Mark Schaller

Does Social Exclusion Motivate Interpersonal Reconnection? Resolving the "Porcupine Problem"

Evidence from 6 experiments supports the social reconnection hypothesis, which posits that the experience of social exclusion increases the motivation to forge social bonds with new sources of potential affiliation. Threat of social exclusion led participants to express greater interest in making new friends, to increase their desire to work with others, to form more positive impressions of novel social targets, and to assign greater rewards to new interaction partners. Findings also suggest potential boundary conditions to the social reconnection hypothesis. Excluded individuals did not seem to seek reconnection with the specific perpetrators of exclusion or with novel partners with whom no face-to-face interaction was anticipated. Furthermore, fear of negative evaluation moderated responses to exclusion such that participants low in fear of negative evaluation responded to new interaction partners in an affiliative fashion, whereas participants high in fear of negative evaluation did not.

Renovating the Pyramid of Needs: Contemporary Extensions Built Upon Ancient Foundations

Maslow’s pyramid of human needs, proposed in 1943, has been one of the most cognitively contagious ideas in the behavioral sciences. Anticipating later evolutionary views of human motivation and cognition, Maslow viewed human motives as based in innate and universal predispositions. We revisit the idea of a motivational hierarchy in light of theoretical developments at the interface of evolutionary biology, anthropology, and psychology. After considering motives at three different levels of analysis, we argue that the basic foundational structure of the pyramid is worth preserving, but that it should be buttressed with a few architectural extensions. By adding a contemporary design feature, connections between fundamental motives and immediate situational threats and opportunities should be highlighted. By incorporating a classical element, these connections can be strengthened by anchoring the hierarchy of human motives more firmly in the bedrock of modern evolutionary theory. We propose a renovated hierarchy of fundamental motives that serves as both an integrative framework and a generative foundation for future empirical research.

Pathogen prevalence predicts human cross-cultural variability in individualism/collectivism

Pathogenic diseases impose selection pressures on the social behaviour of host populations. In humans (Homo sapiens), many psychological phenomena appear to serve an antipathogen defence function. One broad implication is the existence of cross-cultural differences in human cognition and behaviour contingent upon the relative presence of pathogens in the local ecology. We focus specifically on one fundamental cultural variable: differences in individualistic versus collectivist values. We suggest that specific behavioural manifestations of collectivism (e.g. ethnocentrism, conformity) can inhibit the transmission of pathogens; and so we hypothesize that collectivism (compared with individualism) will more often characterize cultures in regions that have historically had higher prevalence of pathogens. Drawing on epidemiological data and the findings of worldwide cross-national surveys of individualism/collectivism, our results support this hypothesis: the regional prevalence of pathogens has a strong positive correlation with cultural indicators of collectivism and a strong negative correlation with individualism. The correlations remain significant even when controlling for potential confounding variables. These results help to explain the origin of a paradigmatic cross-cultural difference, and reveal previously undocumented consequences of pathogenic diseases on the variable nature of human societies.

Pathogens, Personality, and Culture: Disease Prevalence Predicts Worldwide Variability in Sociosexuality, Extraversion, and Openness to Experience

Previous research has documented cross-cultural differences in personality traits, but the origins of those differences remain unknown. The authors investigate the possibility that these cultural differences can be traced, in part, to regional differences in the prevalence in infectious diseases. Three specific hypotheses are deduced, predicting negative relationships between disease prevalence and (a) unrestricted sociosexuality, (b) extraversion, and (c) openness to experience. These hypotheses were tested empirically with methods that employed epidemiological atlases in conjunction with personality data collected from individuals in dozens of countries worldwide. Results were consistent with all three hypotheses: In regions that have historically suffered from high levels of infectious diseases, people report lower mean levels of sociosexuality, extraversion, and openness. Alternative explanations are addressed, and possible underlying mechanisms are discussed.

Evolved Disease-Avoidance Mechanisms and Contemporary Xenophobic Attitudes

From evolutionary psychological reasoning, we derived the hypothesis that chronic and contextually aroused feelings of vulnerability to disease motivate negative reactions to foreign peoples. The hypothesis was tested and supported across four correlational studies: chronic disease worries predicted implicit cognitions associating foreign outgroups with danger, and also predicted less positive attitudes toward foreign (but not familiar) immigrant groups. The hypothesis also received support in two experiments in which the salience of contagious disease was manipulated: participants under high disease-salience conditions expressed less positive attitudes toward foreign (but not familiar) immigrants and were more likely to endorse policies that would favor the immigration of familiar rather than foreign peoples. These results reveal a previously under-explored influence on xenophobic attitudes, and suggest interesting linkages between evolved disease-avoidance mechanisms and contemporary social cognition.

EVOLVED DISEASE-AVOIDANCE PROCESSES AND CONTEMPORARY ANTI-SOCIAL BEHAVIOR: PREJUDICIAL ATTITUDES AND AVOIDANCE OF PEOPLE WITH PHYSICAL DISABILITIES

Drawing on evolutionary psychological logic, we describe a model that links evolved mechanisms of disease-avoidance to contemporary prejudices against individuals with physical disabilities. Because contagious diseases were often accompanied by anomalous physical features, humans plausibly evolved psychological mechanisms that respond heuristically to the perception of these features, triggering specific emotions (disgust, anxiety), cognitions (negative attitudes), and behaviors (avoidance). This disease-avoidance system is over-inclusive: Anomalous features that are not due to disease (e.g., limb amputation due to accident) may also activate it, contributing to prejudicial attitudes and behaviors directed toward people with disabilities. This model implies novel hypotheses about contemporary variables that may amplify or reduce disability-based prejudice. We discuss past research within this context. We also present new evidence linking chronic and temporary concerns about disease to implicit negative attitudes toward and behavioral avoidance of disabled others. Discussion focuses on the conceptual and practical implications of this evolutionary approach.

The Behavioral Immune System (and Why It Matters)

Like many other animals, human beings engage in behavioral defenses against infectious pathogens. The behavioral immune system consists of a suite of psychological mechanisms that (a) detect cues connoting the presence of infectious pathogens in the immediate environment, (b) trigger disease-relevant emotional and cognitive responses, and thus (c) facilitate behavioral avoidance of pathogen infection. However, the system responds to an overly general set of superficial cues, which can result in aversive responses to things (including people) that pose no actual threat of pathogen infection. In addition, the system is flexible, such that more strongly aversive responses occur under conditions in which perceivers are (or merely perceive themselves to be) more vulnerable to pathogen infection. Recent research reveals many provocative implications—for the experience of disgust, for extraversion and social interaction, for xenophobia and other prejudices, and for the origins of cultural differences.

Human Threat Management Systems: Self-Protection and Disease Avoidance

Humans likely evolved precautionary systems designed to minimize the threats to reproductive fitness posed by highly interdependent ultrasociality. A review of research on the self-protection and disease avoidance systems reveals that each system is functionally distinct and domain-specific: each is attuned to different cues; engages different emotions, inferences, and behavioral inclinations; and is rooted in somewhat different neurobiological substrates. These systems share important features, however. Each system is functionally coherent, in that perceptual, affective, cognitive, and behavioral processes work in concert to reduce fitness costs of potential threats. Each system is biased in a risk-averse manner, erring toward precautionary responses even when available cues only heuristically imply threat. And each system is functionally flexible, being highly sensitive to specific ecological and dispositional cues that signal greater vulnerability to the relevant threat. These features characterize a general template useful for understanding not only the self-protection and disease avoidance systems, but also a broader set of evolved, domain-specific precautionary systems.

Fear of the Dark: Interactive Effects of Beliefs about Danger and Ambient Darkness on Ethnic Stereotypes

Two studies examined effects of ambient darkness and chronic beliefs about danger on activation of stereotypes about Blacks. Chronic beliefs were measured by a Belief in a Dangerous World (BDW) questionnaire. In Study, 1, participants in either a dimly lit or dark room saw photos of Black men and rated the extent to which specific traits described the cultural stereotype of Blacks. In Study 2, participants in either a well-lit or dark room completed reaction-time tasks assessing implicit associations between Blacks and evaluative attributes. Separate measures assessed stereotypes connoting danger versus those that are merely derogatory. Results revealed BDW × Darkness interactions on activation of danger-relevant stereotypes: BDW positively predicted activation in dark but not in light conditions. It appears that chronic beliefs about danger can facilitate activation of functionally relevant stereotypes, but this effect occurs primarily under circumstances (such as darkness) that heuristically suggest vulnerability to harm. Conceptual implications are discussed.

The Prejudiced Personality Revisited: Personal Need for Structure and Formation of Erroneous Group Stereotypes

Two studies explored the relation between personal need for structure (PNS) and a reasoning process through which stereotypes may form. Participants viewed information about the performance of group members on intelligence-related tasks and then indicated their inference strategies and impressions of the groups. Results indicated that high-PNS participants were more likely than low-PNS participants to form erroneous group stereotypes. Individual differences in attributional complexity and need for cognition also predicted stereotype formation under some conditions. The effects of PNS and other cognitive personality variables were weakened under conditions in which participants believed that they would have to justify their impressions publicly. Discussion focuses on processes underlying the relation between PNS and stereotype formation and on relations among personality, social context, and social inference