Rapport Munro Emilie, Allritz Matthias, Schweller Kenneth, Haun Daniel B M, Call Josep
School of Psychology and Neuroscience, University of St Andrews, St Andrews, Fife, Scotland.
Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Saxony, Germany.
PLoS One. 2025 Sep 9;20(9):e0329468. doi: 10.1371/journal.pone.0329468. eCollection 2025.
Many animal species live in multi-level societies regulated by complex patterns of dominance. Avoiding competition with dominant group-mates for resources such as food and mates is an important skill for subordinate individuals in these societies, if they wish to evade harassment and aggression. Chimpanzees (Pan troglodytes) are an example of such a species. This study investigated whether chimpanzees could understand the food preferences of their competitors, and make use of this understanding to select non-contested food items. Fifteen chimpanzees were given thorough experience of the differing target preferences of two virtual competitors. In the test, subjects had to select which of the two targets to approach, based on which competitor was present. To choose correctly, they would have to integrate the competitors' preferences from across disparate observations, and then infer, before the competitor acted, what they would do in a novel situation. We also included a control condition featuring two targets for which subjects had no information about the competitors' potential biases. The chimpanzees rapidly learned to direct their virtual agent to collect the targets, and some responded with vocalizations and hard knocking against the screen when competitors "stole" targets from the agent the subject was guiding. However, statistical analyses showed that, both at the individual and the group level, they did not succeed in selecting the correct target item at above-chance levels. Additionally, there was no significant difference between their performance in the test and control. We identify theoretical and methodological discrepancies that could explain the contrasting results of this and other studies.
许多动物物种生活在由复杂的支配模式所调节的多层次社会中。对于这些社会中的从属个体而言，如果它们想避免骚扰和攻击，那么避免与占主导地位的同伴争夺食物和配偶等资源是一项重要技能。黑猩猩（Pan troglodytes）就是这样一个物种的例子。本研究调查了黑猩猩是否能够理解其竞争对手的食物偏好，并利用这种理解来选择无争议的食物项目。让15只黑猩猩充分体验了两个虚拟竞争对手不同的目标偏好。在测试中，受试者必须根据出现的是哪个竞争对手来选择接近两个目标中的哪一个。为了做出正确选择，它们必须整合来自不同观察结果的竞争对手偏好，然后在竞争对手行动之前推断出它们在新情况下会怎么做。我们还纳入了一个对照条件，其中有两个目标，受试者对竞争对手的潜在偏好一无所知。黑猩猩很快学会指挥它们的虚拟代理去收集目标，当竞争对手从受试者所引导的代理那里“偷走”目标时，一些黑猩猩会发出叫声并用力敲打屏幕。然而，统计分析表明，无论是在个体层面还是群体层面，它们在选择正确目标项目方面都没有达到高于随机水平的成功率。此外，它们在测试和对照中的表现没有显著差异。我们指出了一些理论和方法上的差异，这些差异可以解释本研究与其他研究结果的不同。
