Ostracism as a social and biological phenomenon: An introduction

Ostracism refers to the general process of rejection and exclusion, observed in human groups and in many other species. It occurs as “shunning” in small homogenous groups like the Amish or as rejection among children. Ostracism in various forms is also deeply embedded in our own legal tradition, and is used in the formal and informal legal procedures of other cultures, used to maintain order, to punish deviance, and to increase social cohesion. Hence, it is plausible to hypothesize that human ostracism may have physiological substrates or biological functions in addition to cultural, moral, and legal dimensions. Biological research shows that human emotions (anger, fear, reassurance, self-confidence) involve responses of the limbic system as well as ideas or thoughts in the cerebral cortex and that human behavior continually integrates biological and cultural factors. The legal system expresses and channels human behavior. For this reason laws should be more effective if their functions complement (rather than ignore) the function of the behavior being regulated. To look at law as it affects human behavior in the light of the life sciences does not imply the intention of finding a universally valid “natural law,” akin to theological or ideological doctrine. On the contrary, we find that humans can form radically different social systems due to the plasticity of their behavior. However, an interdisciplinary analysis of ostracism as a common area of behavior, combining biology, law, and the social sciences can produce insights that none of these fields alone can provide. Such an approach should increase our understanding of human nature and the functions of law.     

Ostracism,voice, and exit: The biology of social participation

A bewildering variety of social patterns can be described and analyzed as manifestations of ostracism and social rejection. Ostracism can be viewed as a coerced or involuntary rupture of social bonds, as distinguished from voluntary exit; both appear to be characteristic ways that animals use in relating to other members of the group. Based on Albert O. Hirschman's Exit, Voice and Loyalty, a general theoretical framework can be built on the realization that ostracism is far from a strange aberration—but that its excesses strike most moderns as uncivilized. This analysis presumes that active participation, flight, and bonding are general categories intrinsic to social behavior. It follows that, in different social contexts, the implications of ostracism vary greatly. Modern democratic systems, in which voluntary exit remains a possibility, resemble our hominid past more closely than authoritarian societies that place individuals in the unenviable position of being trapped in silence (with no legitimate right to exercise political voice, yet no possibility of escape). At the risk of Charges of valuative bias, the argument is made that democratic regimes may be—all things equal—closer to the center of our species-typical range of behavior than other kinds of centralized states or governmental systems.     

Human Sexual Differences in the Use of Social Ostracism as a Competitive Tactic

An aspect of social systems that is similar between chimpanzees and humans is that males form larger groups than females do. Both chimpanzee and human studies suggest that large groups are costlier for females than for males, so females attempt to reduce group size. Social ostracism of female group members occurs in both species and may serve as a mechanism for group size reduction. We formed groups of female and male children to examine directly whether human females would be more likely than males to employ social ostracism. We asked 7 female and 7 male groups of 10-yr-old children to compose and perform a play about a topic of interest to them. Female groups engaged in social ostracism more than male groups did. Further, within female groups, cortisol levels remained higher for female perpetrators of social ostracism than for their victims, suggesting that social ostracism is costly. In contrast, more frequent 1:1 conflictual behavior occurred in male than in female groups, but cortisol was unrelated to frequencies of 1:1 conflicts. Our results support the theory that human females find groups aversive and seek to reduce their size via social ostracism. Coalitions minimize the risk of retaliation but may induce costs.     

Pukhtunwali: Ostracism and honor among the Pathan Hill tribes

The Pathan Hill tribes provide an example of the functional role of ostracism in a face- to-face, kin-based society. “Pukhtunwali,” the Code of the Pathans, regulates the uses of ostracism, as a response to the conflict between an individual's desire for freedom and the necessity of tribal unity. The most striking use of ostracism among the Pathans is the rejection by the tribe or clan of one of its own members whose behavior might lead to feud. If a member of a group has committed an act likely to provoke a reprisal, which may be directed against any individual of that group, the guilty person may be expelled. By ostracizing the person, the group is both punishing him, and withdrawing its support. In Pathan society ostracism functions simultaneously to deter behavior that violates customary legal norms, to punish specific acts that are culturally defined as improper, and to unify the primary reference group on which individuals depend for protection and economic support.     

Ostracism and the law of defamation

This article compares the classical political institution of ostracism with the modern law of the United States concerning defamation. The classical institution of ostracism was a political tool of very limited scope. In modern society the term “ostracize” generally means to exclude a person from all or some of the benefits of a group. The law of defamation is a rather limited means of protecting an individual's reputation, consequently protecting individuals from being ostracized. The article concludes that United States law concerning defamation is generally inadequate as a means of protection from certain social consequences that resemble ostracism, such as job and educational discrimination. In addition, the article concludes that “the law seems to foster an unarticulated public policy that drifts in accordance with the preferences of individuals who have a great deal of personal or institutional power.”     

Capital punishment in tribal Montenegro: Implications for law,biology, and theory of social control

Clan execution among feuding tribal societies is proposed as a significant precursor to modern law. This form of ostracism is examined with respect to its social control functions and the indigenous assumptions about behavior, genes and demography that guide the behavior. It is suggested that there are very close parallels between modern legal systems and nonliterate ones based on “self-help”, when capital punishment is used by normal decision groups in the name of “national security”.     

AVPR1A Variation in Chimpanzees (Pan troglodytes): Population Differences and Association with Behavioral Style

Primates and other mammals show measurable, heritable variation in behavioral traits such as gregariousness, timidity, and aggression. Connections among behavior, environment, neuroanatomy, and genetics are complex, but small genetic differences can have large effects on behavioral phenotypes. One of the best examples of a single gene with large effects on natural variation in social behavior is AVPR1A, which codes for a receptor of the peptide hormone arginine vasopressin. Work on rodents shows a likely causal association between AVPR1A regulatory polymorphisms and social behavior. Chimpanzees also show variation in the AVPR1A regulatory region, with some individuals lacking a ca. 350-bp segment corresponding to a putative functional element. Thus, chimpanzees have a “short” allele (segment deletion) and a “long” allele (no deletion) at this locus. Here we compare AVPR1A variation in two chimpanzee populations, and we examine behavioral and hormonal data in relation to AVPR1A genotypes. We genotyped AVPR1A in a captive population of western chimpanzees (Pan troglodytes verus, New Iberia Research Center; N = 64) for which we had quantitative measures of personality (based on 15 behavioral style indices, calculated from 3 yr of observational data), dominance rank, and baseline testosterone levels. We also provide the first assessment of AVPR1A genotype frequencies in a wild eastern chimpanzee population (Pan troglodytes schweinfurthii, Ngogo community, Kibale National Park, Uganda; N = 26). Our results indicated that the AVPR1A long allele was associated with a “smart” social personality in captive western chimpanzees, independent of testosterone levels. Although the frequency of the long allele was relatively low in captive western chimpanzees (0.23), it was the major allele in wild eastern chimpanzees (0.62). Our finding that allele and genotype frequencies for the AVPR1A polymorphism differ among chimpanzee populations also highlights the need for comparative studies —across subspecies and research sites— in primate behavioral genetics.     

Myths of meritocracy: caste,karma and the new racism,a comparative study

The discourse of karma (behaviour), confounded with inherent psychic and material substance of the person/group (guna), was at the heart of India’s caste ideology. This systematic and intuitive, albeit convoluted and phantasmic doctrine was critical to bridge the discrepancy between a pantheistic religious imaginary and the reality of exclusion and abjection. Although “karma” evokes an exotic orient, this ideology is near identical with the ideas of “idleness” and “instant gratification” used to make sense of racial inequities in the contemporary United States. In both cases, the idea of behavioural and moral deficiency is used to justify evident abjection and discrimination, within the frame of an encompassing ideology of social equality. Thus, this use of the notions of “work” and “discipline”, extrapolated to the moral quality of the group or individual, is no passing argument of the “new racism”. It is a proven ploy of assigning blame on the victim.     

Female reproductive strategies, paternity and community structure in wild West African chimpanzees

Although the variability and complexity of chimpanzee behaviour frustrates generalization, it is widely believed that social evolution in this species occurs in the context of the recognizable social group or community. We used a combination of field observations and noninvasive genotyping to study the genetic structure of a habituated community of 55 wild chimpanzees, Pan troglodytes verus, in the Ta? Forest, C?te d'Ivoire. Pedigree relationships in that community show that female mate choice strategies are more variable than previously supposed and that the observed social groups are not the exclusive reproductive units. Genetic evidence based on nuclear microsatellite markers and behavioural obser-vations reveal that females in the Ta? forest actively seek mating partners outside their social unit; noncommunity males accounted for half the paternities over 5 years. This female mating strategy increases male gene flow between communities despite male philopatry, and negates the predicted higher relatedness among community males. Kin selection seems unlikely to explain the frequent cooperation and sharing observed among group males in this population. Similarly, inbreeding avoidance is probably not the sole cause of permanent adolescent female dispersal as a combination of extragroup mating and avoidance of incest with home group males would allow females to avoid inbreeding without the hazards associated with immigration into a new community. Extragroup mating as part of chimpanzee females' reproductive strategy may allow them to choose from a wider variety and number of males, without losing the resources and support provided by their male social group partners. Copyright 1999 The Association for the Study of Animal Behaviour.     

Comparison of the communicative vocalizations and behaviors of group ranging in eastern gorillas,chimpanzees and pygmy chimpanzees

Field observations were carried out on chimpanzees, pygmy chimpanzees and eastern gorillas. Since the communicative behaviors which appear in group ranging are closely related to the grouping of the animals and to the social structure, the communicative behaviors of group ranging were compared in the above three species in order to elucidate the common and different characters of their three much diversified social structures. The following conclusions were drawn: (1) the common ancestor ofGorilla andPan had the territorial call “hoot” and behavior of display, and males were antagonistic between each other in the society; (2) the common ancestral species did not have any special long distance cohesive calling: the society was a small compact one, moving on the ground; and (3) the social structure of the pygmy chimpanzee is very different from the common ancestral social structure when compared with those of the gorilla and chimpanzee, in that the pygmy chimpanzee has lost the behaviors of strong antagonistic character between adult males.     

A within-group gang attack on a young adult male chimpanzee: Ostracism of an ill-mannered member?

During a long-term study of wild chimpanzees in Tanzania, an unusual gang attack on a young adult male by the alpha male and seven other members of the same unit group (community) was observed and videotaped. Before the gang attack, the victim had not pant-grunted to the alpha male or to other adult males except for the second-ranked male, but had often bullied adult females without apparent reason. The alpha male's violent behavior, therefore, might have been punishment of or revenge against the ill-mannered young chimpanzee. This is the first record of an adult male other than an ex-alpha male becoming the object of ostracism by wild chimpanzees, although the victimized male did manage to return to the group after more than three months, when an ex-alpha male succeeded in reestablishing his former position.     

Primate social behavior and ostracism

Ostracism, and its attendant processes, emigration and immigration, are now recognized as basic mechanisms intrinsic to the long-term adaptation of primate society. Ostracism, defined as socially determined exclusion from the resources and opportunities necessary to successful reproduction, is a basic mechanism by which individuals strive to maximize their own reproductive success at the expense of others. Among males this process most often involves exclusion from opportunities to fertilize females (zygote formation) whereas among females it leads to competition for the resources necessary to raise these zygotes to adulthood. Ostracism from intrasexual competition may be so intense that it leads to the migration of less successful individuals into social groups offering greater opportunity. The “passports” most often used in primate immigration are sexual affinity and kinship alliance. Migration carries high risk and is associated with increased mortality and morbidity. Nevertheless, ostracism, emigration, and immigration remain as the basic social processes by which the ratio of resources to individuals shifts and balances from one year to the next. Such adjustments are made through the process of individual “decisions” and “strategies” to optimize personal reproductive success, but their net effect is to constantly redistribute individuals in relation to resources vital to reproduction.     

Individual acquisition of “stick pounding” behavior by naïve chimpanzees

Many studies investigating culture in nonhuman animals tend to focus on the inferred need of social learning mechanisms that transmit the form of a behavior to explain the population differences observed in wild animal behavioral repertoires. This research focus often results in studies overlooking the possibility of individuals being able to develop behavioral forms without requiring social learning. The disregard of individual learning abilities is most clearly observed in the nonhuman great ape literature, where there is a persistent claim that chimpanzee behaviors, in particular, require various forms of social learning mechanisms. These special social learning abilities have been argued to explain the acquisition of the relatively large behavioral repertoires observed across chimpanzee populations. However, current evidence suggests that although low‐fidelity social learning plays a role in harmonizing and stabilizing the frequency of behaviors within chimpanzee populations, some (if not all) of the forms that chimpanzee behaviors take may develop independently of social learning. If so, they would be latent solutions—behavioral forms that can (re‐)emerge even in the absence of observational opportunities, via individual (re)innovations. Through a combination of individual and low‐fidelity social learning, the population‐wide patterns of behaviors observed in great ape species are then established and stably maintained. This is the Zone of Latent Solutions (ZLS) hypothesis. The current study experimentally tested the ZLS hypothesis for pestle pounding, a wild chimpanzee behavior. We tested the reinnovation of this behavior in semi‐wild chimpanzees at Chimfunshi Wildlife Orphanage in Zambia, Africa, (N = 90, tested in four social groups). Crucially, all subjects were naïve to stick pounding before testing. Three out of the four tested groups reinnovated stick pounding—clearly demonstrating that this behavioral form does not require social learning. These findings provide support for the ZLS hypothesis alongside further evidence for the individual learning abilities of chimpanzees.     

An ethological study on chimpanzees at the artificial feeding place in the Mahale mountains,Tanzania—with special reference to the booming situation

A provisioned chimpanzee group in the Mahale Mountains was observed. The characteristic feature of chimpanzee behavior is that many types of behavior occur at one time as a bout of interactions. This can be seen in the booming situation in the wild. Similar situations were observed at the artificial feeding place. The behavior of the initiators of the interactions differed according to age, sex and social status. The chimpanzees' behavior was studied as a system. The relationships between each behavior pattern were investigated by analysis of the sequential behaviors of the same individual, and that of chains of signal-response behaviors, as well as that of behaviors which appeared when a third individual joined the initial interaction. Appeasement behaviors were more flexible, while others were more stereotyped. Part of the appeasement behavior resembled begging behavior. Appeasement behavior is thought to have a rather new phylogenetic origin. It is suggested that the various chimpanzee behaviors have evolved as a harmonious system which can be observed in the booming situation. The origin of chimpanzee society based on the evolution of their behavior system is discussed. Analysis of triplet interactions indicated that the types of triplet interaction in chimpanzees are quite different from those of multiple male group species such as macaques and baboons.     

An ethological study of pygmy chimpanzees in Wamba,Zaïre: A comparison with chimpanzees

An ethological study was conducted on a provisioned pygmy chimpanzee group in Wamba, Zaïre and was compared with the author's previous study on common chimpanzees, in Mahale Mountains with special reference to the evolution of behavior systems. The relationships between behavior patterns were investigated by analyses of the intra- or inter-individual sequential behaviors. Analysis of behavior pathways showed that “bipedal” was not found (i.e., observed frequency lower than expected value) in the course of the charging display in pygmy chimps, though it was an important element of the charging display in common chimps. Additionally, “bipedal” was found to be an initating behavior pattern in sexual behavior or dominant-subordinate behavior in pygmy chimps. These differences were related to the decrease of the role of charging display and to the increase of the roles of sexual and dominant-subordinate behaviors in pygmy chimps. Sexual behavior, “female genito-genital rubbing,” “mutual present” and frequent mounting and presenting between males were suggested to have evolved together as a system. These characteristics of behaviors correspond to the fact that pygmy chimps form more stable and larger temporary groups than common chimps.     

Collective action in culturally similar and dissimilar groups: an experiment on parochialism,conditional cooperation,and their linkages

This study examines the effects of ingroup favoritism and outgroup hostility (“parochialism”), as well as of conditionally cooperative strategies, in explaining contributions to experimental public goods games. The experimental conditions vary group composition along two culturally inheritable traits (political party preference and religious affiliation) and one trivial, “minimal” trait (birth season). We contrast ingroup, outgroup, and random group conditions and investigate the relation between the own contribution to the public good and the expectations about other group members' behavior in each one of them. We find evidence for ingroup favoritism but no support for a separate tendency towards outgroup hostility. Further, conditional cooperation and ingroup bias are, to some extent, linked. Subjects had higher expectations of the contributions of ingroup members, and their own behavior was more strongly conditioned on other group members' expected behavior in the ingroup conditions. In ingroup contexts, subjects displayed a form of “strong reciprocity” by giving more than they expected others to at high expectation levels but less at low expectation levels. Once these interactions are taken into account, we do not find a direct effect of ingroup bias anymore. We discuss these results in the light of theories of cultural group selection and conclude that too much emphasis may have been laid on direct intergroup conflict. Our results suggest that differential cooperativeness, rather than parochialism, may characterize the behavior of individuals in cultural ingroups and outgroups.     

Heritabilities,social environment effects and genetic correlations of social behaviours in a cooperatively breeding vertebrate

Social animals interact frequently with conspecifics, and their behaviour is influenced by social context, environmental cues and the behaviours of interaction partners, allowing for adaptive, flexible adjustments to social encounters. This flexibility can be limited by part of the behavioural variation being genetically determined. Furthermore, behaviours can be genetically correlated, potentially constraining independent evolution. Understanding social behaviour thus requires carefully disentangling genetic, environmental, maternal and social sources of variations as well as the correlation structure between behaviours. Here, we assessed heritability, maternal, common environment and social effects of eight social behaviours in Neolamprologus pulcher, a cooperatively breeding cichlid. We bred wild‐caught fish in a paternal half‐sibling design and scored ability to defend a resource against conspecifics, to integrate into a group and the propensity to help defending the group territory (“helping behaviour”). We assessed genetic, social and phenotypic correlations within clusters of behaviours predicted to be functionally related, namely “competition,” “aggression,” “aggression‐sociability,” “integration” and “integration‐help.” Helping behaviour and two affiliative behaviours were heritable, whereas there was little evidence for a genetic basis in all other traits. Phenotypic social effects explained part of the variation in a sociable and a submissive behaviour, but there were no maternal or common environment effects. Genetic and phenotypic correlation within clusters was mostly positive. A group's social environment influenced covariances of social behaviours. Genetic correlations were similar in magnitude but usually exceeding the phenotypic ones, indicating that conclusions about the evolution of social behaviours in this species could be provisionally drawn from phenotypic data in cases where data for genetic analyses are unobtainable.     

Death among geladas (Theropithecus gelada): a broader perspective on mummified infants and primate thanatology

Despite intensive study in humans, responses to dying and death have been a neglected area of research in other social mammals, including nonhuman primates. Two recent reports [Anderson JR, Gillies A, Lock LC. 2010. Pan thanatology. Current Biology 20:R349–R351; Biro D, Humle T, Koops K, Souse C, Hayashi M, Matsuzawa T. 2010. Chimpanzee mothers at Bossou, Guinea carry the mummified remains of their dead infants. Current Biology 20:R351–R352] offered exciting new insights into behavior toward dying and dead conspecifics in our closest living relatives—chimpanzees. Here, we provide a comparative perspective on primate thanatology using observations from a more distant human relative—gelada monkeys (Theropithecus gelada)—and discuss how gelada reactions to dead and dying groupmates differ from those recently reported for chimpanzees. Over a 3.75‐year study period, we observed 14 female geladas at Guassa, Ethiopia carrying dead infants from 1 hr to ≥48 days after death. Dead infants were carried by their mothers, other females in their group, and even by females belonging to other groups. Like other primate populations in which extended (>10 days) infant carrying after death has been reported, geladas at Guassa experience an extreme climate for primates, creating conditions which may favor slower rates of decomposition of dead individuals. We also witnessed the events leading up to the deaths of two individuals and the responses by groupmates to these dying individuals. Our results suggest that while chimpanzee mothers are not unique among primates in carrying their dead infants for long periods, seemingly “compassionate” caretaking behavior toward dying groupmates may be unique to chimpanzees among nonhuman primates (though it remains unknown whether such “compassionate” behavior occurs outside captivity). Am. J. Primatol. 73:405–409, 2011. © 2010 Wiley‐Liss, Inc.     

The Child on the Threshold of Becoming a Pupil

The functions of a preschooler's imagination that are required for a child to become immersed in the new social situation of development that characterizes the beginning of the early school ages are analyzed. The new social situation of development consists, above all, of new forms of interaction for the child with adults and other children within new primary activity—education. Imagination is viewed as a condition for the development of interaction during the older preschool ages based on a number of important indicators—the degree of development of social-communication skills and communicative competence—that underlie the “social component” of school readiness.     

Exclusion and shunning as legal and social sanctions

It seems difficult to determine which behavioral propensities are part of human biology and which are the results of cultural influences. If specific behavior patterns occur (perhaps with some variations) in all or most cultures, one might assume that they are based on innate behavioral tendencies. Exclusion and shunning are part of behavior patterns that have occurred again and again in various cultures throughout all recorded history as a response to deviant or abnormal behavior. This article examines the particular origins of the practice of “Ostrakismos” in ancient Athens, and its relationship to exile or exclusion from the legal community in various human cultures. With primitive peoples, and as evidenced in the laws of ancient Rome and medieval European kingdoms, outlawry was long a formalized sanction; also both Catholic and Lutheran religious laws provided explicitly for excommunication. In contrast, modern legal communities are less likely to exercise such formal expulsion of a member except under relatively extreme circumstances. The various data examined here may contribute to a comparative analysis of the behavior pattern “Exclusion and Shunning.”