Biozentrum Grindel, Department of Biology, University of Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany.
Anim Cogn. 2013 Sep;16(5):755-64. doi: 10.1007/s10071-013-0609-z. Epub 2013 Feb 9.
A comparative approach is required to investigate the evolutionary origins of cognitive abilities. In this paper, we compare the performance of four parrot species, spectacled parrotlets (Forpus conspicillatus), rainbow lorikeets (Trichoglossus haematodus), green-winged macaws (Ara chloroptera) and sulphur-crested cockatoos (Cacatua galerita triton) in standardized string-pulling and string-choice paradigms. We varied the spatial relationship between the strings, the presence of a reward and the physical contact between the string and the reward to test different cognitive skills requiring means-end comprehension. The species tested showed a high individual and inter-specific variation in their ability to solve the tasks. Spectacled parrotlets performed best among the four species and solved the most complex choice tasks, namely crossed-string task and broken-string task, spontaneously. In contrast, macaws and cockatoos failed to identify the correct string in these two tasks. The rainbow lorikeets were outperformed by the parrotlets, but outperformed in turn the macaws and the cockatoos. The findings can be best explained by the variation in social complexity among species, rather than in their ecology.
需要采用比较方法来研究认知能力的进化起源。在本文中，我们比较了四种鹦鹉物种的表现，即眼镜鹦鹉（Forpus conspicillatus）、彩虹吸蜜鹦鹉（Trichoglossus haematodus）、绿翅金刚鹦鹉（Ara chloroptera）和黄冠凤头鹦鹉（Cacatua galerita triton），它们在标准化的拉绳和选绳范式中的表现。我们改变了绳子之间的空间关系、奖励的存在以及绳子和奖励之间的物理接触，以测试需要理解手段-目的关系的不同认知技能。被测试的物种在解决任务的能力方面表现出了很高的个体和种间差异。眼镜鹦鹉在这四个物种中表现最好，能够自发地解决最复杂的选择任务，即交叉绳任务和断绳任务。相比之下，金刚鹦鹉和凤头鹦鹉无法在这两个任务中识别出正确的绳子。彩虹吸蜜鹦鹉的表现优于眼镜鹦鹉，但又优于金刚鹦鹉和凤头鹦鹉。这些发现可以最好地用物种间社会复杂性的变化来解释，而不是用它们的生态来解释。
