The Impact of Hispanic and White Group Cues on Attitudes Towards the Violation of Generic Norms

While much work in political science has examined the impact of racial cues on individual perceptions, we know little about how individuals evaluate members of minority outgroups on issues that are not linked to stereotypes. We measure the impacts of Hispanic and White cues on individual assessments related to a stereotype-independent norm violation: alcoholism. We test three competing theories – cognition, intergroup emotions, and social identity – using a population-based vignette experiment included in the General Social Survey. Our results contradict much of the literature, but keep with social identity theory''s predictions. Hispanic alcoholics, when Hispanics constitute the outgroup, are assessed less negatively than White alcoholics in the ingroup, the latter experiencing what is called the black sheep effect. The black sheep effect occurs when ingroup members are more punitive towards members of the ingroup than the outgroup. However, the black sheep effect does not extend to measures that are more consistent with outgroup stereotypes, such as violence or money mismanagement; Hispanic alcoholics are evaluated more negatively than Whites on these measures. The implication is that the effect of racial cues depends strongly on issue linkages to group stereotypes.     

Indirect reciprocity and tradeoff paradigms in the wake of violent intergroup conflict

Intergroup interaction can be hindered by legacies of conflict and group biases. Many studies have looked at intergroup attitudes and pro-sociality in the wake of intergroup conflict, but few have explicitly studied how the group affiliation of another person affects the willingness to interact economically, especially when the interactions concern contested issues. In this study, I investigate the effect of group affiliation on the willingness to engage in economic interactions with others among individuals exposed to violent intergroup conflict, using a sample of refugees from the conflicts in Syria and Iraq. Based on the theory of indirect reciprocity, it is predicted that the tradeoff paradigms, that is, the willingness to engage in economic transactions with another individual, will depend on previous actions of other members of that individual's group. Participants tended to adopt a communal sharing tradeoff paradigm with ingroup members, and they tended to adopt a market pricing paradigm with outgroup members. However, this was the case only for those who reported that outgroup members had taken actions to harm them or their family in the conflict. For those who reported being harmed by members of the ingroup, a market pricing paradigm was employed also with ingroup members. The results suggest that group biases and indirect reciprocity after violent conflict do not necessarily arise from group identities alone, but as a function of past interactions with outgroup members.     

Pathogen threat and intergroup prejudice using the minimal group paradigm: Evidence from a registered report

Infection by parasites, bacteria, and other microorganisms has been a powerful selection pressure faced by humans and other species. Consequently, avoiding pathogens has played an important role in human evolution and continues to play a role in contemporary social psychological processes. The current research tested the hypothesis that pathogen avoidance promotes intergroup prejudice. Whereas previous tests relied on existing cultural groups, which can conflate outgroup status with pre-existing group stereotypes about disease or geographic variability in pathogen prevalence, the current experiments assessed intergroup bias using a minimal group paradigm. Based on preliminary evidence (Study 1, N = 207, undergraduate students) that experimentally priming pathogen avoidance motivation promoted negativity toward a minimal outgroup, we conducted a Registered Report (Study 2, N = 1339 online participants) to replicate and extend those findings. Our primary hypothesis was that an experimental manipulation of pathogen threat (relative to two control conditions) would produce greater intergroup prejudice (negativity toward the nominal outgroup relative to the nominal ingroup). This hypothesis was not supported in the larger, registered second study. Exploratory analyses provided some evidence for interactions between experimental priming of pathogen threat and individual differences in pathogen disgust, but the interactive pattern differed across the two experiments. Findings call into question the hypothesis that, in the absence of cultural stereotypes, situationally activated pathogen avoidance promotes intergroup prejudice.     

Does Competition Really Bring Out the Worst? Testosterone,Social Distance and Inter-Male Competition Shape Parochial Altruism in Human Males

Parochial altruism, defined as increased ingroup favoritism and heightened outgroup hostility, is a widespread feature of human societies that affects altruistic cooperation and punishment behavior, particularly in intergroup conflicts. Humans tend to protect fellow group members and fight against outsiders, even at substantial costs for themselves. Testosterone modulates responses to competition and social threat, but its exact role in the context of parochial altruism remains controversial. Here, we investigated how testosterone influences altruistic punishment tendencies in the presence of an intergroup competition. Fifty male soccer fans played an ultimatum game (UG), in which they faced anonymous proposers that could either be a fan of the same soccer team (ingroup) or were fans of other teams (outgroups) that differed in the degree of social distance and enmity to the ingroup. The UG was played in two contexts with varying degrees of intergroup rivalry. Our data show that unfair offers were rejected more frequently than fair proposals and the frequency of altruistic punishment increased with increasing social distance to the outgroups. Adding an intergroup competition led to a further escalation of outgroup hostility and reduced punishment of unfair ingroup members. High testosterone levels were associated with a relatively increased ingroup favoritism and also a change towards enhanced outgroup hostility in the intergroup competition. High testosterone concentrations further predicted increased proposer generosity in interactions with the ingroup. Altogether, a significant relation between testosterone and parochial altruism could be demonstrated, but only in the presence of an intergroup competition. In human males, testosterone may promote group coherence in the face of external threat, even against the urge to selfishly maximize personal reward. In that way, our observation refutes the view that testosterone generally promotes antisocial behaviors and aggressive responses, but underlines its rather specific role in the fine-tuning of male social cognition.     

Evolution and the psychology of intergroup conflict: the male warrior hypothesis

The social science literature contains numerous examples of human tribalism and parochialism-the tendency to categorize individuals on the basis of their group membership, and treat ingroup members benevolently and outgroup members malevolently. We hypothesize that this tribal inclination is an adaptive response to the threat of coalitional aggression and intergroup conflict perpetrated by 'warrior males' in both ancestral and modern human environments. Here, we describe how male coalitional aggression could have affected the social psychologies of men and women differently and present preliminary evidence from experimental social psychological studies testing various predictions from the 'male warrior' hypothesis. Finally, we discuss the theoretical implications of our research for studying intergroup relations both in humans and non-humans and discuss some practical implications.     

Group chorusing as an intragroup signal in the greater ani,a communally breeding bird

Group living often requires maintaining dynamic and varied relationships with fellow group members, while simultaneously monitoring and interacting with external competitors. Group members in many social species vocalize together to produce duets or choruses—coordinated, often conspicuous vocal displays—that may play a role in these interactions. Compared with male–female duets, however, relatively little research exists on the function and adaptive significance of group choruses, which involve three or more individuals. Here we investigate chorusing behavior in the greater ani (Crotophaga major), a communally breeding cuckoo that nests in stable social groups of four to eight unrelated individuals. Groups may remain together for several years on the same nesting territory, and groups occasionally destroy each other's clutches in conflicts over high-quality territories. We asked whether the raucous, highly stereotyped choruses performed by ani groups are primarily used for intra- or intergroup communication, and whether they contain information about the identity of the social group and the number of birds vocalizing. Behavioral observations and acoustic recordings from three breeding seasons revealed that choruses typically occurred during social interactions within the group (78% of choruses) or in response to a predator or extra-group individual (17%) and only rarely in intergroup interactions (4%). Consistent with this finding, choruses did not reliably reflect the number of birds vocalizing, and we found only limited evidence for group-specific acoustic signatures (driven by a single group whose choruses were highly distinct). These results suggest that group choruses play an important role in intra-group signaling, potentially in contexts such as group formation, reinforcement of social bonds within the group, and/or collective decision-making, and they motivate new research questions about the role of collective signaling in social evolution.     

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.     

Intergroup bias in third-party punishment stems from both ingroup favoritism and outgroup discrimination

Social norms pervade almost every aspect of social interaction. If they are violated, not only legal institutions, but other members of society as well, punish, i.e., inflict costs on the wrongdoer. Sanctioning occurs even when the punishers themselves were not harmed directly and even when it is costly for them. There is evidence for intergroup bias in this third-party punishment: third-parties, who share group membership with victims, punish outgroup perpetrators more harshly than ingroup perpetrators. However, it is unknown whether a discriminatory treatment of outgroup perpetrators (outgroup discrimination) or a preferential treatment of ingroup perpetrators (ingroup favoritism) drives this bias. To answer this question, the punishment of outgroup and ingroup perpetrators must be compared to a baseline, i.e., unaffiliated perpetrators. By applying a costly punishment game, we found stronger punishment of outgroup versus unaffiliated perpetrators and weaker punishment of ingroup versus unaffiliated perpetrators. This demonstrates that both ingroup favoritism and outgroup discrimination drive intergroup bias in third-party punishment of perpetrators that belong to distinct social groups.     

The cultural contagion of conflict

Anecdotal evidence abounds that conflicts between two individuals can spread across networks to involve a multitude of others. We advance a cultural transmission model of intergroup conflict where conflict contagion is seen as a consequence of universal human traits (ingroup preference, outgroup hostility; i.e. parochial altruism) which give their strongest expression in particular cultural contexts. Qualitative interviews conducted in the Middle East, USA and Canada suggest that parochial altruism processes vary across cultural groups and are most likely to occur in collectivistic cultural contexts that have high ingroup loyalty. Implications for future neuroscience and computational research needed to understand the emergence of intergroup conflict are discussed.     

Association between burst-pulse sounds and aggressive behavior in captive Atlantic bottlenosed dolphins (Tursiops truncatus)

A specific display observed during agonistic behavior among captive Atlantic bottlenosed dolphins (Tursiops truncatus) was examined. The primary component of the display was an open-mouthed posture accompanied by violent vertical head motions and the emission of pulse-type vocalizations. Jaw-clap behavior produced during the display was quantified for use as an index of aggressive motivation. By aurally monitoring the animals' vocalizations it was found that the level of aggressive response between the participants of the interactions increased with the production and subsequent duration of burst-pulse sounds. The possibility of burstpulse sounds resulting in auditory or tactile discomfort when directed toward conspecifics is discussed.     

A Puzzle Unsolved: Failure to Observe Different Effects of God and Religion Primes on Intergroup Attitudes

Religious priming has been found to have both positive and negative consequences, and recent research suggests that the activation of God-related and community-related religious cognitions may cause outgroup prosociality and outgroup derogation respectively. The present research sought to examine whether reminders of God and religion have different effects on attitudes towards ingroup and outgroup members. Over two studies, little evidence was found for different effects of these two types of religious primes. In study 1, individuals primed with the words “religion”, “God” and a neutral control word evaluated both ingroup and outgroup members similarly, although a marginal tendency towards more negative evaluations of outgroup members by females exposed to religion primes was observed. In study 2, no significant differences in attitudes towards an outgroup member were observed between the God, religion, and neutral priming conditions. Furthermore, the gender effect observed in study 1 did not replicate in this second study. Possible explanations for these null effects are discussed.     

Conflict, sticks and carrots: war increases prosocial punishments and rewards

Unlike most species, humans cooperate extensively with group members who are not closely related to them, a pattern sustained in part by punishing non-cooperators and rewarding cooperators. Because internally cooperative groups prevail over less cooperative rival groups, it is thought that violent intergroup conflict played a key role in the evolution of human cooperation. Consequently, it is plausible that propensities to punish and reward will be elevated during intergroup conflict. Using experiments conducted before, during and after the 2006 Israel-Hezbollah war, we show that, during wartime, people are more willing to pay costs to punish non-cooperative group members and reward cooperative group members. Rather than simply increasing within-group solidarity, violent intergroup conflict thus elicits behaviours that, writ large, enhance cooperation within the group, thereby making victory more likely.     

Intergroup Contact Effects via Ingroup Distancing among Majority and Minority Groups: Moderation by Social Dominance Orientation

Five studies tested whether intergroup contact reduces negative outgroup attitudes through a process of ingroup distancing. Based on the deprovincialization hypothesis and Social Dominance Theory, we hypothesized that the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup identification is moderated by individuals’ Social Dominance Orientation (SDO), and occurs only for members of high status majority groups. We tested these predictions in three different intergroup contexts, involving conflictual relations between social groups in Germany (Study 1; N = 150; longitudinal Study 2: N = 753), Northern Ireland (Study 3: N = 160; Study 4: N = 1,948), and England (Study 5; N = 594). Cross-group friendship was associated with reduced ingroup identification and the link between reduced ingroup identification and improved outgroup attitudes was moderated by SDO (the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup only occurred for individuals scoring high, but not low, in SDO). Although there was a consistent moderating effect of SDO in high-status majority groups (Studies 1–5), but not low-status minority groups (Studies 3, 4, and 5), the interaction by SDO was not reliably stronger in high- than low-status groups. Findings are discussed in terms of better understanding deprovincialization effects of contact.     

On the transmission of HIV with self-protective behavior and preferred mixing

An epidemic model of HIV transmission with self-protective behavior and preferred mixing is presented. Individuals in the model are assumed to choose their levels of risk behavior by comparing the costs and benefits of self-protective actions. Unlike in models which treat individual risk behavior as exogenously given and fixed, the condition under which an endemic steady state equilibrium exists does not depend on the extent of assortative mixing in the population. Specifically, a unique endemic equilibrium exists when the basic reproductive number of the disease, which is given in the model by the expected number of secondary infections caused by an infected individual in the absence of any self-protection, is strictly greater than one. Otherwise, the disease-free equilibrium is the only steady state equilibrium. With respect to changes in contact patterns, it is shown that, if the degree of preferred mixing is increased, the disease prevalence can decrease in the high-risk subpopulation consisting of individuals who are more likely to engage in unsafe practices. The situation is reversed for the low-risk subpopulation, which is composed of individuals who are less willing to engage in risky practices, so that increasing the likelihood of mixing with members of one's own group may increase the prevalence level within the low-risk subpopulation.     

The dynamics of social cohesion in response to simulated intergroup conflict in banded mongooses

Intergroup conflict is widespread in nature and is proposed to have strong impacts on the evolution of social behavior. The conflict–cohesion hypothesis predicts that exposure to intergroup conflict should lead to increased social cohesion to improve group success or resilience in future conflicts. There is evidence to support this prediction from studies of affiliative responses to outgroup threats in some animal societies. However, most of these studies have focused on behavioral changes over short time periods (minutes and hours after exposure to an outgroup), and hence very little is known about the dynamics and durability of responses to intergroup conflict over the longer term. We investigated this question by simulating intergroup encounters in wild banded mongooses (Mungos mungo) and measuring social behavior before, during, and after these encounters over a 5‐day period. We also ran control trials with non‐threatening stimuli. Banded mongooses reacted immediately to intrusion stimuli by vocalizing, grouping together, and advancing on the stimulus. In the first 5 min after simulated intrusions, we saw an elevation in grooming levels, but in the hour after exposure grooming rates declined sharply, contrary to our expectation. In the two subsequent days, grooming rates remained at this depressed rate. In control trials, the initial increase in grooming was not seen, but grooming declined compared to the longer‐term time periods. Grooming changed across time, but not in the same pattern as during intrusions, suggesting that intrusions had an impact above and beyond that of the experimental setup. The dynamics of grooming responses were short lived and more complex than we initially expected. We suggest this unexpected result may be linked to the frequency of aggressive intergroup encounters in this system. As control and experimental trials were run at different times of year, future work would be needed to confirm that these relative patterns are replicable. Our results indicate short‐lived impacts of outgroup threat on measures of social cohesion in this species, but cannot confirm longer‐term changes.     

The co-evolution of individual behaviors and social institutions

We present agent-based simulations of a model of a deme-structured population in which group differences in social institutions are culturally transmitted and individual behaviors are genetically transmitted. We use a standard extended fitness accounting framework to identify the parameter space for which this co-evolutionary process generates high levels of group-beneficial behaviors. We show that intergroup conflicts may explain the evolutionary success of both: (a) altruistic forms of human sociality towards unrelated members of one's group; and (b) group-level institutional structures such as food sharing which have emerged and diffused repeatedly in a wide variety of ecologies during the course of human history. Group-beneficial behaviors may evolve if (a) they inflict sufficient fitness costs on outgroup individuals and (b) group-level institutions limit the individual fitness costs of these behaviors and thereby attenuate within-group selection against these behaviors. Thus, the evolutionary success of individually costly but group-beneficial behaviors in the relevant environments during the first 90,000 years of anatomically modern human existence may have been a consequence of distinctive human capacities in social institution building.     

Social Hostility in Soccer and Beyond

Social hostility is seldom expressed overtly. More often than not, individuals try to get their hostile message across without risking violent altercations. However, subtle and relatively covert hostility is not easy to research. We suggest a novel way with the SoMi paradigm, a social decision making task that offers participants the opportunity to be socially mindful or socially hostile by leaving or limiting choice to others. Sampling a general population we find that, relative to friends and strangers, foes are indeed met with greater social hostility (Study 1). Focusing on the highly competitive environment of youth soccer, we find that rival team members elicit social hostility, whereas teammates elicit social mindfulness (Study 2). We conclude that social mindfulness and social hostility play a subtle role in the dynamics of interpersonal and/or intergroup relationships, in which leaving or limiting choice is one of the subtle ways to express benevolent versus hostile intentions; the SoMi paradigm may thus be helpful in identifying which way the ball rolls.     

Intergroup affiliative interactions and intergroup transfer of young male Japanese macaques (Macaca fuscata)

The social interactions between young male Japanese macaques (Macaca fuscata) and members of two adjacent groups were studied. Young males usually associated with members of a single group. Although some young males occasionally interacted with members of the neighboring group, the frequency of their intergroup affiliative interactions was much lower than that of their intragroup interactions. The intergroup affiliative interactions were less symmetrical than the intragroup interactions. Three- or four-year-old males who remained in their natal group interacted with males of the neighboring group, whereas males over 5 years old did not. Young males revealed a dramatic change in their association partners from males in one group to those in another during the course of their intergroup transfer. Males who remained in their natal group did not attempt to interact with females of the neighboring group. In contrast, males who had transferred to a non-natal group interacted with females in their natal group. It is suggested that intergroup affiliative interactions and intergroup transfer of young male macaques are influenced by close associations between males. The immediate motivation for transfer of young natal macaques may be some attraction to males outside their group rather than sexual attraction to unfamiliar females.     

兴隆山自然保护区麝场圈养马麝刻板行为的比较

于2001年3月—2002年1月,采用焦点取样法对甘肃兴隆山自然保护区麝场圈养马麝的刻板行为进行了研究。结果表明:该麝场的圈养马麝有刻板行为的发育,雌麝的刻板行为持续时间少于雄麝,但二者间的差异不显著。野捕马麝幼年期的人工哺乳经历使其刻板行为表达强度相对小于麝场圈养下繁殖马麝。年龄对雌雄麝的刻板行为表达强度的效应相似,亚成体马麝的刻板行为表达较多,成体马麝体的刻板行为表达相对较少,老年马麝刻板行为持续时间最长,2.5和4.5岁是圈养马麝刻板行为发育的关键时期。此外,能顺利繁殖的个体,其刻板行为表达的持续时间少于繁殖失败的个体。