Explaining the evolution of gossip.

Gossip, the exchange of personal information about absent third parties, is ubiquitous in human societies. However, the evolution of gossip remains a puzzle. The current article proposes an evolutionary cycle of gossip and uses an agent-based evolutionary game-theoretic model to assess it. We argue that the evolution of gossip is the joint consequence of its reputation dissemination and selfishness deterrence functions. Specifically, the dissemination of information about individuals' reputations leads more individuals to condition their behavior on others' reputations. This induces individuals to behave more cooperatively toward gossipers in order to improve their reputations. As a result, gossiping has an evolutionary advantage that leads to its proliferation. The evolution of gossip further facilitates these two functions of gossip and sustains the evolutionary cycle.

Multilevel cultural evolution: From new theory to practical applications.

Evolutionary science has led to many practical applications of genetic evolution but few practical uses of cultural evolution. This is because the entire study of evolution was gene centric for most of the 20th century, relegating the study and application of human cultural change to other disciplines. The formal study of human cultural evolution began in the 1970s and has matured to the point of deriving practical applications. We provide an overview of these developments and examples for the topic areas of complex systems science and engineering, economics and business, mental health and well-being, and global change efforts.

Norm Dynamics: Interdisciplinary Perspectives on Social Norm Emergence, Persistence, and Change.

Social norms are the glue that holds society together, yet our knowledge of them remains heavily intellectually siloed. This article provides an interdisciplinary review of the emerging field of norm dynamics by integrating research across the social sciences through a cultural-evolutionary lens. After reviewing key distinctions in theory and method, we discuss research on norm psychology-the neural and cognitive underpinnings of social norm learning and acquisition. We then overview how norms emerge and spread through intergenerational transmission, social networks, and group-level ecological and historical factors. Next, we discuss multilevel factors that lead norms to persist, change, or erode over time. We also consider cultural mismatches that can arise when a changing environment leads once-beneficial norms to become maladaptive. Finally, we discuss potential future research directions and the implications of norm dynamics for theory and policy.

When danger strikes: A linguistic tool for tracking America's collective response to threats.

In today's vast digital landscape, people are constantly exposed to threatening language, which attracts attention and activates the human brain's fear circuitry. However, to date, we have lacked the tools needed to identify threatening language and track its impact on human groups. To fill this gap, we developed a threat dictionary, a computationally derived linguistic tool that indexes threat levels from mass communication channels. We demonstrate this measure's convergent validity with objective threats in American history, including violent conflicts, natural disasters, and pathogen outbreaks such as the COVID-19 pandemic. Moreover, the dictionary offers predictive insights on US society's shifting cultural norms, political attitudes, and macroeconomic activities. Using data from newspapers that span over 100 years, we found change in threats to be associated with tighter social norms and collectivistic values, stronger approval of sitting US presidents, greater ethnocentrism and conservatism, lower stock prices, and less innovation. The data also showed that threatening language is contagious. In all, the language of threats is a powerful tool that can inform researchers and policy makers on the public's daily exposure to threatening language and make visible interesting societal patterns across American history.

From virility to virtue: the psychology of apology in honor cultures.

In honor cultures, relatively minor disputes can escalate, making numerous forms of aggression widespread. We find evidence that honor cultures' focus on virility impedes a key conflict de-escalation strategy-apology-that can be successfully promoted through a shift in mindset. Across five studies using mixed methods (text analysis of congressional speeches, a cross-cultural comparison, surveys, and experiments), people from honor societies (e.g., Turkey and US honor states), people who endorse honor values, and people who imagine living in a society with strong honor norms are less willing to apologize for their transgressions (studies 1-4). This apology reluctance is driven by concerns about reputation in honor cultures. Notably, honor is achieved not only by upholding strength and reputation (virility) but also through moral integrity (virtue). The dual focus of honor suggests a potential mechanism for promoting apologies: shifting the focus of honor from reputation to moral integrity. Indeed, we find that such a shift led people in honor cultures to perceive apologizing more positively and apologize more (study 5). By identifying a barrier to apologizing in honor cultures and illustrating ways to overcome it, our research provides insights for deploying culturally intelligent conflict-management strategies in such contexts.

When guiding principles do not guide: The moderating effects of cultural tightness on value-behavior links.

OBJECTIVE: Ample research documented the effects of guiding principles in people's lives, as reflected in personal values, on a variety of behaviors. But do these principles universally guide behaviors across all cultural contexts? To address this question, we investigated the effect of cross-cultural differences in the strength of social norms (i.e., tightness-looseness) on value-behavior relationships. METHOD: Using the archival data from the World Value Survey for 24 nations (N = 38,924; 51.40% female; Mage  = 44.98, SD = 16.87), a multi-level analysis revealed that cultural tightness moderated the effects of individual differences in personal values on behaviors from different life-domains. RESULTS: As hypothesized, the relationships between self-transcendence values with civic involvement and pro-environmental behaviors, and between conservation values with religious behavior were significantly stronger in loose cultures that have weak norms and were almost nonexistent in tight cultures that have strong norms, even when controlling for individualism-collectivism or GDP. CONCLUSIONS: Thus, despite the common belief that people behave in line with their guiding principles, our findings suggest this might not be the case in cultural contexts that put a strong emphasis on norms.

Revenge: A Multilevel Review and Synthesis.

Why do people take revenge? This question can be difficult to answer. Vengeance seems interpersonally destructive and antithetical to many of the most basic human instincts. However, an emerging body of social scientific research has begun to illustrate a logic to revenge, demonstrating why revenge evolved in humans and when and how people take revenge. We review this evidence and suggest that future studies on revenge would benefit from a multilevel perspective in which individual acts of revenge exist within higher-level cultural systems, with the potential to instigate change in these systems over time. With this framework, we can better understand the interplay between revenge's psychological properties and its role in cultural evolution.

Ambivalent stereotypes link to peace, conflict, and inequality across 38 nations.

A cross-national study, 49 samples in 38 nations (n = 4,344), investigates whether national peace and conflict reflect ambivalent warmth and competence stereotypes: High-conflict societies (Pakistan) may need clearcut, unambivalent group images distinguishing friends from foes. Highly peaceful countries (Denmark) also may need less ambivalence because most groups occupy the shared national identity, with only a few outcasts. Finally, nations with intermediate conflict (United States) may need ambivalence to justify more complex intergroup-system stability. Using the Global Peace Index to measure conflict, a curvilinear (quadratic) relationship between ambivalence and conflict highlights how both extremely peaceful and extremely conflictual countries display lower stereotype ambivalence, whereas countries intermediate on peace-conflict present higher ambivalence. These data also replicated a linear inequality-ambivalence relationship.

Conflicting obligations in human social life.

Tomasello describes how the sense of moral obligation emerges from a shared perspective with collaborative partners and in-group members. Our commentary expands this framework to accommodate multiple social identities, where the normative standards associated with diverse group memberships can often conflict with one another. Reconciling these conflicting obligations is argued to be a central part of human morality.

How culture gets embrained: Cultural differences in event-related potentials of social norm violations.

Humans are unique among all species in their ability to develop and enforce social norms, but there is wide variation in the strength of social norms across human societies. Despite this fundamental aspect of human nature, there has been surprisingly little research on how social norm violations are detected at the neurobiological level. Building on the emerging field of cultural neuroscience, we combine noninvasive electroencephalography (EEG) with a new social norm violation paradigm to examine the neural mechanisms underlying the detection of norm violations and how they vary across cultures. EEG recordings from Chinese and US participants (n = 50) showed consistent negative deflection of event-related potential around 400 ms (N400) over the central and parietal regions that served as a culture-general neural marker of detecting norm violations. The N400 at the frontal and temporal regions, however, was only observed among Chinese but not US participants, illustrating culture-specific neural substrates of the detection of norm violations. Further, the frontal N400 predicted a variety of behavioral and attitudinal measurements related to the strength of social norms that have been found at the national and state levels, including higher culture superiority and self-control but lower creativity. There were no cultural differences in the N400 induced by semantic violation, suggesting a unique cultural influence on social norm violation detection. In all, these findings provided the first evidence, to our knowledge, for the neurobiological foundations of social norm violation detection and its variation across cultures.

The role of entitativity in perpetuating cycles of violence.

Whitehouse's theory on fusion can explain why suicide terrorists are willing to make the ultimate sacrifice for their groups, but the following questions on violent extremism remain: (a) Why are victims of suicide terrorism often innocent bystanders? (b) Why do terrorists seem motivated by ancient conflicts? We incorporate findings from the entitativity literature to provide insights into how perceptions of in-groups and out-groups are key processes influencing violent extremism.

Tightness-looseness across the 50 united states.

This research demonstrates wide variation in tightness-looseness (the strength of punishment and degree of latitude/permissiveness) at the state level in the United States, as well as its association with a variety of ecological and historical factors, psychological characteristics, and state-level outcomes. Consistent with theory and past research, ecological and man-made threats--such as a higher incidence of natural disasters, greater disease prevalence, fewer natural resources, and greater degree of external threat--predicted increased tightness at the state level. Tightness is also associated with higher trait conscientiousness and lower trait openness, as well as a wide array of outcomes at the state level. Compared with loose states, tight states have higher levels of social stability, including lowered drug and alcohol use, lower rates of homelessness, and lower social disorganization. However, tight states also have higher incarceration rates, greater discrimination and inequality, lower creativity, and lower happiness relative to loose states. In all, tightness-looseness provides a parsimonious explanation of the wide variation we see across the 50 states of the United States of America.

The Evolutionary Basis of Honor Cultures.

Around the globe, people fight for their honor, even if it means sacrificing their lives. This is puzzling from an evolutionary perspective, and little is known about the conditions under which honor cultures evolve. We implemented an agent-based model of honor, and our simulations showed that the reliability of institutions and toughness of the environment are crucial conditions for the evolution of honor cultures. Honor cultures survive when the effectiveness of the authorities is low, even in very tough environments. Moreover, the results show that honor cultures and aggressive cultures are mutually dependent in what resembles a predator-prey relationship described in the renowned Lotka-Volterra model. Both cultures are eliminated when institutions are reliable. These results have implications for understanding conflict throughout the world, where Western-based strategies are exported, often unsuccessfully, to contexts of weak institutional authority wherein honor-based strategies have been critical for survival.

Societal threat as a moderator of cultural group selection.

As scholars have rushed to either prove or refute cultural group selection (CGS), the debate lacks sufficient consideration of CGS's potential moderators. We argue that pressures for CGS are particularly strong when groups face ecological and human-made threat. Field, experimental, computational, and genetic evidence are presented to substantiate this claim.

The cultural dimension of tightness-looseness: An analysis of situational constraint in Estonia and Greece.

The importance of tightness-looseness as a dimension that explains a considerable amount of variance between cultures was demonstrated by Gelfand et al. (2011). Tight nations have many strong norms and a low tolerance of deviant behaviour, whereas loose nations have weak social norms and a high tolerance of deviant behaviour. The main aim of the current studies was to examine situational constraint in Estonia and Greece: that is, how the cultural dimension of tightness-looseness is manifested in everyday situations in those two countries. The findings of a questionnaire study (Study 1) suggested that, in general, there is higher constraint across everyday situations in Greece than in Estonia, but situational constraint in Greece is especially strong in school and organisational settings where people have hierarchically structured roles. The results of an observational study (Study 2) revealed a relatively high agreement between appropriateness of certain behaviours as judged by the respondents in Study 1 and the frequencies of observed behaviours in the two countries. Our findings suggest that the strength of situations may substantially vary both within and across cultures, and that the attitudes of the members about situational strength in their respective cultures are in concordance with observations of situations by neutral observers in how people in general behave in their culture.

Majority rule: Do minorities live in 'tighter' social worlds?

Exploring social norms through a diversity perspective, this review examines whether minorities live in 'tighter' worlds, wherein they are subject to stricter rules and punishments. Integrating research from psychology, economics, and organizational behavior, we first examine whether minorities are more likely to have tightness imposed on them-i.e., receive more monitoring and harsher penalties in response to norm violations, compared to their majority counterparts. Turning to the subjective experience of minority group members, we explore whether minorities are calibrated to these penalties and experience greater lived tightness-the feeling of being chronically surveilled, judged harshly, and fearing excessive punishment for wrongdoing. We suggest that both imposed and lived tightness contributes to power inequalities and patterns of segregation. This framework helps to organize disparate research streams investigating minorities' experience of social norms, and highlights unanswered questions about when, and why, minority group members feel more constrained by social rules, as well as the consequences of these experiences for their economic and psychological well-being.

Ecological priming: convergent evidence for the link between ecology and psychological processes.

This commentary describes the use of ecological priming methods to address the limitations of the correlational research discussed in the target article. We provide examples from our own work on cultural tightness-looseness to illustrate how we can bring ecological and societal conditions into the laboratory in order to study the impact of ecological threats on psychological processes experimentally.