Prosocial Emotion, Adolescence, and Warfare (original) (raw)
Related papers
American Journal of Human Biology, 2020
Objectives: Candidate gene methylation studies of NR3C1 have identified associations with psychosocial adversity, including war trauma. This pilot study (sample sizes from 22 to 45 for primary analyses) examined NR3C1 methylation in a group of Kenyan pastoralist young men in relation to culturally relevant traumatic experiences, including participation in coalitional lethal gun violence. Methods: Adolescent and young adult Samburu men ("warriors") were recruited for participation. DNA was obtained from whole saliva and methylation analyses performed using mass spectrometry. We performed a data reduction of variables from a standardized instrument of lifetime stress using a factor analysis and we assessed the association between the extracted factors with culturally relevant and cross-culturally comparative experiences. Results: Cumulative lifetime trauma exposure and forms of violence to which warriors are particularly susceptible were associated with DNA methylation changes in the NR3C1 1 F promoter region but not in the NR3C1 1 D promoter region. However, sensitivity analyses revealed significant associations between individual CpG sites in both regions and cumulative stress exposures, war exposure timing, and war fatalities. Conclusions: This study supports the importance of NR3C1 methylation changes in response to challenging life circumstances, including in a global south cultural context that contrasts in notable ways from global north contexts and from the starkly tragic examples of the Rwandan genocide and warassociated rape explored in recent studies. Timing of traumatic exposure and culturally salient means to measure enduring symptoms of trauma remain important considerations for DNA methylation studies.
Do genes influence exposure to trauma? A twin study of combat
American Journal of Medical Genetics, 1993
Data from 4,029 male-male twin pairs who served in the United States military during the Vietnam era (1965–1975) were used to examine genetic and non-genetic factors that influence wartime exposure to traumatic events. Specific events examined were volunteering for service in Vietnam, actual service in Southeast Asia, a composite index of 18 combat experiences, and information from military records about being awarded combat decorations. Correlations within monozygotic (MZ) and dizygotic (DZ) twin pairs for volunteering for service in Vietnam were 0.40 and 0.22, respectively. For actually serving in Southeast Asia, the MZ correlation was 0.41 and the DZ correlation was 0.24. Analysis of twin pairs in which both siblings served in Southeast Asia (n = 820) demonstrated a correlation for self-reported combat experiences within MZ and DZ pairs of 0.53 and 0.30, respectively. Heritability estimates ranged from 35 to 47%. The family environment did not have a significant effect on any of the variables. Analyses of data from military records regarding being awarded a combat decoration provided very similar results to those found for self-reported combat experiences. © 1993 Wiley-Liss, Inc.
Ancestral war and the evolutionary origins of ‘heroism.’ (2007, with Smirnov, Kennettt, Orbell)
"Smirnov, O., Arrow, H., Kennett, D., & Orbell, J. (2007). Ancestral war and the evolutionary origins of ‘heroism.’ Journal of Politics, 69 (4), 927-940. Primatological and archeological evidence along with anthropological accounts of hunter-gatherer societies indicate that lethal between-group violence may have been sufficiently frequent during our ancestral past to have shaped our evolved behavioral repertoire. Two simulations explore the possibility that heroism (risking one’s life fighting for the group) evolved as a specialized form of altruism in response to war.We show that war selects strongly for heroism but only weakly for a domain-general altruistic propensity that promotes both heroism and other privately costly, group-benefiting behaviors. A complementary analytical model shows that domain-specific heroism should evolve more readily when groups are small and mortality in defeated groups is high, features that are plausibly characteristic of our collective ancestral past.
Aggression and polymorphisms in AR, DAT1, DRD2, and COMT genes in Datoga pastoralists of Tanzania
The aim of this study was to analyse the relationships between polymorphisms in four candidate genes (AR, DAT1, DRD2, and COMT) and aggression in men from a traditional society of East African pastoralists, the Datoga. Buss and Perry's Aggression Questionnaire was used to measure aggression. The number of CAG repeats in the AR gene was negatively correlated with physical aggression, anger, and hostility. Among the genes of the dopaminergic system, a significant single-gene effect was detected only for DRD2 with regard to anger. At the level of a two-gene model, a significant effect for DRD2 and a tendency for DAT1 were observed for the DAT1-DRD2 gene pair regarding hostility, and two tendencies were observed for the interaction effect of the DAT1-COMT pair regarding anger and hostility. These data suggest a probable link between physical aggression and direct fitness caused by strong sexual selection in Datoga men.
MAOA and Aggression: A Gene-Environment Interaction in Two Populations
Journal of Conflict Resolution, 2013
Political scientists tend to focus on environmental triggers as the primary precipitating cause for political violence. However, little has been done to explain why certain individuals faced with certain pressures resort to violence, while others confronting the same situation seek out diplomatic and peaceful resolutions to conflict.
Killing, Mercy, and Empathic Emotions: The Emotional Lives of East African Warriors
Human Conflict from Neanderthals to the Samburu: Structure and Agency in Webs of Violence, 2020
In 2016, a minimum of 145,109 persons were killed directly in armed conflicts worldwide (Wikipedia Armed Conflicts page 2017). 1 Armed conflict deaths are not normatively construed as murders even if each "side" condemns the other. Rather, these deaths are accomplished by "normal" individuals culturally conditioned and often trained to kill. The question of whether violence is an aspect of human nature, perhaps conferring an evolutionary advantage, is an enduringly controversial one. Although we do not take a position on either side of the debate in this paper, our concerns are relevant to it. For background, we discuss the conditions under which "normal" humans will inflict harm on other humans in the context of social pressure. This research complements and amplifies the "web of violence" approach insofar as it attempts to overcome the "tendency to see violence as the consequence of aberrant behavior committed by deviant individuals at the margins of society" (Turpin and Kurtz 1997:207), showing instead the way violence and human conflict play a central role in society. Our overarching concern is with the role of empathy
Evolutionary Psychology and Warfare
SAGE Handbook of Evolutionary Psychology, 2020
The scientific study of the evolution of human coalitional aggression has exploded over the last three decades. In four parts, I explore and integrate many of the useful frameworks that have emerged to describe and explain the human practice of intergroup violence. First, we have a clearer understanding of the general conditions required for the evolution of adaptations for coalitional aggression. Second, given an understanding of these conditions, we can more usefully examine the historic and prehistoric record for evidence of the existence of these conditions. Third, I explore and integrate current lab and field evidence for psychological adaptations for coalitional aggression. This section reveals a core dynamic underlying all forms of coalitional aggression: the form of intergroup engagement is functionally linked with the emergent patterns of intragroup dynamics. In other words, how we fight “abroad” determines how we cooperate “at home,” and vice versa. I examine five areas of inquiry that suggest special design for coalitional aggression. These are: the collective action problem of coordinated violence; parochial altruism; attacker-defender asymmetries; leader-follower dynamics; sex differences in the costs and benefits of violence. Fourth, and to conclude, I offer speculation on the historical emergence of modern human warfare. I do not use “coalitional aggression” and “warfare” interchangeably; rather, evolved psychological adaptations for small-scale coalitional aggression are what make the historical emergence of large-scale human warfare possible.
Proceedings of the National Academy of Sciences of the United States of America, 2016
Adverse social conditions in early life have been linked to increased expression of proinflammatory genes and reduced expression of antiviral genes in circulating immune cells-the conserved transcriptional response to adversity (CTRA). However, it remains unclear whether such effects are specific to the Western, educated, industrialized, rich, and democratic (WEIRD) cultural environments in which previous research has been conducted. To assess the roles of early adversity and individual psychological resilience in immune system gene regulation within a non-WEIRD population, we evaluated CTRA gene-expression profiles in 254 former child soldiers and matched noncombatant civilians 5 y after the People's War in Nepal. CTRA gene expression was up-regulated in former child soldiers. These effects were linked to the degree of experienced trauma and associated distress-that is, posttraumatic stress disorder (PTSD) severity-more than to child soldier status per se. Self-perceived psycho...
Warfare and Social Preferences In Children
2010
Since Darwin, warfare and inter-group hostilities have been hypothesized as catalysts in explanations for the evolutionary puzzle of human pro-sociality. Lethal conflicts would foster the development of social norms that suppress competition within groups, strengthen preference for ...