While traditional economic models assume that agents are self-interested, humans and most non-human primates are social species. Therefore, many of decisions they make require the integration of information about other social agents. This study asks to what extent information about social status and the social context in which decisions are taken impact on reward-guided decisions in rhesus macaques. We tested 12 monkeys of varying dominance status in several experimental versions of a two-choice task in which reward could be delivered to self only, only another monkey, both the self and another monkey, or neither. Results showed dominant animals were more prone to make prosocial choices than subordinates, but only when the decision was between a reward for self only and a reward for both self and other. If the choice was between a reward for self only and a reward for other only, no animal expressed altruistic behaviour. Finally, prosocial choices were true social decisions as they were strikingly reduced when the social partner was replaced by a non-social object. These results showed that as in humans, rhesus macaques' social decisions are adaptive and modulated by social status and the cost associated with being prosocial.

This article is part of the theme issue ‘Existence and prevalence of economic behaviours among non-human primates’.

虽然传统的经济模型假设代理人是自利的，但人类和大多数非人类灵长类动物是社会物种。因此，他们做出的许多决定都需要整合其他社会代理的信息。本研究询问有关社会地位的信息以及做出决定的社会背景信息对恒河猴奖励引导的决定有何影响。我们在两个选择任务的几个实验版本中测试了 12 只不同优势状态的猴子，其中奖励可以只发给自己，只发给另一只猴子，自己和另一只猴子，或者都不给。结果表明，占主导地位的动物比下属更容易做出亲社会的选择，但只有在只对自己的奖励和对自己和他人的奖励之间做出决定时。如果只能在对自己的奖励和对他人的奖励之间做出选择，则没有动物表现出利他行为。最后，亲社会选择是真正的社会决定，因为当社会伙伴被非社会对象取代时，它们会显着减少。这些结果表明，与人类一样，恒河猴的社会决策具有适应性，并受社会地位和与亲社会相关的成本的影响。

本文是主题问题“非人类灵长类动物经济行为的存在和流行”的一部分。