Christopher von Rueden

University of Richmond | UR · Jepson School of Leadership Studies

This book provides a cutting-edge overview of emotion science from an evolutionary perspective. Part 1 outlines different ways of approaching the study of emotion; Part 2 covers specific emotions from an evolutionary perspective; Part 3 discusses the role of emotions in a variety of life domains; and Part 4 explores the relationship between emotion...

Status hierarchy likely exists in all human societies, whether pronounced or more subtle, and even in more egalitarian societies where resources are widely shared and overt status-seeking is actively policed. This chapter reviews models of the evolution of status hierarchy, including models from behavioral ecology as well as from evolutionary psych...

Much of the study of patriarchy focuses on its more proximate causes, including restrictive gender norms and institutionalized sexism. But where do restrictive gender norms and institutionalized sexism come from, and why are they so cross-culturally ubiquitous? We must also consider more ultimate causes of patriarchy, particularly the evolution of...

Variation in attachment quality was assessed in 92 one-to three-year-olds' (49 female, 43 male) attachment to their father, within and across two small-scale, subsistence populations: the Tsimane of lowland Bolivia (n = 29 dyads) and Tannese of Vanuatu (n = 63 dyads). Overall, the Tsimane and Tannese populations show similarity in the patterning of...

Politically egalitarian societies were likely more common in pre-history than in recent millenia. Why did societies become more hierarchical? Answers to this question remain debated, based on evidence largely drawn from archaeological case studies or comparison of societies from the ethnographic record. I suggest that modern small-scale societies t...

The niche-diversity hypothesis proposes that personality structure arises from the affordances of unique trait combinations within a society. It predicts that personality traits will be both more variable and differentiated in populations with more distinct social and ecological niches. Prior tests of this hypothesis in 55 nations suffered from pot...

Collective, synchronous music-making is far from ubiquitous across traditional, small-scale societies. We describe societies that lack collective music and offer hypotheses to help explain this cultural variation. Without identifying the factors that explain variation in collective music-making across these societies, theories of music evolution ba...

Social influence is distributed unequally between males and females in many mammalian societies. In human societies, gender inequality is particularly evident in access to leadership positions. Understanding why women historically and cross-culturally have tended to be under-represented as leaders within human groups and organizations represents a...

To negotiate conflict and navigate status hierarchy, individuals in many species form coalitions. We describe inter-personal conflicts and assess theories of coalition formation in a small-scale human society. Based on longitudinal and cross-sectional social network analysis of men in two communities of Tsimane forager–horticulturalists, we find ev...

We examine the opportunities children have for interacting with others and the extent to which they are the focus of others’ visual attention in five societies where extended family communities are the norm. We compiled six video-recorded datasets (two from one society) collected by a team of anthropologists and psychologists conducting long-term r...

The niche diversity hypothesis proposes that personality structure arises from the affordances of unique trait-combinations within a society. Prior tests of the hypothesis in 55 nations suffer from potential confounds associated with differences in the measurement properties of personality scales across groups. Using recently developed psychometric...

Decades of research conducted in Western, Educated, Industrialized, Rich, & Democratic (WEIRD) societies have led many scholars to conclude that the use of mental states in moral judgment is a human cognitive universal, perhaps an adaptive strategy for selecting optimal social partners from a large pool of candidates. However, recent work from a mo...

Evolutionary perspectives are part of any comprehensive explanation of leadership and, more generally, hierarchy formation in groups. This editorial describes contributions to a special issue on the theme of “The evolution and biology of leadership: A new synthesis”, and we reach four main conclusions. First, leadership has been a powerful force in...

The hypothesis of a human-universal personality structure is undermined by cross-cultural studies in small-scale societies. To explain cross-population differences in patterns of behavioral covariance, we proposed the niche diversity hypothesis, which holds that the degree of behavioral covariation within a population is inversely related to the nu...

We propose that networks of cooperation and allocation of social status co-emerge in human groups. We substantiate this hypothesis with one of the first longitudinal studies of cooperation in a preindustrial society, spanning 8 years. Using longitudinal social network analysis of cooperation among men, we find large effects of kinship, reciprocity...

Humans have likely spent the vast majority of our history as a species in relatively egalitarian, small-scale societies. This does not mean humans are by nature egalitarian. Rather, the ecological and demographic conditions common to small-scale societies favored the suppression of steep, dominance-based hierarchy and incentivized relatively shallo...

The structure of personality refers to the covariation among specific behavioral patterns in a population. Statistically derived models of personality-such as the Big Five or HEXACO models-usually assume that the covariance structure of personality characteristics is a human universal. Cross-cultural studies, however, have challenged this view, fin...

Existing approaches within leadership studies often share a bias towards industrialized societies and lack broader cross-cultural and ethological reference. Meanwhile, cross-cultural and evolutionary approaches within anthropology are actively working to unify research on leadership and followership across the biological and social sciences. This r...

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 meeti...

Correlations among distinct behaviors are foundational to personality science, but the field remains far from a consensus regarding the causes of such covariation. We advance a novel explanation for personality covariation, which views trait covariance as being shaped within a particular socioecology. We hypothesize that the degree of personality c...

Significance Much of human behavior results from a desire for social status. From an evolutionary perspective, answering the question of why we pursue status must consider how status affects reproduction, especially in nonindustrial societies with natural fertility. In a metaanalysis of 288 results from 33 nonindustrial populations, we find that st...

Significance It is widely considered a universal feature of human moral psychology that reasons for actions are taken into account in most moral judgments. However, most evidence for this moral intent hypothesis comes from large-scale industrialized societies. We used a standardized methodology to test the moral intent hypothesis across eight tradi...

Our paper [1] compared two competing hypotheses. The hypothesis that we label universalistic moral evaluation holds that a definitional feature of reasoning about moral rules is that, ceteris paribus, judgements of violations of rules concerning harm, rights or justice will be insensitive to spatial or temporal distance or the opinions of authority...

Observation of leadership in small-scale societies offers unique insights into the evolution of human collective action and the origins of sociopolitical complexity. Using behavioural data from the Tsimane forager-horticulturalists of Bolivia and Nyangatom nomadic pastoralists of Ethiopia, we evaluate the traits of leaders and the contexts in which...

Models of collective action infrequently account for differences across individuals beyond a limited set of strategies, ignoring variation in endowment (e.g. physical condition, wealth, knowledge, personality, support), individual costs of effort, or expected gains from cooperation. However, behavioural research indicates these inter-individual dif...

Human moral judgement may have evolved to maximize the individual's welfare given parochial culturally constructed moral systems. If so, then moral condemnation should be more severe when transgressions are recent and local, and should be sensitive to the pronouncements of authority figures (who are often arbiters of moral norms), as the fitness pa...

Sharing and exchange are common practices for minimizing food insecurity in rural populations. The advent of markets and monetization in egalitarian indigenous populations presents an alternative means of managing risk, with the potential impact of eroding traditional networks. We test whether market involvement buffers several types of risk and re...

Evolutionary theories of personality origins have stimulated much empirical research in recent years, but pertinent data from small-scale human societies have been in short supply. We investigate adaptively patterned personality variation among Tsimane’ forager-horticulturalists. Based on a consideration of cost-benefit tradeoffs that likely mainta...

We review research on the ultimate and proximate origins of variation along the extraversion continuum. After describing the cost-benefit tradeoffs that may have maintained variation in extraversion over human evolution, we consider the evidence bearing on multiple distinct evolutionary hypotheses regarding the causal underpinnings of such variatio...

Leadership is instrumental to resolution of collective action dilemmas, particularly in large, heterogeneous groups. Less is known about the characteristics or effectiveness of leadership in small-scale, homogeneous, and relatively egalitarian societies, in which humans have spent most of our existence. Among Tsimane' forager-horticulturalists of B...

Background and objectives: Low social status increases risk of disease due, in part, to the psychosocial stress that accompanies feeling subordinate or poor. Previous studies report that chronic stress and chronically elevated cortisol can impair cardiovascular and immune function. We test whether lower status is more benign in small-scale, relativ...

Since humans have lived in small-scale societies for the majority of their existence, investigation of the determinants and reproductive outcomes of status acquisition in these societies can help elucidate the origins of status psychology. In even the most egalitarian foragers and horticulturalists, interindividual differences in physical size, pro...

OBJECTIVES: To present an explanatory framework for depression in older adulthood in a small-scale society. We propose that depression is a consequence of functional disability, which can reduce subsistence productivity, and resource transfers within and across generations. Social conflict can disrupt risk management strategies and should also be a...

Successful collective action often depends on the presence of leaders, who bear greater responsibility than other group members for the logistics of coordination, monitoring of effort, and reward and punishment. Leaders may be expected to shoulder more risk, are vulnerable to retaliation from sanctioned group members, and suffer greater reputationa...

The maintenance of personality variation remains an unexplained puzzle in evolutionary biology. Despite evidence among non-humans that personality variation affects fitness, few data exist to assess the personality-fitness relationship in humans. Among Tsimane forager-horticulturalists (n = 632), we test whether personality traits (assessed using a...

Postmarital residence patterns in traditional human societies figure prominently in models of hominid social evolution with arguments for patrilocal human bands similar in structure to female-dispersal systems in other African apes. However, considerable flexibility in hunter-gatherer cultures has led to their characterization as primarily multiloc...

The five-factor model (FFM) of personality variation has been replicated across a range of human societies, suggesting the FFM is a human universal. However, most studies of the FFM have been restricted to literate, urban populations, which are uncharacteristic of the majority of human evolutionary history. We present the first test of the FFM in a...

The challenge hypothesis posits that acute increases in testosterone (T) during male-male competition enhance performance and survivability while limiting the physiological costs of consistently high T. Human challenge hypothesis research focuses on young men in industrial populations, who have higher baseline T levels than men in subsistence popul...

In small-scale societies, punishment of adults is infrequent and employed when the anticipated cost-to-benefit ratio is low, such as when punishment is collectively justified and administered. In addition, benefits may exceed costs when punishers have relatively greater physical and social capital and gain more from cooperation. We provide examples...

In many human societies, high male social status associates with higher fertility, but the means by which status increases lifetime fitness have not been systematically investigated. We analyse the pathways by which male status begets reproductive success in a small-scale, Amerindian society. Men who are more likely to win a dyadic physical confron...

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...

We present empirical measures of wealth inequality and its intergenerational transmission among four horticulturalist populations. Wealth is construed broadly as embodied somatic and neural capital, including body size, fertility and cultural knowledge, material capital such as land and household wealth, and relational capital in the form of coalit...

Origins of Egalitarianism Wealthy contemporary societies exhibit varying extents of economic inequality, with the Nordic countries being relatively egalitarian, whereas there is a much larger gap between top and bottom in the United States. Borgerhoff Mulder et al. (p. 682 ; see the Perspective by Acemoglu and Robinson ) build a bare-bones model de...

Children may be viewed as public goods whereby both parents receive equal genetic benefits yet one parent often invests more heavily than the other. We introduce a microeconomic framework for understanding household investment decisions to address questions concerning conflicts of interest over types and amount of work effort among married men and...

While social-status hierarchies are common to all human societies, status acquisition is relatively understudied in small-scale societies lacking significant material wealth or intergenerational inheritance. Among the Tsimane of Bolivia, a small-scale Amazonian society, we employ a photo-ranking methodology to determine the important predictors of...

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. He...

This paper assesses selective pressures that shaped primate life histories, with particular attention to the evolution of longer juvenile periods and increased brain sizes. We evaluate the effects of social complexity (as indexed by group size) and foraging complexity (as indexed by percent fruit and seeds in the diet) on the length of the juvenile...

Hunting performance may be one of the most important routes to high prestige or social status among men in hunter-gatherer societies. Higher social status based on hunting performance has been linked to higher biological fitness outcomes almost everywhere this relationship has been investigated. This paper explores the proximate pathways underlying...

Children may be viewed as public goods where both parents receive equal genetic benefits yet one parent often invests more heavily than the other. We introduce a micro-economic framework for understanding household investment decisions to address questions concerning conflicts of interest over types and amount of work effort among married men and w...