On the evolved psychological mechanisms that make peace and reconciliation between groups possible.

If group norms and decisions foster peace, then understanding how norms and decisions arise becomes important. Here, we suggest that neither norms nor other forms of group-based decision making (such as offering restitution) can be adequately understood without simultaneously considering (i) what individual psychologies are doing and (ii) the dynamics these psychologies produce when interacting with each other.

On the Problems Solved by Cognitive Processes.

Cognitive scientists have focused too narrowly on the acquisition of data and on the methods to extract patterns from those data. We argue that a successful science of the mind requires widening our focus to include the problems being solved by cognitive processes. Frameworks that characterize cognitive processes in terms of instrumental problem-solving, such as those within the evolutionary social sciences, become necessary if we wish to discover more accurate descriptions of those processes.

More "us," less "them": An appeal for pluralism - and stand-alone computational theorizing - in our science of social groups.

The target article is an appeal to allow explicit computational theorizing into the study of social groups. Some commentators took this proposal and ran with it, some had questions about it, and some were confused or even put off by it. But even the latter did not seem to outright disagree - they thought the proposal was mutually exclusive with some other enterprise, when in fact it is not. Unfortunately, scientists studying social groups have not yet avoided the thread-bare trope of the blind men studying the different parts of the elephant: We see mutual exclusivity when we should see complementarity. I hope we can all take the next steps of examining how the different enterprises and approaches within our area of research might all fit together into a unified whole.

A (failed) attempt to falsify the alliance hypothesis of racial categorization: Racial categorization is not reduced when crossed with a nonalliance category.

Why do humans implicitly categorize individuals by their race? The alliance hypothesis-which argues that racial categorization is a byproduct of evolved information-processing systems in the mind for keeping track of alliances-has been the most successful causal account of racial categorization to date, amassing a large number of uniformly successful findings across a number of different papers. These findings show that when race is crossed with (i.e., is not predictive of) alliance membership, participants' categorization by race is reduced or eliminated, whereas categorization by other dimensions, such as sex or age, remain relatively unaffected. These results have been taken to mean that race is an alliance proxy within the mind, and can be superseded when better alliance information is provided. However, a counterhypothesis remains that cannot only account for all of the data observed in this past work, but could also undermine the entire theoretical interpretation of those data, which is that race may simply be a more flexible social category-meaning that categorization by race will be lowered by any crossed category, even categories that are not alliances. This counterhypothesis has never been tested against. The study reported here does so, examining if a contextually relevant crossed category that is not an alliance also reduces racial categorization. Results demonstrate that it does not: neither race nor sex (between-subjects) was affected when crossed with this nonalliance category. The race-is-just-more-flexible counterhypothesis is excluded as alternative causal account of the alliance hypothesis findings on racial categorization. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Why Evolutionary Psychology Should Abandon Modularity.

A debate surrounding modularity-the notion that the mind may be exclusively composed of distinct systems or modules-has held philosophers and psychologists captive for nearly 40 years. Concern about this thesis-which has come to be known as the massive modularity debate-serves as the primary grounds for skepticism of evolutionary psychology's claims about the mind. In this article we argue that the entirety of this debate, and the very notion of massive modularity itself, is ill-posed and confused. In particular, it is based on a confusion about the level of analysis (or reduction) at which one is approaching the mind. Here we provide a framework for clarifying at what level of analysis one is approaching the mind and explain how a systemic failure to distinguish between different levels of analysis has led to profound misunderstandings of not only evolutionary psychology but also of the entire cognitivist enterprise of approaching the mind at the level of the mechanism. We furthermore suggest that confusions between different levels of analysis are endemic throughout the psychological sciences-extending well beyond issues of modularity and evolutionary psychology. Therefore, researchers in all areas should take preventive measures to avoid this confusion in the future.

Toward a computational theory of social groups: A finite set of cognitive primitives for representing any and all social groups in the context of conflict.

We don't yet have adequate theories of what the human mind is representing when it represents a social group. Worse still, many people think we do. This mistaken belief is a consequence of the state of play: Until now, researchers have relied on their own intuitions to link up the concept social group on the one hand and the results of particular studies or models on the other. While necessary, this reliance on intuition has been purchased at a considerable cost. When looked at soberly, existing theories of social groups are either (i) literal, but not remotely adequate (such as models built atop economic games), or (ii) simply metaphorical (typically a subsumption or containment metaphor). Intuition is filling in the gaps of an explicit theory. This paper presents a computational theory of what, literally, a group representation is in the context of conflict: It is the assignment of agents to specific roles within a small number of triadic interaction types. This "mental definition" of a group paves the way for a computational theory of social groups - in that it provides a theory of what exactly the information-processing problem of representing and reasoning about a group is. For psychologists, this paper offers a different way to conceptualize and study groups, and suggests that a non-tautological definition of a social group is possible. For cognitive scientists, this paper provides a computational benchmark against which natural and artificial intelligences can be held.

The correct way to test the hypothesis that racial categorization is a byproduct of an evolved alliance-tracking capacity.

The project of identifying the cognitive mechanisms or information-processing functions that cause people to categorize others by their race is one of the longest-standing and socially-impactful scientific issues in all of the behavioral sciences. This paper addresses a critical issue with one of the few hypotheses in this area that has thus far been successful-the alliance hypothesis of race-which had predicted a set of experimental circumstances that appeared to selectively target and modify people's implicit categorization of others by their race. Here, we will show why the evidence put forward in favor of this hypothesis was not in fact evidence in support of the hypothesis, contrary to common understanding. We will then provide the necessary and crucial tests of the hypothesis in the context of conflictual alliances, determining if the predictions of the alliance hypothesis of racial categorization in fact hold up to experimental scrutiny. When adequately tested, we find that indeed categorization by race is selectively reduced when crossed with membership in antagonistic alliances-the very pattern predicted by the alliance hypothesis. This finding provides direct experimental evidence that the human mind treats race as proxy for alliance membership, implying that racial categorization does not reflect attention to physical features per se, but rather to social relationships.

Three-month-old human infants use vocal cues of body size.

Differences in vocal fundamental (F0) and average formant (Fn) frequencies covary with body size in most terrestrial mammals, such that larger organisms tend to produce lower frequency sounds than smaller organisms, both between species and also across different sex and life-stage morphs within species. Here we examined whether three-month-old human infants are sensitive to the relationship between body size and sound frequencies. Using a violation-of-expectation paradigm, we found that infants looked longer at stimuli inconsistent with the relationship-that is, a smaller organism producing lower frequency sounds, and a larger organism producing higher frequency sounds-than at stimuli that were consistent with it. This effect was stronger for fundamental frequency than it was for average formant frequency. These results suggest that by three months of age, human infants are already sensitive to the biologically relevant covariation between vocalization frequencies and visual cues to body size. This ability may be a consequence of developmental adaptations for building a phenotype capable of identifying and representing an organism's size, sex and life-stage.

Constituents of political cognition: Race, party politics, and the alliance detection system.

Research suggests that the mind contains a set of adaptations for detecting alliances: an alliance detection system, which monitors for, encodes, and stores alliance information and then modifies the activation of stored alliance categories according to how likely they will predict behavior within a particular social interaction. Previous studies have established the activation of this system when exposed to explicit competition or cooperation between individuals. In the current studies we examine if shared political opinions produce these same effects. In particular, (1) if participants will spontaneously categorize individuals according to the parties they support, even when explicit cooperation and antagonism are absent, and (2) if party support is sufficiently powerful to decrease participants' categorization by an orthogonal but typically-diagnostic alliance cue (in this case the target's race). Evidence was found for both: Participants spontaneously and implicitly kept track of who supported which party, and when party cross-cut race-such that the race of targets was not predictive of party support-categorization by race was dramatically reduced. To verify that these results reflected the operation of a cognitive system for modifying the activation of alliance categories, and not just socially-relevant categories in general, an identical set of studies was also conducted with in which party was either crossed with sex or age (neither of which is predicted to be primarily an alliance category). As predicted, categorization by party occurred to the same degree, and there was no reduction in either categorization by sex or by age. All effects were replicated across two sets of between-subjects conditions. These studies provide the first direct empirical evidence that party politics engages the mind's systems for detecting alliances and establish two important social categorization phenomena: (1) that categorization by age is, like sex, not affected by alliance information and (2) that political contexts can reduce the degree to which individuals are represented in terms of their race.

Not by strength alone : children's conflict expectations follow the logic of the asymmetric war of attrition.

The Asymmetric War of Attrition (AWA) model of animal conflict in evolutionary biology (Maynard Smith and Parker in Nature, 246, 15-18, 1976) suggests that an organism's decision to withdraw from a conflict is the result of adaptations designed to integrate the expected value of winning, discounted by the expected costs that would be incurred by continuing to compete, via sensitivity to proximate cues of how quickly each side can impose costs on the other (Resource Holding Potential), and how much each side will gain by winning. The current studies examine whether human conflict expectations follow the formalized logic of this model. Children aged 6-8 years were presented with third-party conflict vignettes and were then asked to predict the likely winner. Cues of ownership, hunger, size, strength, and alliance strength were systematically varied across conditions. Results demonstrate that children's expectations followed the logic of the AWA model, even in complex situations featuring multiple, competing cues, such that the actual relative costs and benefits that would accrue during such a conflict were reflected in children's expectations. Control conditions show that these modifications to conflict expectations could not have resulted from more general experimental artifacts or demand characteristics. To test the selectivity of these effects to conflict, expectations of search effort were also assessed. As predicted, they yielded a different pattern of results. These studies represent one of the first experimental tests of the AWA model in humans and suggest that future research on the psychology of ownership, conflict, and value may be aided by formalized models from evolutionary biology.

The content of our cooperation, not the color of our skin: an alliance detection system regulates categorization by coalition and race, but not sex.

Humans in all societies form and participate in cooperative alliances. To successfully navigate an alliance-laced world, the human mind needs to detect new coalitions and alliances as they emerge, and predict which of many potential alliance categories are currently organizing an interaction. We propose that evolution has equipped the mind with cognitive machinery that is specialized for performing these functions: an alliance detection system. In this view, racial categories do not exist because skin color is perceptually salient; they are constructed and regulated by the alliance system in environments where race predicts social alliances and divisions. Early tests using adversarial alliances showed that the mind spontaneously detects which individuals are cooperating against a common enemy, implicitly assigning people to rival alliance categories based on patterns of cooperation and competition. But is social antagonism necessary to trigger the categorization of people by alliance--that is, do we cognitively link A and B into an alliance category only because they are jointly in conflict with C and D? We report new studies demonstrating that peaceful cooperation can trigger the detection of new coalitional alliances and make race fade in relevance. Alliances did not need to be marked by team colors or other perceptually salient cues. When race did not predict the ongoing alliance structure, behavioral cues about cooperative activities up-regulated categorization by coalition and down-regulated categorization by race, sometimes eliminating it. Alliance cues that sensitively regulated categorization by coalition and race had no effect on categorization by sex, eliminating many alternative explanations for the results. The results support the hypothesis that categorizing people by their race is a reversible product of a cognitive system specialized for detecting alliance categories and regulating their use. Common enemies are not necessary to erase important social boundaries; peaceful cooperation can have the same effect.

Coalitional psychology on the playground: reasoning about indirect social consequences in preschoolers and adults.

Surprisingly little is known about how relationship information is used predict others' behavior. We examine a key element of this ability-how relationship information is used to anticipate how others will react to events in which they are not directly involved. This requires both using relationship information to modify expected reactions (e.g., friends may be more responsive than acquaintances) and also inference rules for restricting the class of reactions that may be felt or experienced on behalf of others (e.g., uninvolved friends may become angry but cannot become dizzy). These capacities were examined in both preschoolers and adults. Two different events were presented; one that would elicit anger from those who were involved and one that would elicit dizziness. For both sets of participants, cues to relationship status had a strong impact on anger expectations (uninvolved friends were expected to be more angry than uninvolved classmates), but had no effect dizziness expectations (neither uninvolved friends nor classmates were expected to be dizzy). Follow-up analyses also revealed a developmental difference. Adults made distinctions within the uninvolved friends category-expecting friends to be less angry at their own friend, and that levels of anger would vary according to their friend's role within the social conflict-whereas preschoolers did not. These results demonstrate that by the early preschool years sophisticated inference rules already govern the expected reactions of uninvolved others, but that important developmental differences also remain. These results also indicate that relationship representations are inference engines for anticipating others' behavior and reactions, not simply static containers for sorting people into categories.

The elementary dynamics of intergroup conflict and revenge.

The psychology underlying revenge in an intergroup context is built around a small handful of recurrent interaction types. Analyzing the cost/benefit calculations of each agent's role within these interaction types provides a more precise way to characterize intergroup conflict and revenge. This in turn allows for more precise models of the psychology of intergroup conflict to be proposed and tested.