SignificanceBiologists and social scientists have long tried to understand why some societies have more fluid and open interpersonal relationships—differences in relational mobility—and how those differences influence individual behaviors. We measure relational mobility in 39 societies and find that relationships are more stable and hard to form in east Asia, North Africa, and the Middle East, while they are more fluid in the West and Latin America. Results show that relationally mobile cultures tend to have higher interpersonal trust and intimacy. Exploring potential causes, we find greater environmental threats (like disease and warfare) and sedentary farming are associated with lower relational mobility. Our society-level index of relational mobility for 39 societies is a resource for future studies.

Social psychological research has overlooked collective action in repressive contexts, where activists face substantial personal risks. This paper examines the social psychological processes motivating activists to engage in collective action in risky contexts. We investigate the idea that perceived risks due to government sanctions can galvanize action through fuelling anger, shaping efficacy beliefs, and increasing identification with the movement. We also argue that anger, efficacy, and identification motivate action intentions directly and indirectly through reducing the personal importance activists attach to these risks. We tested our hypotheses within a sample of Egyptian activists (N = 146) from two protest movements who protested against Morsi's government and the military interventions, respectively, during the 2013 anticoup uprising. In line with our hypotheses, the perceived likelihood of risks was positively associated with anger and identity consolidation efficacy and positively predicted action intentions indirectly through these variables. Risk was also associated with increased political efficacy, but only among antimilitary protesters. Anger and political efficacy predicted action intentions directly and indirectly through reduced risk importance. Results also highlighted differential significance of emotional and instrumental motives for the two protest movements. We discuss directions for future research on the motivators of collective action in repressive contexts.

the small group meeting on "Trajectories of Radicalisation and De-Radicalisation" at the Queensland University in Australia in 2018. We like to thank Oleskii Shestakovskyi for his valuable help in adapting the questionnaire to the Ukrainian context and translating it to Ukrainian.

Collective nostalgia refers to longing for the way society used to be. We tested whether collective nostalgia is associated with ingroup-favoring collective action and whether this association is mediated by outgroup-directed anger and outgroup-directed contempt. We conducted an online study of Hong Kong residents (N = 111) during a large-scale democratic social movement, the Umbrella Movement, that took place in Hong Kong in 2014 in response to proposed electoral reforms by the Chinese government in Mainland China. Reported collective nostalgia for Hong Kong’s past was high in our sample and collective nostalgia predicted stronger involvement in ingroup-favoring collective action, and it did so indirectly via higher intensity of outgroup-directed anger (but not through outgroup-directed contempt). We argue that collective nostalgia has implications for strengthening ingroup-serving collective action, and we highlight the importance of arousal of group-based emotions in this process.

No abstract