Fearful apes or emotional cooperative breeders?

The "fearful ape hypothesis" is interesting but is currently underspecified. We need more research on whether it is specific to fear, specific to humans (or even cooperative breeders in general), what is included in "fear," and whether these patterns would indeed evolve despite arms races to extract help from audiences. Specifying these will result in a more testable hypothesis.

Third-party punishers do not compete to be chosen as partners in an experimental game.

Third-party punishment is thought to act as an honest signal of cooperative intent and such signals might escalate when competing to be chosen as a partner. Here, we investigate whether partner choice competition prompts escalating investment in third-party punishment. We also consider the case of signalling via helpful acts to provide a direct test of the relative strength of the two types of signals. Individuals invested more in third-party helping than third-party punishment and invested more in both signals when observed compared to when investments would be unseen. We found no clear effect of partner choice (over and above mere observation) on investments in either punishment or helping. Third-parties who invested more than a partner were preferentially chosen for a subsequent Trust Game although the preference to interact with the higher investor was more pronounced in the help than in the punishment condition. Third-parties who invested more were entrusted with more money and investments in third-party punishment or helping reliably signalled trustworthiness. Individuals who did not invest in third-party helping were more likely to be untrustworthy than those who did not invest in third-party punishment. This supports the conception of punishment as a more ambiguous signal of cooperative intent compared to help.

Reciprocity creates a stake in one's partner, or why you should cooperate even when anonymous.

Why do we care so much for friends, even making sacrifices for them they cannot repay or never know about? When organisms engage in reciprocity, they have a stake in their partner's survival and wellbeing so the reciprocal relationship can persist. This stake (aka fitness interdependence) makes organisms willing to help beyond the existing reciprocal arrangement (e.g. anonymously). I demonstrate this with two mathematical models in which organisms play a prisoner's dilemma, and where helping keeps their partner alive and well. Both models shows that reciprocity creates a stake in partners' welfare: those who help a cooperative partner--even when anonymous--do better than those who do not, because they keep that cooperative partner in good enough condition to continue the reciprocal relationship. 'Machiavellian' cooperators, who defect when anonymous, do worse because their partners become incapacitated. This work highlights the fact that reciprocity and stake are not separate evolutionary processes, but are inherently linked.

Feelings of obligation are valuations of signaling-mediated social payoffs.

We extend Tomasello's framework by addressing the functional challenge of obligation. If the long-run social consequences of a decision are sufficiently costly, obligation motivates the actor to forgo potential immediate benefits in favor of long-term social interests. Thus, obligation psychology balances the downstream socially-mediated payoffs from a decision. This perspective can predict when and why obligation will be experienced.

Parasite stress and pathogen avoidance relate to distinct dimensions of political ideology across 30 nations.

People who are more avoidant of pathogens are more politically conservative, as are nations with greater parasite stress. In the current research, we test two prominent hypotheses that have been proposed as explanations for these relationships. The first, which is an intragroup account, holds that these relationships between pathogens and politics are based on motivations to adhere to local norms, which are sometimes shaped by cultural evolution to have pathogen-neutralizing properties. The second, which is an intergroup account, holds that these same relationships are based on motivations to avoid contact with outgroups, who might pose greater infectious disease threats than ingroup members. Results from a study surveying 11,501 participants across 30 nations are more consistent with the intragroup account than with the intergroup account. National parasite stress relates to traditionalism (an aspect of conservatism especially related to adherence to group norms) but not to social dominance orientation (SDO; an aspect of conservatism especially related to endorsements of intergroup barriers and negativity toward ethnic and racial outgroups). Further, individual differences in pathogen-avoidance motives (i.e., disgust sensitivity) relate more strongly to traditionalism than to SDO within the 30 nations.

Measuring delay discounting in a crowdsourced sample: An exploratory study.

Delay discounting is a measure of preferences for smaller immediate rewards over larger delayed rewards. Discounting has been assessed in many ways; these methods have variably and inconsistently involved measures of different lengths (single vs. multiple items), forced-choice methods, self-report methods, online and laboratory assessments, monetary and non-monetary compensation. The majority of these studies have been conducted in laboratory settings. However, over the past 20 years, behavioral data collection has increasingly shifted online. Usually, these experiments involve completing short tasks for small amounts of money, and are thus qualitatively different than experiments in the lab, which are typically more involved and in a strongly controlled environment. The present study aimed to determine how to best measure future discounting in a crowdsourced sample using three discounting measures (a single shot measure, the 27-item Kirby Monetary Choice Questionnaire, and a one-time Matching Task). We examined associations of these measures with theoretically related variables, and assessed influence of payment on responding. Results indicated that correlations between the discounting tasks and conceptually related measures were smaller than in prior laboratory experiments. Moreover, our results suggest providing monetary compensation may attenuate correlations between discounting measures and related variables. These findings suggest that incentivizing discounting measures changes the nature of measurement in these tasks.

State-dependent risk-taking.

Who takes risks, and when? The relative state model proposes two non-independent selection pressures governing risk-taking: need-based and ability-based. The need-based account suggests that actors take risks when they cannot reach target states with low-risk options (consistent with risk-sensitivity theory). The ability-based account suggests that actors engage in risk-taking when they possess traits or abilities that increase the expected value of risk-taking (by increasing the probability of success, enhancing payoffs for success or buffering against failure). Adaptive risk-taking involves integrating both considerations. Risk-takers compute the expected value of risk-taking based on their state-the interaction of embodied capital relative to one's situation, to the same individual in other circumstances or to other individuals. We provide mathematical support for this dual pathway model, and show that it can predict who will take the most risks and when (e.g. when risk-taking will be performed by those in good, poor, intermediate or extreme state only). Results confirm and elaborate on the initial verbal model of state-dependent risk-taking: selection favours agents who calibrate risk-taking based on implicit computations of condition and/or competitive (dis)advantage, which in turn drives patterned individual differences in risk-taking behaviour.

Why Hate the Good Guy? Antisocial Punishment of High Cooperators Is Greater When People Compete To Be Chosen.

When choosing social partners, people prefer good cooperators (all else being equal). Given this preference, people wishing to be chosen can either increase their own cooperation to become more desirable or suppress others' cooperation to make them less desirable. Previous research shows that very cooperative people sometimes get punished ("antisocial punishment") or criticized ("do-gooder derogation") in many cultures. Here, we used a public-goods game with punishment to test whether antisocial punishment is used as a means of competing to be chosen by suppressing others' cooperation. As predicted, there was more antisocial punishment when participants were competing to be chosen for a subsequent cooperative task (a trust game) than without a subsequent task. This difference in antisocial punishment cannot be explained by differences in contributions, moralistic punishment, or confusion. This suggests that antisocial punishment is a social strategy that low cooperators use to avoid looking bad when high cooperators escalate cooperation.

Broadening the role of "self-interest" in folk-economic beliefs.

We extend Boyer & Petersen's (B&P's) model of folk-economic beliefs (FEBs) by suggesting FEBs serve self-interest (broadly defined), which includes indirect benefits such as creating alliances, advancing self-beneficial ideologies, and signaling one's traits. By expanding the definition of self-interest, the model can predict who will hold what FEBs, which FEBs will propagate, when they will change, why, and in which direction.

The Relative State Model: Integrating Need-Based and Ability-Based Pathways to Risk-Taking.

Who takes risks, and why? Does risk-taking in one context predict risk-taking in other contexts? We seek to address these questions by considering two non-independent pathways to risk: need-based and ability-based. The need-based pathway suggests that risk-taking is a product of competitive disadvantage consistent with risk-sensitivity theory. The ability-based pathway suggests that people engage in risk-taking when they possess abilities or traits that increase the probability of successful risk-taking, the expected value of the risky behavior itself, and/or have signaling value. We provide a conceptual model of decision-making under risk-the relative state model-that integrates both pathways and explicates how situational and embodied factors influence the estimated costs and benefits of risk-taking in different contexts. This model may help to reconcile long-standing disagreements and issues regarding the etiology of risk-taking, such as the domain-generality versus domain-specificity of risk or differential engagement in antisocial and non-antisocial risk-taking.

Attractiveness biases are the tip of the iceberg in biological markets.

Physical attractiveness affects how one gets treated, but it is just a single component of one's overall "market value." One's treatment depends on other markers of market value, including social status, competence, warmth, and any other cues of one's ability or willingness to confer benefits on partners. To completely understand biased treatment, we must also incorporate these other factors.

Local competition increases people's willingness to harm others.

Why should organisms incur a cost in order to inflict a (usually greater) cost on others? Such costly harming behavior may be favored when competition for resources occurs locally, because it increases individuals' fitness relative to close competitors. However, there is no explicit experimental evidence supporting the prediction that people are more willing to harm others under local versus global competition. We illustrate this prediction with a game theoretic model, and then test it in a series of economic games. In these experiments, players could spend money to make others lose more. We manipulated the scale of competition by awarding cash prizes to the players with the highest payoffs per set of social partners (local competition) or in all the participants in a session (global competition). We found that, as predicted, people were more harmful to others when competition was local (Study 1). This result still held when people "earned" (rather than were simply given) their money (Study 2). In addition, when competition was local, people were more willing to harm ingroup members than outgroup members (Study 3), because ingroup members were the relevant competitive targets. Together, our results suggest that local competition in human groups not only promotes willingness to harm others in general, but also causes ingroup hostility.

The burden of proof for a cultural group selection account.

Richerson et al. establish cultural group selection as a plausible force in human social evolution. However, they do not demonstrate its causal precedence for any trait, let alone its "essentialness." To do so, they must show that a particular group trait was caused by cultural transmission, and directly caused differences in group fitness.

Local competition sparks concerns for fairness in the ultimatum game.

Humans reject uneven divisions of resources, even at personal cost. This is observed in countless experiments using the ultimatum game, where a proposer offers to divide a resource with a responder who either accepts the division or rejects it (whereupon both earn zero). Researchers debate why humans evolved a psychology that is so averse to inequity within partnerships. We suggest that the scale of competition is crucial: under local competition with few competitors, individuals reject low offers, because they cannot afford to be disadvantaged relative to competitors. If one competes against the broader population (i.e. global competition), then it pays to accept low offers to increase one's absolute pay-off. We support this intuition with an illustrative game-theoretical model. We also conducted ultimatum games where participants received prizes based on pay-offs relative to immediate partners (local competition) versus a larger group (global competition). Participants demanded higher offers under local competition, suggesting that local competition increases people's demands for fairness and aversion to inequality.

Pathways to abnormal revenge and forgiveness.

The target article's important point is easily misunderstood to claim that all revenge is adaptive. Revenge and forgiveness can overstretch (or understretch) the bounds of utility due to misperceptions, minimization of costly errors, a breakdown within our evolved revenge systems, or natural genetic and developmental variation. Together, these factors can compound to produce highly abnormal instances of revenge and forgiveness.

Fundamental freedoms and the psychology of threat, bargaining, and inequality.

Van de Vliert's findings may be explained by the psychology of threat and bargaining. Poor people facing extreme threats must cope by surrendering individual freedom in service of shared group needs. Wealthier people are more able to flee from threats and/or resist authoritarianism, so their leaders must concede greater freedom. Incorporating these factors (plus inequality) can sharpen researchers' predictions.

Greater traditionalism predicts COVID-19 precautionary behaviors across 27 societies.

People vary both in their embrace of their society's traditions, and in their perception of hazards as salient and necessitating a response. Over evolutionary time, traditions have offered avenues for addressing hazards, plausibly resulting in linkages between orientations toward tradition and orientations toward danger. Emerging research documents connections between traditionalism and threat responsivity, including pathogen-avoidance motivations. Additionally, because hazard-mitigating behaviors can conflict with competing priorities, associations between traditionalism and pathogen avoidance may hinge on contextually contingent tradeoffs. The COVID-19 pandemic provides a real-world test of the posited relationship between traditionalism and hazard avoidance. Across 27 societies (N = 7844), we find that, in a majority of countries, individuals' endorsement of tradition positively correlates with their adherence to costly COVID-19-avoidance behaviors; accounting for some of the conflicts that arise between public health precautions and other objectives further strengthens this evidence that traditionalism is associated with greater attention to hazards.

Proximate and ultimate causes of punishment and strong reciprocity.

While admirable, Guala's discussion of reciprocity suffers from a confusion between proximate causes (psychological mechanisms triggering behaviour) and ultimate causes (evolved function of those psychological mechanisms). Because much work on "strong reciprocity" commits this error, I clarify the difference between proximate and ultimate causes of cooperation and punishment. I also caution against hasty rejections of "wide readings" of experimental evidence.

Signaling benefits of partner choice decisions.

When deciding whom to choose for a cooperative interaction, two features of prospective partners are especially relevant: ability to provide benefits, and willingness to provide those benefits. Often, these traits are correlated. But, when ability and willingness are in conflict, people often indicate that they value willingness over ability, even when doing so results in immediate losses. Why would such behavior be favored by natural selection acting at the level of the individual? Across nine experimental studies (seven preregistered) and a mathematical model we explore one way of explaining this costly choice, demonstrating that choosing a willing over an able partner affords one a moral reputation and makes one more likely to be chosen as a cooperation partner. In fact, even people who choose an able over a willing partner for themselves prefer others who choose a willing over an able partner. Crucial to our model, we find that valuing willingness over ability is an honest signal of both higher levels of generosity in an economic game and lower levels of trait Machiavellianism. These findings provide the first extensive exploration of the signaling benefits of partner choice decisions. Furthermore, this work provides one explanation for why we choose those who are willing over those who are able, even at a cost to ourselves: By doing so, we in turn look like good potential partners. (PsycInfo Database Record (c) 2022 APA, all rights reserved).