Validating the dual evolutionary foundations of political values in a US sample.

Psychological research repeatedly identifies two dimensions of political values. Recent work argues that these dimensions reflect the dual evolutionary foundations of human social and political life: a trade-off between cooperation and competition that generates differences in values about social inequality, and a trade-off in managing group coordination that generates differences in values about social control. Existing scales used to measure political values, however, were created prior to this framework. Here, we introduce the Dual Foundations Scale, designed to capture values about the two trade-offs. We validate the scale across two studies, showing it accurately and reliably measures both dimensions. Our results support key predictions of the dual foundations framework and pave the way for future work on the foundations of political ideology.

Cooperative and conformist behavioural preferences predict the dual dimensions of political ideology.

Decades of research suggest that our political differences are best captured by two dimensions of political ideology. The dual evolutionary framework of political ideology predicts that these dimensions should be related to variation in social preferences for cooperation and group conformity. Here, we combine data from a New Zealand survey and a suite of incentivised behavioural tasks (n = 991) to test whether cooperative and conformist preferences covary with a pair of widely used measures of the two dimensions of political ideology-Social Dominance Orientation (SDO) and Right Wing Authoritarianism (RWA)-and related policy views. As predicted, we find that cooperative behaviour is negatively related to SDO and economically conservative policy views, while conformist behaviour in the form of social information use is positively related to RWA and socially conservative policy views. However, we did not find the predicted relationships between punitive and rule following behaviours and RWA or socially conservative views, raising questions about the interpretation of punishment and rule following tasks and the nature of authoritarian conformist preferences. These findings reveal how cooperative and conformist preferences that evolved to help us navigate social challenges in our ancestral past continue to track our political differences even today.

Cooperative phenotype predicts climate change belief and pro-environmental behaviour.

Understanding the psychological causes of variation in climate change belief and pro-environmental behaviour remains an urgent challenge for the social sciences. The "cooperative phenotype" is a stable psychological preference for cooperating in social dilemmas that involve a tension between individual and collective interest. Since climate change poses a social dilemma on a global scale, this issue may evoke similar psychological processes as smaller social dilemmas. Here, we investigate the relationships between the cooperative phenotype and climate change belief and behaviour with a representative sample of New Zealanders (N = 897). By linking behaviour in a suite of economic games to self-reported climate attitudes, we show robust positive associations between the cooperative phenotype and both climate change belief and pro-environmental behaviour. Furthermore, our structural equation models support a motivated reasoning account in which the relationship between the cooperative phenotype and pro-environmental behaviour is mediated by climate change belief. These findings suggest that common psychological mechanisms underlie cooperation in both micro-scale social dilemmas and larger-scale social dilemmas like climate change.

The dual evolutionary foundations of political ideology.

Research over the last fifty years has suggested that political attitudes and values around the globe are shaped by two ideological dimensions, often referred to as economic and social conservatism. However, it remains unclear why this ideological structure exists. Here we highlight the striking concordance between these dual dimensions of ideology and independent convergent evidence for two key shifts in the evolution of human group living. First, humans began to cooperate more and across wider interdependent networks. Second, humans became more group-minded, conforming to social norms in culturally marked groups and punishing norm-violators. We propose that fitness trade-offs and behavioural plasticity have maintained functional variation in willingness to cooperate and conform within modern human groups, naturally giving rise to the two dimensions of political ideology. Supported by evidence from across the behavioural sciences, this evolutionary framework provides insight into the biological and cultural basis of political ideology.

On the long-run efficacy of punishments and recommendations in a laboratory public goods game.

We use decision-making experiments with human participants to study cooperation in a laboratory public goods game. Such games pose a conflict between cooperating, which is socially optimal and free-riding, which promotes individual self-interest. Prior research emphasizes the need for de-centralized peer-to-peer punishments as an evolutionarily stable response to the problem of free-riding, especially where interactions occur over long horizons. We show that a simple exhortative message appealing to participants' goodwill can achieve high rates of cooperation in social dilemmas played over many rounds, even in the absence of punishments for free-riding.