The social function of the feeling and expression of guilt

Humans are uniquely cooperative and form crucial short-and long-term social bonds between individuals that ultimately shape human societies. The need for such intense cooperation may have provided a particularly powerful selection pressure on the emotional and communicative behaviours regulating cooperative processes, such as guilt. Guilt is a social, other-oriented moral emotion that promotes relationship repair and pro-sociality. For example, people can be more lenient towards wrongdoers who display guilt than towards those who do not. Here we examined the social consequences of guilt in a novel experimental setting with pairs of friends differing in relationship quality. Pairs of participants took part in a cooperative game with a mutual goal. We then induced guilt in one of the participants and informed the other participant of their partner’s wrongdoing. We examined the outcome using a dictator game to see how they split a joint reward. We found that guilty people were motivated to repair wrongdoing regardless of friendship. Observing guilt in others led to a punishment effect and a victim of wrongdoing punished close friends who appeared guilty more so than acquaintances. We suggest, therefore, that guilt has a stronger function between close friends as the costs of relationship breakdown are greater. Relationship context, therefore, is crucial to the functional relevance of moral emotions

Desert ants (Melophorus bagoti) navigating with robustness to distortions of the natural panorama

Many insects are known to use the terrestrial visual panorama for navigation. Research suggests that large-scale panoramic properties are often used for orientation rather than individual objects, usually called landmarks. We degraded the natural panorama encountered by Australian red honey ants, Melophorus bagoti, to test how robust their orientation based on the terrestrial panorama is. Foraging ants were lured to a feeder at a constant location. Trained ants were allowed to run home individually with food, but were captured just before they entered their nest. The tested ant was brought back to the location of the feeder, now covered, and allowed to run home again under different distortions of the natural panorama. In one experiment, a large tract of the view on one side of the feeder was obstructed by a tall plastic sheet. In a second experiment, the visual heights of terrestrial objects were altered by raising or lowering the ant by 80 cm. Under both kinds of distortions, the ants continued to be well oriented in the homeward direction. Navigation based on the natural terrestrial panorama proved robust to large distortions.13 page(s