Culture does account for variation in game behavior

Abstract

Lamba and Mace's critique (1) of our research (2-4) is based on incorrect claims about our experiments and several misunderstandings of the theory underpinning our efforts. Their findings are consistent with our previous work and lead to no unique conclusions.Lambda and Mace (1) incorrectly claimed that we "mostly" sampled from single communities within sites, and that we ignored "ecological" and "demographic" variables. In fact, much of our work focused on studying the variation among communities within sites. In phase I (2), 8 of 15 sites involved multiple communities, and in phase II (3, 4), 11 of our 16 sites sampled from multiple communities. Several sites included 5 communities*, and 1 site included 9 communities (5).During both phases, we conducted analyses like Lamba and Mace's (1) within each of our sites (2-4). Except for community size, which emerged as a focal predictor (4), we studied versions of all the key variables (age, network centrality, and siblings) of Lamba and Mace (1) in some populations. Occasionally, these were significant, but none had consistent effects across populations, games, or in retests years later. Lamba and Mace (1) also failed to find any predictors that were consistent across their experiments, despite trying dozens of variables. Moreover, their predictors are neither theoretically well-grounded nor particularly ecological. Nonetheless, Lamba and Mace (1) concluded that "ecology drives variation in cooperation."Our analyses show that the key claim of Lamba and Mace (1), that the fraction of variation they observed for monetary games (4%) among communities is comparable to the fraction we observe among our sites (12% for ultimatum game offers in phase I) is not correct, even allowing for their assumption that 12 ≈ 4. (1) is consistent with our data, but their data tell us nothing about the variation across sites (contrary to their claim).Our theoretical framework is also not made clear, because Lamba and Mace (1) claimed that our approach holds that only norms matter, and that norms cannot evolve in response to ecological variation. They further imply that if demographic or ecological variation is important, norms cannot be. Our research is based on the idea that people can acquire context-specific expectations (e.g., "one wife per man") and internalized motivations (e.g., "extramarital sex is wrong") as a consequence of cultural learning. These expectations and motivations then influence their decision making along with other factors, including evolved motivations linked to self-interest and genetic relatedness (2). Thus, as conditions vary, so too does behavior, even if people share such norms.*

Harsh childhood environmental characteristics predict exploitation and retaliation in humans

“…These within-population individual differences are, in principle, amenable to individual-level explanations, as the architects of the cultural group selection approaches to cooperation readily concede [5,43]. Consistent with Daly & Wilson's [26] characterization of the young male syndrome, the associations that emerged here suggest (though, owing to the correlational nature of the data, do not demonstrate definitively) that men's (but not women's) childhood experiences with crime, violence, neglect and conflict-both within the family and the neighbourhood-predispose them towards stronger propensities for impulsive defection against cooperatively disposed players, as well as to greater retaliation when their interaction partners suddenly become uncooperative.…”

Population structure and cultural geography of a folktale in Europe

“…Rzeszutek et al [38] examined cross-cultural variation in song characteristics across 16 Formosan-speaking ethnolinguistic groups and found an overall F ST of 0.02, indicating that approximately 2 per cent of variation was between populations. In addition, debates in experimental economics have begun to focus on within-versus between-population variation in strategies employed in economic games [39][40][41].…”

Reply to Henrich et al.: Behavioral variation needs to be quantified at multiple levels

“…Henrich et al (1)(2)(3)(4) and other scholars [e.g., Herrmann et al (5)] have used innovative quantitative methods to demonstrate substantial behavioral variation across human populations. Building on this literature, our work (6) demonstrates the need to quantify the relative behavioral variation at different levels (e.g., ethnolinguistic groups, villages, individuals) and identify the relative importance of different mechanisms that drive and maintain this variation.…”