Domestication Lab, Konrad Lorenz Institute of Ethology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine, Vienna, Dörfles 48, 2115, Ernstbrunn, Austria.
Institute of Animal Welfare Science, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria.
Sci Rep. 2023 Jul 26;13(1):12066. doi: 10.1038/s41598-023-38836-w.
Dogs have repeatedly been shown to give their paw to an experimenter more times for no reward when a rewarded conspecific partner is absent than when a rewarded conspecific is present, thereby showing inequity aversion. However, rather than being inequity averse, dogs might give their paw more when a partner is absent due to the experimenter's procedure in which they move food in front of the subject to mimic feeding a partner. This action could increase subjects' perception of reward attainability. We tested this hypothesis by introducing an improved type of control condition in which subjects were unrewarded for giving the paw in the presence of a rewarded box, a condition that more closely resembles the inequity condition. Inequity averse subjects' performance did not differ based on whether the partner was another dog or a box. Moreover, these subjects gave the paw more times when no partner was present and the experimenter mimicked the feeding of a partner than when rewards were placed in the box. These results suggest that responses in the previous studies were inflated by subjects' increased perception of reward attainability when no partner was present and, therefore, over-exaggerated dogs' propensity to give up due to inequity aversion.
狗在没有奖励的情况下，当奖励的同种伙伴不在场时，比在场时更频繁地向实验者伸出爪子，这表明它们厌恶不公平。然而，狗可能更频繁地伸出爪子，而不是厌恶不公平，因为实验者在它们面前移动食物来模拟喂养伙伴的过程。这一动作可以增加动物对获得奖励的感知。我们通过引入一种改进的控制条件来检验这一假设，在这种条件下，当有奖励的盒子存在时，给予爪子的动物不会得到奖励，这种条件更接近不公平条件。厌恶不公平的动物的表现并不取决于同伴是另一只狗还是一个盒子。此外，当没有同伴在场且实验者模仿喂食同伴时，这些动物比当奖励放在盒子里时更频繁地伸出爪子。这些结果表明，在之前的研究中，由于当没有同伴在场时动物对获得奖励的感知增加，反应被夸大，因此夸大了狗因厌恶不公平而放弃的倾向。
