about dominance relationships between dogs are often tense, but discussions of the concept within the context of relationships between humans and dogs are sometimes nothing short of explosive. Many of the strongest objections stem from using it to endorse force-based, coercive styles of training. According to Trisko, “Dominance has been wrongly equated with aggression and used to rationalize the use of physical force and intimidation by humans toward dogs. Misunderstandings of the concept of dominance have led to unnecessary physical punishments and abuse of dogs by humans.”
While no studies have thoroughly investigated whether dominance relationships exist between people and dogs, there is evidence that such training styles can create problems. Herron et al. investigated such techniques, often called “dominance reduction training,” and found them to be counterproductive. The confrontational methods associated with training styles that insist that we “get dominance over our dogs” caused aggressive responses in 25 percent of the dogs in their study. Techniques such as grabbing a dog by the jowls and shaking; hitting or kicking; staring; performing alpha rolls (also called “dominance downs”) and physically forcing a dog to release an item were more likely to result in aggressive behavior than were gentler, positive methods. Using such forceful methods can actually create problem behavior as well as increase a dog’s fear and anxiety. Based on what we know about dominance relationships between dogs, this is not surprising. As Trisko notes, “If dominance relationships between dogs and humans are at all similar to dominance relationships between dogs, then dominance does not apply to all relationships and when it does apply, it does not require the use of intimidation or physical force.”
A basic ethological premise is that we must understand the animals we study. In fact, this principle is considered so absolute that it is most often phrased as a commandment: Know thy animal! Understanding how social dominance does and does not apply to dogs is part of knowing who dogs are. Trisko makes this point: “If we really want to understand our dogs’ behavior, especially their relationships with other dogs, ignoring dominance will hinder us.” Bekoff agrees. “That’s who they are, that’s how they behave. They form status relationships, and we have to understand that.”