Are capuchin monkeys (Cebus apella) inequity averse

摘要: It has been reported that capuchin monkeys reject a less preferred food (LPF) when they see partner receive more (PF) for performing the same task. This behaviour was taken as evidence of ‘inequity aversion’, but an alternative hypothesis is capuchins LPF because mere presence PF. We tested this in paradigm, which consisted presenting two different foods (one PF and one LPF) on tray allowing to take only LPF. Refusals initiate trial refusals eat were higher hidden (hiding condition) accumulated sight out reach subject (accumulation compared pieces placed (control condition). Interestingly, behaved control condition its given ate (partner argue capuchins' due frustration seeing not obtaining PF, eating increases acceptance.