Many accounts of ethnic phenomena imply that processes such as stereotyping, essentialism, ethnocentrism, and intergroup hostility stem from a unitary adaptation for reasoning about groups. This is partly justified by the phenomena’s co-occurrence in correlational studies. Here we argue that these behaviors are better modeled as functionally independent adaptations that arose in response to different selection pressures throughout human evolution. As such, different mechanisms may be triggered by different group boundaries within a single society. We illustrate this functionalist framework using (...) ethnographic work from the Quechua-Aymara language boundary in the Peruvian Altiplano. We show that different group boundaries motivate different ethnic phenomena. For example, people have strong stereotypes about socioeconomic categories, which are not cooperative units, whereas they hold fewer stereotypes about communities, which are the primary focus of cooperative activity. We also show that, despite the cross-cultural importance of ethnolinguistic boundaries, the Quechua-Aymara linguistic distinction does not strongly motivate any of these intergroup processes. (shrink)

Using samples from three diverse populations, we test evolutionary hypotheses regarding how people reason about the inheritance of various traits. First, we provide a framework for differentiat-ing the outputs of mechanisms that evolved for reasoning about variation within and between biological taxa and culturally evolved ethnic categories from a broader set of beliefs and categories that are the outputs of structured learning mechanisms. Second, we describe the results of a modified “switched-at-birth” vignette study that we administered among children and adults (...) in Puno, Yasawa, and adults in the United States. This protocol permits us to study perceptions of prenatal and social transmission pathways for various traits and to differentiate the latter into vertical versus horizontal cultural influence. These lines of evidence suggest that people use all three mechanisms to reason about the distribution of traits in the population. Participants at all three sites develop expectations that morphological traits are under prenatal influence, and that belief traits are more culturally influenced. On the other hand, each population holds culturally specific beliefs about the degree of social influence on non-morphological traits and about the degree of vertical transmission—with only participants in the United States expecting parents to have much social influence over their children. We reinterpret people's differentiation of trait transmission pathways in light of humans' evolutionary history as a cultural species. (shrink)

Perhaps because groupishness comes so easily to humans, clear operational definitions of the phenomena and justifications for the claim that it is deep‐seated are lacking in much of the literature. Furthermore, the assertion of human groupishness glosses over several important questions including which behaviors, which social boundaries, and which evolutionary processes make us groupish. In this paper I use an evolutionary lens, and cross‐species and cross‐cultural comparative examples to clarify the bases on which such a claim of particular human groupishness (...) can be made. Specifically, if humans are particularly groupish, it is because we produce culturally‐structured social landscapes. This means the cognitive science of groupishness must incorporate the social science of the cultural evolution of group boundaries. (shrink)

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 collected by a team of anthropologists and psychologists conducting long-term research in each society. The six datasets include video observations of children among the Yasawas, Tanna, Tsimane, Huatasani, and Aka. Each dataset consists of a series of videos of children ranging in age (...) from 2 months to 12 years in their everyday contexts. We coded 998 videos and identified with whom children had opportunities to interact as well as the number of individuals and the proportion of observed time that children spent with these individuals. We also examined the proportion of time children received direct visual gaze. Our results indicate that children less than 5 years old spend the majority of their observed time in the presence of one female adult. This is the case across the five societies. In the three societies from which we have older children, we find a clear shift around 5 years of age, with children spending the majority of their time with other children. We also coded the presence or absence of a primary caregiver and found that caregivers remained within 2 ft of target children until 7 years of age. When they were in the company of a primary caregiver, children older than seven spent the majority of their time more than 2 ft from the caregiver. We found a consistent trend across societies with decreasing focal attention on the child with increasing child age. These findings show remarkable consistency across these societies in children’s interaction opportunities and that a developmental approach is needed to fully understand human development because the social context is dynamic across the lifespan. These data can serve as a springboard for future research examining social development in everyday contexts. (shrink)

Several researchers have proposed that humans are predisposed to treat ethnic identities as stable and inherent. However, the ethnographic, historical, and genetic records attest to the ubiquity of inter-ethnic migrations across human history. These two claims seem to be at odds. In this article we compare three evolutionary accounts of how people reason about identity stability, and the effect that the cultural evolution of ethnic group boundaries may have on these beliefs. We test our hypotheses among Himba pastoralists in Namibia, (...) whose recent fission from the neighboring Herero makes them ideal for studying the effect of cultural distance on folk beliefs about identity stability. In a vignette experiment, we asked participants whether an individual born in one group who moved to another group would retain their original group membership and cultural characteristics or acquire those of the new group. Across vignette conditions we examine the importance of the direction of migration, parental social influence, and age at migration on perceptions of identity stability. We also compare participant responses to two out-groups, the Herero, and the more distantly related Damara. We find that participants seldom thought of identity as stable or fixed at birth. Furthermore, we show that cultural distance and endogamous preferences are independent of beliefs of identity stability. Himba believed the Damara character was more likely to change identity and cultural traits than was the Herero character, despite their greater cultural distance from the former group, and despite the fact that all participants expressed more anti-Damara than anti-Herero sentiment. (shrink)