Physical formidability and acceptance of police violence

Individuals whose threats of force are more effective, such as those with greater bodily formidability, have advantages when the social environment condones violence. This benefit shapes incentives regarding norms and preferences allowing aggressive behavior. More physically imposing people may, in particular, be likelier to approve of police use of violent tactics, one recent social flashpoint concerning attitudes to physical aggression. Archival data concerning more than 1600 respondents to the 2014 and 2018 iterations of the United States' General Social Survey confirm this hypothesis, with taller respondents (as the proxy for formidability) likelier to approve of police officers hitting male citizens in several circumstances, as well as corporal criminal-justice punishment in the form of the death penalty. Black respondents show less relationship between physical size and condoning of violent policing.     

An evolutionary model of low mood states

It has been suggested that low mood in humans is an adaptive response to unfavourable circumstances, and that the anhedonia, pessimism and fatigue that often accompany it function to minimise risk until circumstances improve. While this is plausible, it would be possible to make the opposite prediction equally plausibly: individuals in bad circumstances should take greater risks in order to improve their situations. Here, I present a simple analytical model adapted from the risk-sensitive foraging literature. It shows that in dire states, individuals should be risk-prone, in poor states, risk-averse, and in good states, risk-prone again. I discuss how the various kinds of mood state observed in humans might be understood as mechanisms for adaptively adjusting behavioural risk-taking to the current situation.     

Who dares, wins

Heroism is apparently nonadaptive in Darwinian terms, so why does it exist at all? Risk-taking and heroic behavior are predominantly male tendencies, and literature and legend reflect this. This study explores the possibility that heroism persists in many human cultures owing to a female preference for risk-prone rather than risk-averse males as sexual partners, and it suggests that such a preference may be exploited as a male mating strategy. It also attempts to quantify the relative influences of altruism and bravery in the evolution of heroism. Our study found that females do prefer risk-prone brave males to risk-averse non-brave males, and that men are aware of this preference. Bravery in a male was shown to be the stronger factor influencing female choice of short-term partners, long-term partners, and male friends, with altruism playing a lesser part in their choice. Altruism was deemed important in long-term relationships and friendships, but for short-term liaisons, non-altruists were preferred to altruists. Heroism may therefore have evolved owing to a female preference for brave, risk-prone males because risk-taking acts as an honest cue for "good genes." Altruism was judged to be a less influential factor in the evolution of heroism than bravery and a demonstrated willingness to take risks.     

Weapons make the man (larger): formidability is represented as size and strength in humans

In order to determine how to act in situations of potential agonistic conflict, individuals must assess multiple features of a prospective foe that contribute to the foe's resource-holding potential, or formidability. Across diverse species, physical size and strength are key determinants of formidability, and the same is often true for humans. However, in many species, formidability is also influenced by other factors, such as sex, coalitional size, and, in humans, access to weaponry. Decision-making involving assessments of multiple features is enhanced by the use of a single summary variable that encapsulates the contributions of these features. Given both a) the phylogenetic antiquity of the importance of size and strength as determinants of formidability, and b) redundant experiences during development that underscore the contributions of size and strength to formidability, we hypothesize that size and strength constitute the conceptual dimensions of a representation used to summarize multiple diverse determinants of a prospective foe's formidability. Here, we test this hypothesis in humans by examining the effects of a potential foe's access to weaponry on estimations of that individual's size and strength. We demonstrate that knowing that an individual possesses a gun or a large kitchen knife leads observers to conceptualize him as taller, and generally larger and more muscular, than individuals who possess only tools or similarly mundane objects. We also document that such patterns are not explicable in terms of any actual correlation between gun ownership and physical size, nor can they be explained in terms of cultural schemas or other background knowledge linking particular objects to individuals of particular size and strength. These findings pave the way for a fuller understanding of the evolution of the cognitive systems whereby humans--and likely many other social vertebrates--navigate social hierarchies.     

Male facial width is associated with death by contact violence: narrow-faced males are more likely to die from contact violence

Male facial width-to-height ratio (bizygomatic width scaled for face height) is a testosterone-linked trait predictive of reactive aggression, exploitative behavior, cheating, deception, and dominance. We tested whether facial width was systematically related to cause of death in a forensic sample. We hypothesized that wider-faced males, being more aggressive and robust, would be less likely than narrower-faced males to die from contact violence (stabbed, strangled, or bludgeoned to death) compared with other forms of homicide. We tested this hypothesis in a forensic data sample covering 523 male and 339 female skeletons. In these data, men with narrower faces were more likely to have died as a consequence of homicides involving direct physical contact than men with wider faces. No such effect was found for women. This effect was found when considering all causes of mortality and when limiting the sample to homicides. This finding suggests that wider-faced males are less likely to die from male–male physical violence, perhaps because of their formidability. Our findings are discussed with reference to the previous literature indicating that facial width-to-height ratio is a marker for male dominance.     

Contextual factors that heighten interest in coalitional alliances with men possessing formidable facial structures

Individuals use facial width-to-height ratio (fWHR) to infer men's formidability. We hypothesized that fWHR assessments would form a basis for men's coalitional value, with high-fWHR men being valuable in roles requiring physical strength. Five studies (N = 1323) tested how perceptions of formidability influence coalitional decisions. In addition to replicating previous findings indicating a preference for high-fWHR men in tasks requiring strength (Study 1), the formidability inference most associated with this high-fWHR preference was perceived strength and not aggressiveness (Studies 2a, 2b). Two pre-registered studies showed that activating competitive motivations increased preferences for high-fWHR allies (Study 3), though this preference appeared driven by a tolerance for high-fWHR men rather than an interest (Study 4). Findings provide evidence for how inferences of fWHR shape interpersonal preferences based on social contexts.     

Adaptations in humans for assessing physical strength from the voice

Recent research has shown that humans, like many other animals, have a specialization for assessing fighting ability from visual cues. Because it is probable that the voice contains cues of strength and formidability that are not available visually, we predicted that selection has also equipped humans with the ability to estimate physical strength from the voice. We found that subjects accurately assessed upper-body strength in voices taken from eight samples across four distinct populations and language groups: the Tsimane of Bolivia, Andean herder-horticulturalists and United States and Romanian college students. Regardless of whether raters were told to assess height, weight, strength or fighting ability, they produced similar ratings that tracked upper-body strength independent of height and weight. Male voices were more accurately assessed than female voices, which is consistent with ethnographic data showing a greater tendency among males to engage in violent aggression. Raters extracted information about strength from the voice that was not supplied from visual cues, and were accurate with both familiar and unfamiliar languages. These results provide, to our knowledge, the first direct evidence that both men and women can accurately assess men''s physical strength from the voice, and suggest that estimates of strength are used to assess fighting ability.     

A thin slice of violence: distinguishing violent from nonviolent sex offenders at a glance

A growing body of literature in evolutionary psychology suggests that person perception processes are adaptively tuned. The current investigation tested the hypothesis that people would be able to detect a propensity for violence in other people, based only on a brief glance at their face. Participants estimated the propensity for violence in 87 registered sex offenders after seeing photos of them for 2 s each. Estimated likelihood of violence was significantly related to actual violent history, suggesting that violent tendencies can be accurately inferred from a brief look at a person's face. Cues indicative of high masculinity and high levels of male sex hormones (heavy brow, general facial masculinity, high physical strength, younger age) were related to accurate judgments. Other cues such as facial emotion and good grooming were not associated with an actual history of violence, but nevertheless correlated with raters' judgments. Although there were no sex differences in accuracy, on average women thought targets were more violent than men did. Findings speak to the accuracy and efficiency with which people can detect potential threats to physical well-being.     

Marching into battle: synchronized walking diminishes the conceptualized formidability of an antagonist in men

Paralleling behaviours in other species, synchronized movement is central to institutionalized collective human activities thought to enhance cooperation, and experiments demonstrate that synchrony has this effect. The influence of synchrony on cooperation may derive from an evolutionary history wherein such actions served to signal coalitional strength to both participants and observers—including adversaries. If so, then synchronous movement should diminish individuals'' estimations of a foe''s formidability. Envisioned physical size and strength constitute the dimensions of a representation that summarizes relative fighting capacity. Experiencing synchrony should therefore lead individuals to conceptualize an antagonist as smaller and weaker. We found that men who walked synchronously with a male confederate indeed envisioned a purported criminal as less physically formidable than did men who engaged in this task without synchronizing.     

Physical strength predicts political violence

Research has revealed an association between individual physical strength and attitudinal support for modern war. Physical strength of one individual has an infinitesimal effect on the outcomes of state-level aggression involving large-scale armies and complex military technology. The fact that stronger individuals do support such aggression hints at an evolved psychology specialized for small-scale coalitional aggression, where strength of coalition members non-negligibly contribute to the net coalition strength. Here, I examined whether strength also accounts for participation in modern political aggression, as contrasted to mere support. Given that contemporary political aggression primarily occurs within—not between—states, I focused on intra-state forms of political violence, specifically violent antigovernment protests. To enhance external and ecological validity, I relied on large probability samples from both non-WEIRD and WEIRD countries experiencing political violence (N = 6283; interviewees were quota-sampled from YouGov online panels to generate representative samples of online adult populations). Multinational analyses revealed that self-perceived strength significantly predicts intentions to participate in political violence and self-reported participation, and that this association is stronger among young interviewees, but not among men (compared to women). The predictive power of strength was modest but comparable to that of gender, an established predictor of aggression. I discuss why the fact that strength—a physiological variable—relates to political violence—a complex modern phenomenon—is remarkable. Subsequently, I suggest a new research agenda that draws on insights from evolutionary research to study modern political violence.     

An integrative study of facultative personality calibration

The theory of facultative calibration, which explains personality differences as responses to variation in other phenotypic traits of individuals, received mixed results throughout the last years. Whereas there is strong evidence that individual differences in human behavior are correlated with the self-perception of other traits, it still needs to be questioned whether they are also adjusted to objective differences in body condition (i.e. formidability). In two independent studies (N₁?=?119 men and 124 women, N₂?=?165 men) we tested hypotheses of facultative personality calibration in an integrative way, assessing various outcomes of previous studies in the same samples (including Anger Proneness, Extraversion, Neuroticism, Narcissism, Shyness, Vengefulness, and Sociosexual Orientation). Formidability was derived from assessments of physical strength and various anthropometric measures from full-body 3D scans and paired with measures of self-perceived and other-rated physical attractiveness (based on rotating morphometric 3D body models and facial photographs). We could replicate positive correlations with self-perceived attractiveness across outcomes, though these were not corroborated by more objective assessments of attractiveness: an effect of other-rated attractiveness was clearly not supported in our results for either sex, regardless of the personality outcome. Anthropometric measures and physical strength were also largely unrelated to personality, with the exception of Extraversion, Utility of Personal Aggression, and Sociosexual Orientation. While the two samples differed in their results for domain-level Extraversion, at least the Extraversion facets Activity and Assertiveness were related to strength and masculinity in men. For Sociosexual Orientation the results of our two samples varied more substantially, a positive association was only present in Study 2. Future studies need to clarify whether formidability, potentially an indicator of genetic quality for males, enhances their orientation and success in short-term mating. Furthermore we propose longitudinal twin-difference studies as means to evaluate the theory of personality recalibration in a more controlled manner.     

Violence Affects Physical and Mental Health Differently: The General Population Based Troms? Study

This general population-based study examined associations between violence and mental health, musculoskeletal pain, and early disability pension. The prevalence and consequences of good vs. poor adjustment (resilience vs. vulnerability) following encounters with violence were also examined. Data were based on the sixth wave of the “Tromsø Study” (N = 12,981; 65.7% response rate, 53.4% women, M-age = 57.5 years, SD-age = 12.7 years). Self-reported data on psychological (threats) and physical violence (beaten/kicked), mental health (anxiety/depression), musculoskeletal pain (MSP), and granting of disability pension (DP) were collected. Men suffered more violent events during childhood than women did, and vice versa during adulthood. Psychological violence implied poorer mental health and slightly more MSP than physical violence. The risk of MSP was highest for violence occurring during childhood in women and during the last year for men. A dose-response relationship between an increasing number of violent encounters and poorer health was observed. About 58% of individuals reported no negative impact of violence (hence, resilience group), whereas 42% considered themselves as more vulnerable following encounters with violence. Regression analyses indicated comparable mental health but slightly more MSP in the resilience group compared to the unexposed group, whereas the vulnerable group had significantly worse health overall and a higher risk of early granting of DP. Resilience is not an all-or-nothing matter, as physical ailments may characterize individuals adapting well following encounters with violence.     

Male voice pitch mediates the relationship between objective and perceived formidability

Acoustic signals function in intrasexual mating competition in a wide variety of species, including humans. The low voice pitch of human males has been proposed to represent an honest signal of formidability. Although voice pitch in men affects perceptions of size and dominance, it is relatively weakly associated with objective measures of formidability such as body size and strength. As a result, some authors have argued that low male voice pitch is not a valid signal of formidability but is deceptive and salient only because it hijacks a tendency to perceive lower frequency sounds as emanating from larger sources. In this paper, we consider theoretical and empirical issues associated with this perceptual exploitation hypothesis and ask whether male voice pitch transmits information about formidability. We utilize mediation models to investigate whether male voice pitch is an honest signal of formidability in data collected from university students in the U.S. (n = 231 male speakers, 565 male raters) and Canada (n = 74 male speakers, 108 female raters, 65 male raters). In both data sets, male voice pitch mediated the relationship between objective (measured by height) and perceived formidability. Collectively, these results indicate that men’s voice pitch transmits information about formidability from signaler to receiver.     

Sex differences in political leadership in an egalitarian society

We test the contribution of sex differences in physical formidability, education, and cooperation to the acquisition of political leadership in a small-scale society. Among forager-farmers from the Bolivian Amazon, we find that men are more likely to exercise different forms of political leadership, including verbal influence during community meetings, coordination of community projects, and dispute resolution. We show that these differences in leadership are not due to gender per se but are associated with men's greater number of cooperation partners, greater access to schooling, and greater body size and physical strength. Men's advantage in cooperation partner number is tied to their participation in larger groups and to the opportunity costs of women's intrahousehold labor. We argue these results highlight the mutual influence of sexual selection and the sexual division of labor in shaping how women and men acquire leadership.     

Facial cues to physical strength increase attractiveness but decrease aggressiveness assessments in male Maasai of Northern Tanzania

Male physical formidability may reflect capacities to provision and protect, resource holding potential, and social status. Handgrip strength (HGS) is a robust measure of overall muscular strength and function that correlates positively with ratings of male facial attractiveness and dominance. Here, we examine strength, attractiveness, and aggressiveness assessments as a function of facial cues to HGS in a sample of male Maasai of Northern Tanzania. Adult Maasai (56 women, 40 men) rated three strength-calibrated facial morphs of Maasai men. These morphs were constructed by performing a geometric morphometric shape regression on HGS using digital images of 54 men (20–29 years). Participants judged facial morphs calibrated to greater HGS higher on strength and attractiveness, but lower on aggressiveness. The accurate assessment of male Maasai physical strength from facial cues and the corresponding attractiveness assessments of strength cues are consistent with evolutionary predictions and previous research. The situation is less clear for the association of facial strength cues with the assessment of aggression. Future research should consider the possibility of a (feature-based) perceptual overgeneralization, especially in the interpretation of facial aggressiveness judgments, in addition to population-specific influences, and distinguish them from facial cues that indicate behavioral dispositions. Collectively, the findings of the present study corroborate the suggestion that the Maasai are sensitive to facial cues of strength and use these cues in social assessments.     

Is sociopolitical egalitarianism related to bodily and facial formidability in men?

Social bargaining models predict that men should calibrate their egalitarian attitudes to their formidability and/or attractiveness. A simple social bargaining model predicts a direct negative association between formidability/attractiveness and egalitarianism, whereas a more complex model predicts an association moderated by wealth. Our study tested both models with 171 men, using two sociopolitical egalitarianism measures: social dominance orientation and support for redistribution. Predictors included bodily formidability and attractiveness and four facial measures (attractiveness, dominance, masculinity, and width-to-height ratio). We also controlled for time spent lifting weights, and experimentally manipulated self-perceived formidability in an attempt to influence egalitarianism. Both the simple and complex social bargaining models received partial support: sociopolitical egalitarianism was negatively related to bodily formidability, but unrelated to other measures of bodily/facial formidability/attractiveness; and a formidability-wealth interaction did predict variance in support for redistribution, but the nature of this interaction differed somewhat from that reported in previous research. Results of the experimental manipulation suggested that egalitarianism is unaffected by self-perceived formidability in the immediate short-term. In sum, results provided some support for both the simple and complex social bargaining models, but suggested that further research is needed to explain why male formidability/attractiveness and egalitarianism are so often negatively related.     

Human adaptations for the visual assessment of strength and fighting ability from the body and face

Selection in species with aggressive social interactions favours the evolution of cognitive mechanisms for assessing physical formidability (fighting ability or resource-holding potential). The ability to accurately assess formidability in conspecifics has been documented in a number of non-human species, but has not been demonstrated in humans. Here, we report tests supporting the hypothesis that the human cognitive architecture includes mechanisms that assess fighting ability-mechanisms that focus on correlates of upper-body strength. Across diverse samples of targets that included US college students, Bolivian horticulturalists and Andean pastoralists, subjects in the US were able to accurately estimate the physical strength of male targets from photos of their bodies and faces. Hierarchical linear modelling shows that subjects were extracting cues of strength that were largely independent of height, weight and age, and that corresponded most strongly to objective measures of upper-body strength-even when the face was all that was available for inspection. Estimates of women's strength were less accurate, but still significant. These studies are the first empirical demonstration that, for humans, judgements of strength and judgements of fighting ability not only track each other, but accurately track actual upper-body strength.     

Formidability assessment mechanisms: Examining their speed and automaticity

Throughout vertebrate evolution, asymmetries in the ability to inflict costs on others (i.e., formidability) have determined the outcomes of contests over limited resources. Therefore, natural selection would have favored mechanisms designed to efficiently and accurately estimate the formidability of conspecifics. Although previous research has provided evidence for the existence of adaptations for formidability assessment, the design features of these mechanisms have not been fully examined. In the current study, participants underwent a battery of tasks to test hypotheses regarding the speed and automaticity of formidability assessment mechanisms. Results suggest that formidability is automatically and rapidly tracked and assessed from visual cues. With a few interesting exceptions, characteristics of the raters (N = 187) and targets (N = 64) did not influence these assessments. Additionally, we present eye–tracking data to highlight the salience of upper–body musculature as a cue to physical strength. Taken together, these findings bolster and extend evidence for formidability assessment mechanisms in humans.     

Patrimony and the Evolution of Risk-Taking

The propensity to make risky choices has a genetic component, and recent studies have identified several specific genes that contribute to this trait. Since risk-taking often appears irrational or maladaptive, the question arises how (or if) natural selection favors risk-taking. Here we show, using a stochastic simulation of selection between two hypothetical species, “R” (risk-seeking) and “A” (risk-averse) that, when expected reproductive fitness of the individual is unaffected by the making of the risky choice (winnings balanced by losses) natural selection (taken to the point of extinction) favors the risk-averse species. However, the situation is entirely reversed if offspring are permitted to inherit a small fraction of the parent''s increased or decreased fitness acquired through risk-taking. This seemingly Lamarckian form of inheritance actually corresponds to the human situation when property or culture are transmitted in families. In the presence of this “cultural inheritance”, the long-shot risk-taking species was overwhelmingly favored, even when 90% of individuals were rendered sterile by a losing choice. Given this strong effect in a minimal model, it is important to consider the co-evolution of genes and culture when interpreting the genetics of risk-taking. This conclusion applies, in principle, to any species where parental resources can directly affect the fecundity of offspring. It might also be relevant to the effects of epigenetic inheritance, if the epigenetic state of zygotes can be affected by parental experiences.