Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Duke University, Durham, NC, 27708, USA.
Sci Rep. 2017 Aug 17;7(1):8504. doi: 10.1038/s41598-017-08435-7.
Chimpanzees and bonobos are highly capable of tracking other's mental states. It has been proposed, however, that in contrast to humans, chimpanzees are only able to do this in competitive interactions but this has rarely been directly tested. Here, pairs of chimpanzees or bonobos (Study 1) and 4-year-old children (Study 2) were presented with two almost identical tasks differing only regarding the social context. In the cooperation condition, players' interests were matched: they had to make corresponding choices to be mutually rewarded. To facilitate coordination, subjects should thus make their actions visible to their partner whose view was partially occluded. In the competition condition, players' interests were directly opposed: the partner tried to match the subject's choice but subjects were only rewarded if they chose differently, so that they benefited from hiding their actions. The apes successfully adapted their decisions to the social context and their performance was markedly better in the cooperation condition. Children also distinguished between the two contexts, but somewhat surprisingly, performed better in the competitive condition. These findings demonstrate experimentally that chimpanzees and bonobos can take into account what others can see in cooperative interactions. Their social-cognitive skills are thus more flexible than previously assumed.
黑猩猩和倭黑猩猩非常善于跟踪他人的心理状态。然而，有人提出，与人类不同，黑猩猩只能在竞争互动中做到这一点，但这很少被直接测试。在这里，成对的黑猩猩或倭黑猩猩（研究 1）和 4 岁的儿童（研究 2）被呈现出两个几乎完全相同的任务，只是在社会背景上有所不同。在合作条件下，玩家的利益是匹配的：他们必须做出相应的选择才能相互奖励。为了便于协调，参与者应该让他们的动作对他们的伙伴可见，而他们的伙伴的视野则部分被遮挡。在竞争条件下，玩家的利益直接对立：伙伴试图匹配参与者的选择，但只有当参与者选择不同时，参与者才会得到奖励，因此他们受益于隐藏自己的动作。这些猩猩成功地根据社会环境调整了他们的决策，并且在合作条件下的表现明显更好。儿童也能区分两种情况，但令人惊讶的是，他们在竞争条件下的表现更好。这些发现通过实验证明，黑猩猩和倭黑猩猩可以在合作互动中考虑到他人能看到的东西。他们的社会认知技能因此比之前假设的更灵活。
