Journal article

Norenzayan, A., A. F. Shariff, W. M. Gervais, A. Willard, R. McNamara, E. Slingerland, and J. Henrich. “The Cultural Evolution of Prosocial Religions.” Behavioral and Brain Sciences 39 (2016): 1-19. Online Version
McNamara, Rita Anne, Ara Norenzayan, and Joseph Henrich. “Supernatural punishment, in-group biases, and material insecurity: Experiments and Ethnography from Yasawa, Fiji.” Religion, Brain & Behavior 6, no. 1 (2016): 34-55. Online Version PDF
Muthukrishna, Michael, Thomas Joshua Henry Morgan, and Joseph Henrich. “The When and Who of Social Learning and Conformist Transmission.” Evolution and Human Behavior 37, no. 1 (2016): 10-20. PDF
Henrich, Joseph, Maciej Chudek, and Robert Boyd. “The Big Man Mechanism: how prestige fosters cooperation and creates prosocial leaders.” Philosophical Transactions of the Royal Society B 370, no. 1683 (2015). Publisher's Version PDF
Henrich, J.Culture and social behavior.” Current Opinion in Behavioral Sciences 3 (2015): 84-89. PDF
Fessler, D. M. T., H. C. Barret, M. Kanovsky, S. Stich, C. Holbrook, J. Henrich, A. H. Bolyanatz, et al.Moral parochialism and contextual contingency across seven societies.” Proceedings of the Royal Society B 282 (2015): 20150907. Online Access PDF
McKerracher, L., M. Collard, and J. Henrich. “The expression and adaptive significance of pregnancy-related nausea, vomiting, and aversions on Yasawa Island, Fiji.” Evolution and Human Behavior 36, no. 2 (2015): 95-102. PDF
Moya, C., R. Boyd, and J. Henrich. “Reasoning about cultural and genetic transmission: Developmental and cross-cultural evidence from Peru, Fiji, and the US on how people make inferences about trait and identity transmission.” Topics in Cognitive Science 7, no. 4 (2015): 595-610. PDF
Salali, Gul Deniz, Myriam Juda, and Joseph Henrich. “Transmission and development of costly punishment in children.” Evolution and Human Behavior 36 (2015): 86-94.Abstract

Evolutionary theorists argue that cultural evolution has harnessed various aspects of our evolved psychology to create a variety of different mechanisms for sustaining social norms, including those related to large-scale cooperation. One of these mechanisms, costly punishment, has emerged in experiments as an effective means to sustain cooperation in some societies. If this view is correct, individuals' willingness to engage in the costly punishment of norm violators should be culturally transmittable, and applicable to both prosocial and anti-social behaviors (to any social norm). Since much existing work shows that norm-based prosocial behavior in experiments develops substantially during early and middle childhood, we tested 245 3- to 8-year olds in a simplified third party punishment game to investigate whether children would imitate a model's decision to punish, at a personal cost, both unequal and equal offers. Our study showed that children, regardless of their age, imitate the costly punishment of both equal and unequal offers, and the rates of imitation increase (not decrease) with age. However, only older children imitate not-punishing for both equal and unequal offers. These findings highlight the potential role of cultural transmission in the stabilization or de-stabilization of costly punishment in a population.

Broesch, J., J. Henrich, and H. C. Barrett. “Adaptive Content Biases in Learning about Animals Across the Lifecourse.” Human Nature 25, no. 2 (2014): 181-199. PDF
Hruschka, D., C. Efferson, T. Jiang, A. Falletta-Cowden, S. Sigurdsson, R. McNamara, M. Sands, S. Munira, E. Slingerland, and J. Henrich. “Impartial Institutions, Pathogen Stress and the Expanding Social Network.” Human Nature 25, no. 4 (2014): 567-579.Abstract

Anthropologists have documented substantial cross-society variation in people's willingness to treat strangers with impartial, universal norms versus favoring members of their local community. Researchers have proposed several adaptive accounts for these differences. One variant of the pathogen stress hypothesis predicts that people will be more likely to favor local in-group members when they are under greater infectious disease threat. The material security hypothesis instead proposes that institutions that permit people to meet their basic needs through impartial interactions with strangers reinforce a tendency toward impartiality, whereas people lacking such institutions must rely on local community members to meet their basic needs. Some studies have examined these hypotheses using self-reported preferences, but not with behavioral measures. We conducted behavioral experiments in eight diverse societies that measure individuals' willingness to favor in-group members by ignoring an impartial rule. Consistent with the material security hypothesis, members of societies enjoying better-quality government services and food security show a stronger preference for following an impartial rule over investing in their local in-group. Our data show no support for the pathogen stress hypothesis as applied to favoring in-groups and instead suggest that favoring in-group members more closely reflects a general adaptive fit with social institutions that have arisen in each society.

Henrich, J.Rice, Psychology and Innovation.” Science 344, no. 6184 (2014): 593. PDF
Muthukrishna, Michael, Ben W Shulman, Vlad Vasilescu, and Joseph Henrich. “Sociality influences cultural complexity.” Proceedings of the Royal Society B: Biological Sciences 281, no. 1774 (2014): 20132511. PDF
Chudek, M., and J. Henrich. “Tackling Group-Level Traits by Starting at the Start.” Behavioral and Brain Sciences 37, no. 3 (2014): 256-7. PDF
Bauer, M., A. Cassar, J. Chytilova, and J. Henrich. “War's Enduring Effects on the Development of Egalitarian Motivations and In-Group Biases.” Psychological Science 25, no. 1 (2014): 47-57.Abstract

In suggesting that new nations often coalesce in the decades following war, historians have posed an important psychological question: Does the experience of war generate an enduring elevation in people's egalitarian motivations toward their in-group? We administered social-choice tasks to more than 1,000 children and adults differentially affected by wars in the Republic of Georgia and Sierra Leone. We found that greater exposure to war created a lasting increase in people's egalitarian motivations toward their in-group, but not their out-groups, during a developmental window starting in middle childhood (around 7 years of age) and ending in early adulthood (around 20 years of age). Outside this window, war had no measurable impact on social motivations in young children and had only muted effects on the motivations of older adults. These war effects are broadly consistent with predictions from evolutionary approaches that emphasize the importance of group cooperation in defending against external threats, though they also highlight key areas in need of greater theoretical development.



Cheng, J. T., J. L. Tracy, T. Foulsham, A. Kingstone, and J. Henrich. “Two Ways to the Top: Evidence That Dominance and Prestige Are Distinct Yet Viable Avenues to Social Rank and Influence.” Journal of Personality and Social Psychology 104, no. 1 (2013): 103-125. PDF
Silk, J. B., S. F. Brosnan, J. Henrich, S. P. Lambeth, and S. Shapiro. “Chimpanzees share food for many reasons: the role of kinship, reciprocity, social bonds and harassment on food transfers.” Animal Behaviour 85, no. 5 (2013): 941-947. PDF
Tracy, J. L., A. F. Shariff, W. Zhao, and J. Henrich. “Cross-cultural evidence that the pride expression is a universal automatic status signal.” Journal of Experimental Psychology-General 142, no. 1 (2013): 163-180. PDF Supplement
House, B., J. Henrich, B. Sarnecka, and J. B. Silk. “The development of contingent reciprocity in children.” Evolution and Human Behavior 34, no. 2 (2013): 86-93.Abstract

Cooperation between nonrelatives is common in humans. Reciprocal altruism is a plausible evolutionary mechanism for cooperation within unrelated pairs, as selection may favor individuals who selectively cooperate with those who have cooperated with them in the past. Reciprocity is often observed in humans, but there is only limited evidence of reciprocal altruism in other primate species, raising questions about the origins of human reciprocity. Here, we explore how reciprocity develops in a sample of American children ranging from 3 to 7.5 years of age, and also compare children's behavior to that of chimpanzees in prior studies to gain insight into the phylogeny of human reciprocity. Children show a marked tendency to respond contingently to both prosocial and selfish acts, patterns that have not been seen among chimpanzees in prior studies. Our results show that reciprocity increases markedly with age in this population of children, and by about 5.5 years of age children consistently match the previous behavior of their partners. (C) 2013 Published by Elsevier Inc.

Barrett, H. C., T. Broesch, R. M. Scott, Z. J. He, R. Baillargeon, D. Wu, M. Bolz, et al.Early false-belief understanding in traditional non-Western societies.” Proceedings of the Royal Society B-Biological Sciences 280, no. 1755 (2013): 20122654.Abstract

The psychological capacity to recognize that others may hold and act on false beliefs has been proposed to reflect an evolved, species-typical adaptation for social reasoning in humans; however, controversy surrounds the developmental timing and universality of this trait. Cross-cultural studies using elicited-response tasks indicate that the age at which children begin to understand false beliefs ranges from 4 to 7 years across societies, whereas studies using spontaneous-response tasks with Western children indicate that false-belief understanding emerges much earlier, consistent with the hypothesis that false-belief understanding is a psychological adaptation that is universally present in early childhood. To evaluate this hypothesis, we used three spontaneous-response tasks that have revealed early false-belief understanding in the West to test young children in three traditional, non-Western societies: Salar (China), Shuar/Colono (Ecuador) and Yasawan (Fiji). Results were comparable with those from the West, supporting the hypothesis that false-belief understanding reflects an adaptation that is universally present early in development.