The effects of social exclusion on distributive fairness judgements and cooperative behaviour.

In this article, we investigate how being socially excluded (vs. included) affects people's distributive fairness judgements and their willingness to cooperate with others in subsequent interactions. For this purpose, we conducted three experiments in which we assessed individual differences in having experienced being socially excluded (Experiment 1, N = 164), and manipulated social exclusion (Experiment 2, N = 120; Experiment 3, N = 492).

Discriminatory punishment undermines the enforcement of group cooperation.

Peer punishment can help groups to establish collectively beneficial public goods. However, when humans condition punishment on other factors than poor contribution, punishment can become ineffective and group cooperation deteriorates. Here we show that this happens in pluriform groups where members have different socio-demographic characteristics.

The evolution of universal cooperation.

Humans work together in groups to tackle shared problems and contribute to local club goods that benefit other group members. Whereas benefits from club goods remain group bound, groups are often nested in overarching collectives that face shared problems like pandemics or climate change. Such challenges require individuals to cooperate across group boundaries, raising the question how cooperation can transcend beyond confined groups.