Limongelli L, Boysen S T, Visalberghi E
Dipartimento di Biologia Animale e dell'Uomo, Università di Roma La Sapienza, Italy.
J Comp Psychol. 1995 Mar;109(1):18-26. doi: 10.1037/0735-7036.109.1.18.
Five chimpanzees (Pan troglodytes) were tested to assess their understanding of causality in a tool task. The task consisted of a transparent tube with a trap-hole drilled in its middle. A reward was randomly placed on either side of the hole. Depending on which side the chimpanzee inserted the stick into, the candy was either pushed out of the tube or into the trap. In Experiment 1, the success rate of 2 chimpanzees rose highly above chance, but that of the other subjects did not. Results show that the 2 successful chimpanzees selected the correct side for insertion beforehand. Experiment 2 ruled out the possibility that their success was due to a distance-based associative rule, and the results favor an alternative hypothesis that relates success to an understanding of the causal relation between the tool-using action and its outcome.
对五只黑猩猩（黑猩猩属）进行了测试，以评估它们在工具任务中对因果关系的理解。该任务包括一根透明管，管中间钻有一个陷阱孔。奖励被随机放置在孔的两侧。根据黑猩猩将棍子插入哪一侧，糖果要么被推出管子，要么掉进陷阱。在实验1中，两只黑猩猩的成功率大幅高于随机水平，但其他受试者的成功率则没有。结果表明，这两只成功的黑猩猩事先选择了正确的插入侧。实验2排除了它们成功是由于基于距离的关联规则的可能性，结果支持了另一种假设，即成功与对工具使用动作及其结果之间因果关系的理解有关。
