Smirnova Anna A, Cheplakova Maria A, Kubenko Ksenia N
Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119899.
Sci Rep. 2025 May 4;15(1):15569. doi: 10.1038/s41598-025-99778-z.
In a loose-string task an out-of-reach tray baited with food can only be retrieved by simultaneously pulling on both ends of a string threaded through the loops on the tray. This task is used to assess an animal's ability to cooperate, with each animal only having access to one end of the string. Some studies use the loose-string task in a pre-training phase, during which animals are individually taught to pull both ends of the string. Usually, no additional tests are conducted to determine whether the animals have understood how the loose string works. It is conceivable that a lack of knowledge of the causal basis of the loose-string task could make it more challenging to grasp how the partner can assist with it. Here, we tested whether Hooded crows could acquire some knowledge of the causal basis of the loose-string task. Prior to the critical test (Phase 3), the birds were presented with two different tasks (Phase 1 and Phase 2) to allow them to acquire some knowledge of the causal basis of the task. The results may indicate that, as a consequence of the experience gained, some crows may have begun to understand how the loose string works.
在一项松散绳索任务中，一个放置了食物但够不着的托盘，只有同时拉动穿过托盘环扣的绳索两端才能取到。此任务用于评估动物的合作能力，每只动物只能接触到绳索的一端。一些研究在预训练阶段使用松散绳索任务，在此期间单独训练动物拉动绳索两端。通常，不会进行额外测试来确定动物是否理解了松散绳索的工作原理。可以想象，对松散绳索任务因果基础缺乏了解可能会使理解伙伴如何协助完成任务变得更具挑战性。在此，我们测试了秃鼻乌鸦是否能获取一些关于松散绳索任务因果基础的知识。在关键测试（第3阶段）之前，给这些鸟呈现两个不同的任务（第1阶段和第2阶段），以便它们获取该任务因果基础的一些知识。结果可能表明，由于获得的经验，一些乌鸦可能已经开始理解松散绳索的工作原理。
