To benefit from information provided by others, people must be somewhat credulous. However, credulity entails risks. The optimal level of credulity depends on the relative costs of believing misinformation versus failing to attend to accurate information. When information concerns hazards, erroneous incredulity is often more costly than erroneous credulity, as disregarding accurate warnings is more harmful than adopting unnecessary precautions. Because no equivalent asymmetry characterizes information concerning benefits, people should generally be more credulous of hazard information than of benefit information. This adaptive negatively-biased credulity is linked to negativity bias in general, and is more prominent among those who believe the world to be dangerous. Because both threat sensitivity and dangerous-world beliefs differ between conservatives and liberals, we predicted that conservatism would positively correlate with negatively-biased credulity. Two online studies of Americans support this prediction, potentially illuminating the impact of politicians’ alarmist claims on different portions of the electorate.

This file contains the complete datasets described in http://dx.doi.org/10.1371/journal.pone.0095167

This archive contains the complete datasets described in Fessler et al.'s "Political Orientation Predicts Credulity Regarding Putative Hazards", along with the analytic variables and R code employed, each as separate files.

Objectives

This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.

Methods

Maximal oxygen uptake (VO2 max) was estimated using a step test heart rate method for 701 participants. We compared these estimates to the Canadian Health Measures Survey and previous studies in industrialized and subsistence populations. We evaluated whether health indicators and proxies for market integration were associated with VO2 max levels and rate of decline for the Tsimane.

Results

The Tsimane have significantly higher levels of VO2 max and slower rates of decline than Canadians; initial evidence suggests differences in VO2 max levels between other subsistence and industrialized populations. Low hemoglobin predicts low VO2 max for Tsimane women while helminth infection predicts high VO2 max for Tsimane men, though results might be specific to the VO2 max scaling parameter used. No variables tested interact with age to moderate decline.

Conclusions

The Tsimane demonstrate higher levels of cardiovascular fitness than industrialized populations, but levels similar to other subsistence populations. The high VO2 max of Tsimane is consistent with their high physical activity and few indicators of cardiovascular disease, measured in previous studies.

The intensifying pace of research based on cross-cultural studies in the social sciences necessitates a discussion of the unique challenges of multi-sited research. Given an increasing demand for social scientists to expand their data collection beyond WEIRD (Western, educated, industrialized, rich and democratic) populations, there is an urgent need for transdisciplinary conversations on the logistical, scientific and ethical considerations inherent to this type of scholarship. As a group of social scientists engaged in cross-cultural research in psychology and anthropology, we hope to guide prospective cross-cultural researchers through some of the complex scientific and ethical challenges involved in such work: (a) study site selection, (b) community involvement and (c) culturally appropriate research methods. We aim to shed light on some of the difficult ethical quandaries of this type of research. Our recommendation emphasizes a community-centred approach, in which the desires of the community regarding research approach and methodology, community involvement, results communication and distribution, and data sharing are held in the highest regard by the researchers. We argue that such considerations are central to scientific rigour and the foundation of the study of human behaviour.