Part 2, Human-Animal Pack Dynamics
In Part I, we considered some of the possible physiological and behavioral effects of domestication, with the most critical relative to the practice of holistic veterinary medicine being the awareness that this represents an on-going, multi-factoral, integrated body-mind function. A change in some physiological parameter as the result of human interaction or intervention, nutrition, disease, or injury will alter an animal’s behavior, just altering an animal’s behavior will give rise to physiological changes. Although the idea of taking an integrated body-mind approach to the treatment process still remains anathema in much of western medical education, such an approach may provide new insights into old problems as well as result in more comprehensive treatment regimes.
In addition to the physiological and behavioral legacy endowed by domestication, animals also manifest that which results from their relationships with others in their environment. In the most general of terms, animals which prefer to live in groups are referred to as social, compared to solitary animals which spend much of their time alone. However, as with everything in nature, no fixed linear either/or spectrum exists. Members of some social species may naturally experience periods of solitude (such as when sexually mature males strike out to seek mates and/or establish their own territories and groups), and normally solitary species may form highly complex social structures during the mating season or when a reliable food source exists in a limited space. Within the domestic arena, all animals except for the cat are considered social.
When social animals relate to people, most do so using a basic repertoire of behaviors that evolved to facilitate energy-efficient communication among their conspecifics (i.e., their own kind). Additionally domestic animals will adapt pre-existing intraspecific behaviors to meet the unique needs of human-canine interaction. For example, wild dogs will display a submissive grimace in which they pull their lips back and upward at the corners to expose their teeth at the same time they hold their heads lowered and turned to one side with their ears back and eyes slightly closed. Because such displays evolved to avert a confrontation, typically this display causes the animal toward which the display is aimed to terminate the interaction. Compare this to what happens in the human-animal arena where humans who see this display in their pets may interpret that grimace as a smile and reward it with laughter, praise, treats, walks, or access to otherwise forbidden furniture whenever the dog displays it. In such a manner, a display that serves to signal of inferior rank and terminate interaction in the canine pack becomes one which the pet uses to manipulate the owner for its own gains.
Traditionally ethologists referred to the structure that resulted from the interactions of members of a group as a dominance hierarchy. However, over time it became clear that this terminology elicited erroneous images of a rigid rank order with some “top dog” lording over a linear progression of ever more subordinate animals, the least of which lived a hellish life in which it was picked on by everyone. Because of this, many ethologists now refer to the structure of social interactions as dominance relationships because this more accurately reflects their dynamic integrated rather than fixed linear nature. The leader of the pack may eat first or mate more often, but maybe not. While at one time or another, everyone in the group may elicit a subordinate response from one particular member, that animal isn’t constantly bullied by everyone.
At this point it would be advantageous to note that pack leaders generally are the most aggressive animals in the group. Unfortunately, this can’t be done because the scientific community has opted to equate aggression with hostility rather than responsiveness, the more behaviorally meaningful definition favored by old-time bird-dog trainers. The latter individuals evaluated potential canine candidates using a triune of intelligence, aggression, and mouthiness. Based on this, the ideal dog learns quickly, readily notices and responds to changes in the environment, and has a “soft” mouth, i.e., it will hold, but not crush a bird. Using this criteria, we can see how a good herding candidate would be intelligent, aggressive, and with a slightly harder, nipping mouth, whereas a good fighting dog would exhibit intelligence, aggression, and an willingness to clamp its jaws tightly.
In addition to equating aggression with hostility denying us a very valuable criteria for evaluating behavior, it creates the erroneous impression that all aggressive displays are, or signal impending, hard-mouthed ones. When we couple this with the erroneous belief that pack leaders invariably fight their way to the top, we wind up with a lot of biting dogs wearing the label “dominance aggressive” when, in fact, nothing could be further from the truth. In reality, evolution tends to favor those who can gain and hold resources without engaging in actual fights. Because fighting requires a great expenditure of energy and risks injury, an animal which can get another to yield by more subtle gestures will have more energy to devote to other more evolutionarily consequential activities such as mating and reproduction. Hence, its genes more likely will make it into the gene pool than those of the fighter.
Within a social group, how much stress an animal experiences doesn’t depend nearly so much on its position as it does on the stability of the pack as a whole. As long as an animal knows its place and receives consistent cues from others to confirm it, even the most submissive animal can live a fairly stable life. On the other hand, many times human-canine packs offer no such stability. Some preliminary studies by József Topál and Adam Miklósi and others suggest that dogs lean toward viewing humans more as parents than peers. This makes sense because humans most commonly enter the dog’s life when the animal is quite young. Unfortunately, though, the idea of a dog being a human’s “best friend” leads many people to knowingly or unknowingly relate to their dogs as litter mates rather than as good parents. Although such a democratic approach may strike us as spiritually valid, it’s not without its problems for the dog. Trying to lead a pack of humans with bigger brains, opposable thumbs, and hectic lifestyles may overwhelm those animals whose early experiences with litter mates primed it to assume a more subordinate position. (Pack structure in dogs emerges on day one when the more aggressive/responsive animals claim the most readily accessible teats and the least wind up nursing those in the inguinal region. Hence the expression, “Sucking hind tit.”) However, even the most naturally dominant animal may find riding herd on a busy owner in a complex environment overwhelming.
When evaluating human-canine pack structure, a convenient rule of thumb is to use the mantra, “Leaders initiate, followers react.” In a human-centered pack, the humans spend more of their time initiating interactions with the dog that reacting to it. In a dog-centered pack, just the opposite holds true; the dog does most of the initiating. If the dog experiences no chronic or recurrent medical, behavioral, or bond problems, the fact that the owner assumes a subordinate role is inconsequential. However, if such problems exist, then a change in the human-canine pack structure could benefit both owner and pet a great deal.
But exactly how does pack structure affect an animal physically? Studies in wild animals as diverse as fish, mice, and insects indicate that a shift in status may alter an animal’s physiology dramatically. This occurs because, once an animal expends the necessary energy to prove its worth, it’s energy-efficient to have some means to signal this to others so these displays needn’t be repeated every time. A comparable situation in humans takes the form of the various insignia and titles used to communicate rank within military, academic, and corporate cultures. Normally those of lesser rank will defer to those with a higher rank unless they believe they have a reasonable probability of usurping that individual’s position.
Among the insignia worn by members of the animal kingdom we find a leader pheromone package that communicates rank by scent and/or changes in coloration that provide visual cues. In the human-canine pack, signals of high canine rank may include access to prime sleeping locations (such as the owner’s bed), charging through doors ahead of the owner, food-related aggression, jumping up, leaning, nudging, whining, barking, and other displays used to secure the owner’s attention. As with all forms of animal communication, the meaning of the display may vary depending on the context in which it occurs. Interestingly, many owners will interpret these signals of canine leadership as signaling their pets’ love.
Internally, long-term studies of olive baboons in Kenya by Robert Sapolsky indicate that marked differences in adrenocortical and gonadal function, autonomic and immune profiles, cholesterol metabolism, cardiovasular responsivity, and insulin-like growth factor may exist between high- and low-ranking individuals. Add Adam Miklósi’s studies which suggest that some aspects of canine interactions with humans appear more closely related to that of higher primates than wild canids, and Sapolsky’s findings become even more intriguing, not only for what they tell us about our dogs, but also for what they tell us about ourselves.
Hopefully at some time in the future we will have similar studies of physiology as a function of conspecific pack structure, at least in our most domesticated species, the dog. However, that’s not as easy at it may seem. It seems likely that litter, line, and breed factors will yield different values for these parameters just as thyroid levels may vary. Additionally, as previously noted, rank isn’t fixed; lower ranking animals may move up as older ones die or are replaced by others.
Even more important, though, we can’t overlook the ways human-canine pack structures may differ from strictly canine ones. Many human-canine packs exist in which humans deliberately or inadvertently assign leader rank to dogs whose temperament would never cause them to assume this position among their conspecifics, humans, or both.
For a glimpse of what might possibly happen under these circumstances, consider this common human-canine pack scenario. Krispie comes into the household programmed to relate to the owners either as he did to his mother or other adult animal with good parental skills or his litter maters, with the former being the more beneficial choice. However, the owners gush over him and automatically talk to him in a higher pitched sing-songy tone of voice, more reminiscent of the whimpering of a submissive pup than the tones of a responsible parent. If the owners allow him to jump up on them, charge through doors ahead of them, drag them down the street, and otherwise claim the privileges of higher rank, this will further cement his position.
Pups at both ends of the dominance and subordinate spectrum thrust into this role may respond more aggressively to perceived threats from the beginning. However, many dogs don’t assume the leader role until they become mature. Depending on the breed and individual, this may occur as early as 6 months or as late as 2 years of age. Or it may not show up until an existing leader dog in the household dies or moves out. Some owners notice a gradual change in their dog’s behavior-such as its adding lunging and snapping to the barking at the letter carrier over a period of months. Other times, the shift occurs so rapidly the owners believe some horrible disease or injury befell the pet and triggered the behavioral change that day.
When a more naturally submissive animal gets thrust into a leadership position, it will react far more hostilely than a more confident one because it lacks both the behavioral and physiological wherewithal to function in this role. Consequently the “get them before they get me” mode presents the most logical survival strategy. Compare this to the response of the more confident leader animal who may stand back and stare at the letter carrier, then curl its upper lip, then growl as part of its energy-conserving body language designed to prevent a fight. Then compare both of these leader dogs to the dog of any temperament who lives in a human-led pack. Rather than feeling obligated to initiate a response to any perceived threat, that dog looks to its owners for cues and reacts accordingly: If the owner is happy to see the letter carrier, so is the dog.
When an animal with an inherent physiological and behavioral pattern for subordination in the human-canine pack must muster the wherewithal to express leadership, what does this do to its physiology? Alas, here again we don’t know. However, it seems to reasonable to hypothesize that this, too, would affect adrenocortical and gonadal function, autonomic and immune profiles, cholesterol metabolism, cardiovasular responsiveness, and insulin-like growth factor metabolism. Moreover, whereas a subordinate wild social animal would rarely, if ever, need to confront any threats alone and most threats handled by the pack would be relatively few and of short-duration, the average canine house-pet left home alone may experience the physiological and behavior effects of its aberrant social structure on a daily basis. Over a period of time, it doesn’t seem unlikely that this would take its toll on the animal’s health.
References:
Campbell, William E. Behavior Problems in Dogs, 3rd Edition. (BehaviorRx Systems, 1999)
Grier, James W. and Burk, Theodore. Biology of Animal Behavior. (Mosby, 1992)
Sapolsky, Robert. “Endocrinology alfresco: psychoendrocrine studies of wild baboons.” Recent Progress in Hormonal Research. 48:437-453, 1993.
Sapolsky, Robert, and Spencer, Martin. “Insulin-like growth factor I is suppressed in socially subordinate male baboons.” American Journal of Physiology-Regulatory, Integrative, and Comparative Physiology. 273:R1346-1351, 1997.
Topál, József, Miklósi, Adam, et al. “Attachment behavior in dogs.” Journal of Comparative Physiology. 112:219-225. 1998.