12-hierarchy-obedience-resistance

A Twelve Hierarchy, Obedience, and Resistance t first glance, this chapter simply complements the previous one. Us/Them-ing is about relations between groups and our automatic tendency to favor in-groups over out-groups. Similarly, hierarchies are about a type of relations within groups, our automatic tendency to favor people close in rank to us over those who are distant. Other themes repeat as well—the appearance of these tendencies early in life and in other species, and the intertwined cognitive and affective underpinnings. Moreover, Us/Them categorization and hierarchical position interact. In one study subjects gave racial designations to pictures of racially ambiguous individuals; those dressed in low-status attire were more likely to be categorized as black, high-status attire, white.1 Thus, among these American subjects, Us/Them dichotomizing by race and the hierarchy of socioeconomic status overlap. But as we’ll see, hierarchy heads in different directions from Us/Them-ing, and in uniquely human ways: Like other hierarchical species, we have alpha individuals, but unlike most others, we occasionally get to choose them. Moreover, they often are not merely highest ranking but also “lead,” attempting to maximize this thing called the common good. Furthermore, individuals vie for leadership with differing visions of how best to attain that common good— political ideologies. And finally, we express obedience both to an authority and to the idea of Authority. F THE NATURE AND VARIETIES OF HIERARCHIES or starters, a hierarchy is a ranking system that formalizes unequal access to limited resources, ranging from meat to that nebulous thing called “prestige.” We begin by examining hierarchies in other species (with the proviso that not all social species have hierarchies). The textbook 1960s picture of hierarchies in other species was straightforward. A group forms a stable, linear hierarchy where the alpha individual dominates everyone, the beta individual dominates everyone except the alpha, gamma everyone except alpha and beta, and so on. Hierarchies establish a status quo by ritualizing inequalities. Two baboons encounter something good—say, a spot shaded from the sun. Without stable dominance relations, there’s a potentially injurious fight. Likewise over the figs in a fruiting tree an hour later, and for the chance to be groomed by someone after that, etc. Instead, fights rarely occur, and if a subordinate forgets his status, a “threat yawn”—a ritualistic display of canines—from the dominant male usually suffices.,2 Why have ranking systems? The answer, circa 1960s, was Marlin Perkins group selection, where a species benefits from a stable social system in which everyone knows their place. This view was fostered by the primatological belief that in a hierarchy the alpha individual (i.e., the one who gets first dibs on anything good) was in some manner a “leader” who does something useful for the group. This was emphasized by the Harvard primatologist Irven DeVore, who reported that among savanna baboons, the alpha male led the troop in each day’s direction of foraging, led communal hunts, defended everyone against lions, disciplined the kids, changed the lightbulbs, etc. This turned out to be nonsense. Alpha males don’t know which direction to go (given that they transfer into troops as adolescents). No one follows them anyway; instead everyone follows the old females, who do know. Hunts are disorganized free-for- alls. And an alpha male might face down a lion to protect a kid—if the kid is probably his own. Otherwise, he’d grab the safest spot. Male baboon giving a (hopefully) intimidating threat yawn. When viewed without Perkins-colored glasses, the benefits of hierarchy are individualistic. Interactions that proclaim the status quo obviously help the upper crust. Meanwhile, for subordinates, better to not get a shady spot than to not get it after receiving a canine slash. This is logical in a static, hereditary ranking system. In systems where ranks change, this caution must be balanced with occasionally challenging things—because the alpha male may be past his prime and getting by on bluff. This is a classic “pecking order” (a term derived from the hierarchical system of hens). Variations begin. A first concern is whether there’s actually a hierarchy, in the sense of gradations of rank. Instead, in some species (e.g., South American marmoset monkeys) there’s the alpha and there’s everyone else, with fairly equal relations. In species with gradations, there’s the issue of what a “rank” actually means. If your rank is number six in a hierarchy, in your mind are numbers one through five interchangeable guys you’d better kowtow to, while seven through infinity are undifferentiated peons? If so, it would be irrelevant to you if numbers two and three, or numbers nine and ten, were having tensions; rank gradations would be in the eyes of the primatologist, not the primate. In reality, such primates think about gradations of rank. For example, a baboon typically interacts differently with, say, the guy one step above him in rank than the one five steps above. Furthermore, primates note gradations that don’t directly concern them. Recall from chapter 10 how researchers recorded vocalizations of individuals in a troop, splicing them to invent social scenarios. Play a recording of number ten giving a dominance call and number one responding with a subordination call, and everyone pays attention: whoa, Bill Gates just panhandled a homeless guy. This can be abstracted further, as shown with ravens, which are outrageously smart birds. As with baboons, vocalizations implying dominance reversals command more attention than does the status quo. Remarkably, this even occurs for reversals between birds in a neighboring flock. Ravens discern dominance relations just by listening and are interested in hierarchical gossip about a different group. Next is the issue of variation within and among species as to what life is like having a particular rank. Does being high ranking merely mean that everyone keeps tabs on your mood or, at the other extreme, that no one else is getting enough calories to ovulate, lactate, or survive? How often do subordinates challenge dominant individuals? How readily do dominant individuals vent their frustrations on subordinates? How much do such subordinates have coping outlets (e.g., someone to groom with)? Then there is the issue of how high rank is attained. In many cases (e.g., female baboons, as noted) rank is inherited, a system with kin selection written all over it. In contrast, in other species/sexes (male baboons, for example) ranks shift over time, changing as a function of fights, showdowns, and Shakespearean melodrama, where rising in the hierarchy is about brawn, sharp canines, and winning the right fight.* Hurrah for clawing your way to the top, for sweaty, zero-sum, muscular capitalism. But what about the more interesting issue of how high rank, once attained, is maintained? As we’ll see, this has less to do with muscle than with social skills. This ushers in a key point—social competence is challenging, and this is reflected in the brain. The British anthropologist Robin Dunbar has shown that across various taxa (e.g., “birds,” “ungulates” or “primates”), the bigger the average size of the social group in the species, (a) the larger the brain, relative to total body size, and (b) the larger the neocortex, relative to total brain size. Dunbar’s influential “social brain hypothesis” posits that increases in social complexity and the evolutionary expansion of the neocortex have been linked. This link also occurs within species. Among some primates, group size can vary tenfold (depending on the richness of the ecosystem). This was modeled in a fascinating neuroimaging study, in which captive macaque monkeys were housed in different-sized groups; the bigger the group, the more thickening of the prefrontal cortex and the superior temporal gyrus, a cortical region involved in Theory of Mind, and the tighter the activity coupling between the two.3 Thus primate social complexity and big brains go together. This is shown further by examining fission-fusion species, where the size of the social group regularly changes dramatically. Baboons, for example, start and end the day in a large, coherent troop, whereas midday foraging occurs in small groups. As other examples, hyenas hunt in groups but scavenge individually, and wolves often do the opposite. Sociality is more complex in fission-fusion species. You must remember if someone’s rank differs when in a subgroup versus the entire group. Being away from someone all day makes it tempting to see if dominance relations have changed since breakfast. One study compared fission-fusion primates (chimps, bonobos, orangutans, spider monkeys) and non-fission-fusion (gorillas, capuchins, long-tailed macaques).4 Among these captive animals, fission-fusion species were better at frontocortical tasks and had larger neocortices relative to total brain size. Studies of corvids (crows, ravens, magpies, jackdaws) showed the same thing. Thus “rank” and “hierarchy” in other animals is anything but straightforward and varies considerably depending on the species, gender, and social group. H RANK AND HIERARCHY IN HUMANS uman hierarchies resemble those of other species in many ways. For example, there’s the distinction between stable and unstable hierarchies— centuries of czarist rule versus the first inning of the Russian Revolution. As we’ll see below, those situations evoke different patterns of brain activation. Group size also matters—primate species with bigger social groups have larger cortices relative to the rest of the brain (with humans topping off both measures).5 If you graph the size of the neocortex against the average size of the social group across primate species, you get “Dunbar’s number,” the predicted average group size in traditional human cultures. It’s 150 people, and there’s much evidence supporting that prediction. This also plays out in the Western world, where the larger the size of someone’s social network (often calculated by the number of e-mail/texting relationships), the larger the vmPFC, orbital PFC, and amygdala, and the better the person’s Theory of Mind–related skills.6 Do these brain regions expand when someone has a larger social network, or do larger sizes of these regions predispose people toward forming larger networks? Naturally, some of both. As with other species, human quality of life also varies with the consequences of rank inequalities—there’s a big difference between the powerful getting seated at a restaurant before you and the powerful getting to behead you if the fancy strikes them. Recall the study of thirty-seven countries showing that the more income inequality, the more preadolescent bullying in schools. In other words, countries with more brutal socioeconomic hierarchies produce children who enforce their own hierarchies more brutally.7 Amid these cross-species similarities, there are unique things about humans, including the following. Membership in Multiple Hierarchies We belong to multiple hierarchies and can have very different ranks in them. Naturally, this invites rationalization and system justification—deciding why hierarchies where we flounder are crap and the one where we reign really counts. Implicit in being part of multiple hierarchies is their potential overlap. Consider socioeconomic status, which encompasses both local and global hierarchies. I’m doing great socioeconomically—my car’s fancier than yours. I’m doing terribly—I’m not richer than Bill Gates. The Specialization of Some Ranking Systems A high-ranking chimp is generally good at related things. But humans can dwell in incredibly specialized hierarchies. Example: There’s a guy named Joey Chestnut who’s a god in one subculture—he’s the most successful competitive hot dog eater in history. However, whether Chestnut’s gift generalizes to other domains is unclear. Internal Standards This is the circumstance of having internal standards independent of the outside world. As an example, winning or losing at a team sport generally increases or decreases, respectively, testosterone levels in men. But things are subtler than that—testosterone more closely tracks winning through skill (rather than luck), and also more closely tracks individual (rather than team) performance.8 — Thus, as usual, we are just like other animals but totally different. We now consider the biology of individual ranks. THE VIEW FROM THE TOP, THE VIEW FROM THE BOTTOM Detecting Rank Much as with our ability to detect Thems, we’re intensely interested in and adept at spotting rank differences. For example, forty milliseconds is all we need to reliably distinguish between a dominant face (with direct gaze) and a subordinate one (with averted gaze and lowered eyebrows). Status is also signaled in the body, albeit to a less accurate extent—dominance with an exposed torso with arms wide open, subordination with arms sheltering a bent torso, intent on invisibility. Again, we recognize those cues at automatic speeds.9 Human infants also recognize status differences, as shown in a truly clever study. Show an infant a computer screen displaying a big square and little square; each has eyes and a mouth.10 The two squares are at opposite ends of the screen and repeatedly move to the other side, passing each other in the process. Then show a version where the two bump into each other—conflict. The squares bump repeatedly until one of them “gives in” by lying down, letting the other one pass. Toddlers look at the interaction longer when it’s the big square that gives in, rather than the little one. The first scenario is more interesting because it violates expectations—“Hey, I thought big squares dominated little squares.” Just like monkeys and corvids. But wait, this may just reflect folk physics, not attunement to hierarchy—big things knock over little things, not the other way around. This confound was eliminated. First, the adversarial squares were not touching when one gave in. Second, the subordinating one would fall in the opposite direction from that predicted by physics—rather than being knocked backward, it prostrates itself before the alpha square. Along with this expertise comes intense interest in hierarchy—as emphasized in chapter 9, gossip is mostly about the status of status: Are there any fallen mighty? Have the meek inherited anything lately? Regardless of which square wins, infants look longer at the conflict situation than when the squares peacefully glide past each other. This is logical self-interest. Knowing the hierarchical lay of the land helps you navigate it better. But there’s more to that than just self-interest. Those monkeys and corvids not only pay attention when there are rank reversals in their group; they do the same when eavesdropping on the neighbors. Same with us.11 What’s happening in our brains when we contemplate rank?12 Naturally, the prefrontal cortex weighs in. Frontal damage impairs skill at recognizing dominance relations (along with recognizing kinship, deception, or intimacy in faces). The vlPFC and dlPFC activate and become coupled when we figure out dominance relations or look at a dominant face, reflecting the combined affective and cognitive components to the process. These responses are most pronounced when considering someone of the opposite sex (which may reflect mating goals more than mere academic interest about hierarchy). Seeing a dominant face also activates the superior temporal gyrus (STG, with its role in Theory of Mind) and increases its coupling to the PFC—we’re more interested in what dominant individuals are thinking.13 Moreover, individual “social status” neurons occur in the monkeys. And as noted in chapter 2, contemplating an unstable hierarchy does all of the above, plus activates the amygdala, reflecting the unsettling effects of instability. Of course, though, none of this tells us what we are contemplating at these times. Your Brain and Your Own Status Your own rank does logical things to your brain. In macaque monkeys an increase in rank increases mesolimbic dopamine signaling. And back to that rhesus monkey study showing that being in a larger social group causes expansion and functional coupling of the STG and PFC. The study also showed that the higher the rank attained within each group, the greater the expansion and coupling. Consistent with that, a study of mice showed that higher-ranking animals had stronger excitatory inputs into the mouse equivalent of the (cognitive) dlPFC.14 I love these findings. As I said, in lots of social species, attaining high rank is about sharp teeth and good fighting skills. But maintaining the high rank is about social intelligence and impulse control: knowing which provocations to ignore and which coalitions to form, understanding other individuals’ actions. Does the monkey make history, or does history make the monkey? Once groups were formed, did individuals who became dominant respond with the biggest expansions of those brain regions? Or, prior to group formation, were the individuals destined to become dominant already endowed in those regions? Unfortunately, animals weren’t imaged before and after group formation in the study. However, subsequent work showed that the larger the size of the group, the larger the association between dominance and those brain changes, suggesting that attaining high rank drives the enlargement.* In contrast, the mouse study showed that when synaptic excitability was increased or decreased in the dlPFC, rank rose or declined, respectively, suggesting that enlargement drives attainment of high rank. The brain can shape behavior can shape the brain can shape . . .15 Your Body and Your Own Status What about biological differences outside the brain as a function of rank? For example, do high- and low-ranking males differ in their testosterone profiles and, if there are differences, are they causes, consequences, or mere correlates of the rank differences? Folk endocrinology has always held that high rank (in any species) and elevated testosterone levels go hand in hand, with the latter powering the former. But as covered at length in chapter 4, neither is the case in primates. As a reminder: In stable hierarchies high-ranking males typically don’t have the highest testosterone concentrations. Instead it’s usually low- ranking adolescent males, starting fights they can’t finish. When there is an association between high rank and high testosterone, it generally reflects the higher rates of sexual behavior among dominant individuals driving secretion. An exception to the above is during unstable times. For example, among a number of primate species, high-ranking males have the highest testosterone levels for the first months but not years after group formation. During unstable times, the high-testosterone/high-rank relationship is more a consequence of the high rates of fighting among the high-ranking cohort than of rank itself.16 Reiterating the “challenge hypothesis,” the elevation in testosterone levels caused by fighting is not so much about aggression as about challenge. If status is maintained aggressively, testosterone fosters aggression; if status were maintained by writing beautiful, delicate haikus, testosterone would foster that. Next we consider the relationship between rank and stress. Are different ranks associated with different levels of stress hormones, styles of coping, and incidences of stress-related disease? Is it more stressful to be dominant or subordinate? An extensive literature shows that a sense of control and predictability reduces stress. Yet monkey research conducted by Joseph Brady in 1958 produced a different view. Half the animals could press a bar to delay shocks (“executive” monkeys); the passive other half