Details

Autor(en) / Beteiligte

• Engelmann, Jan M
• Clift, Jeremy B
• Herrmann, Esther
• Tomasello, Michael

Titel

Social disappointment explains chimpanzees' behaviour in the inequity aversion task

Ist Teil von

• Proceedings of the Royal Society. B, Biological sciences, 2017-08, Vol.284 (1861)

Ort / Verlag

England

Erscheinungsjahr

2017

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Chimpanzees' refusal of less-preferred food when an experimenter has previously provided preferred food to a conspecific has been taken as evidence for a sense of fairness. Here, we present a novel hypothesis-the social disappointment hypothesis-according to which food refusals express chimpanzees' disappointment in the human experimenter for not rewarding them as well as they could have. We tested this hypothesis using a two-by-two design in which food was either distributed by an experimenter or a machine and with a partner present or absent. We found that chimpanzees were more likely to reject food when it was distributed by an experimenter rather than by a machine and that they were not more likely to do so when a partner was present. These results suggest that chimpanzees' refusal of less-preferred food stems from social disappointment in the experimenter and not from a sense of fairness.