Living Links, Yerkes National Primate Research Center , Lawrenceville, GA , USA ; Department of Psychology, Emory University , Atlanta, GA , USA ; Department of Animal Behavior, Ecology & Conservation, Canisius College , Buffalo, NY , USA.
Living Links, Yerkes National Primate Research Center , Lawrenceville, GA , USA.
PeerJ. 2014 Jun 12;2:e417. doi: 10.7717/peerj.417. eCollection 2014.
The purpose of the present study was to push the boundaries of cooperation among captive chimpanzees (Pan troglodytes). There has been doubt about the level of cooperation that chimpanzees are able to spontaneously achieve or understand. Would they, without any pre-training or restrictions in partner choice, be able to develop successful joint action? And would they be able to extend cooperation to more than two partners, as they do in nature? Chimpanzees were given a chance to cooperate with multiple partners of their own choosing. All members of the group (N = 11) had simultaneous access to an apparatus that required two (dyadic condition) or three (triadic condition) individuals to pull in a tray baited with food. Without any training, the chimpanzees spontaneously solved the task a total of 3,565 times in both dyadic and triadic combinations. Their success rate and efficiency increased over time, whereas the amount of pulling in the absence of a partner decreased, demonstrating that they had learned the task contingencies. They preferentially approached the apparatus when kin or nonkin of similar rank were present, showing a preference for socially tolerant partners. The forced partner combinations typical of cooperation experiments cannot reveal these abilities, which demonstrate that in the midst of a complex social environment, chimpanzees spontaneously initiate and maintain a high level of cooperative behavior.
本研究旨在拓展圈养黑猩猩（Pan troglodytes）合作的边界。一直以来，人们对黑猩猩能够自发实现或理解的合作程度存在疑问。如果没有任何预先训练或对伙伴选择的限制，它们能否发展出成功的联合行动？它们能否像在自然环境中那样，将合作扩展到两个以上的伙伴？
黑猩猩有机会与自己选择的多个伙伴合作。小组的所有成员（N = 11）都可以同时使用一个装置，该装置需要两个人（对偶条件）或三个人（三元条件）一起拉动一个装有诱饵的托盘。在没有任何训练的情况下，黑猩猩在对偶和三元组合中自发地总共解决了 3565 次任务。随着时间的推移，它们的成功率和效率有所提高，而在没有伙伴的情况下拉动的次数减少了，这表明它们已经学会了任务的关联。当相似等级的亲属或非亲属在场时，它们更倾向于接近该装置，表现出对社会宽容伙伴的偏好。合作实验中典型的强制性伙伴组合无法揭示这些能力，这表明在复杂的社会环境中，黑猩猩自发地发起并维持高水平的合作行为。
