The Hakubi Center for Advanced Research, Kyoto University, Yoshida-honmachi, Kyoto 606-8501, Japan.
Curr Biol. 2020 Jul 6;30(13):2616-2620.e2. doi: 10.1016/j.cub.2020.04.062. Epub 2020 May 14.
Many animals produce vocal alarm signals when they detect a predator, and heterospecific species sharing predators often eavesdrop on and respond to these calls [1]. Despite the widespread occurrence of interspecific eavesdropping in animals, its underlying cognitive process remains to be elucidated. If alarm calls, like human referential words, denote a specific predator type (e.g., "snake!"), then receivers may retrieve a mental image of the predator when hearing these calls [2-4]. Here, using a recently developed experimental paradigm [5], I test whether heterospecific alarm calls evoke a predator-specific visual search image in wild birds. During playback of snake-specific alarm calls produced by Japanese tits (Parus minor), coal tits (Periparus ater) approach a wooden stick being moved in a snake-like manner. However, coal tits do not approach the same stick when hearing other call types or if the stick's movement is dissimilar to that of a snake. Thus, Japanese tit snake alarms cause coal tits to specifically enhance visual attention to snakelike objects. These results provide experimental evidence for the evocation of visual search images by heterospecific alarm calls, highlighting the importance of integrating cross-modal information in interspecific eavesdropping.
许多动物在探测到捕食者时会发出声音警报信号，而具有共同捕食者的异源物种通常会偷听并对这些叫声做出反应[1]。尽管动物之间的偷听现象普遍存在，但它的潜在认知过程仍有待阐明。如果警报声像人类的指示词一样，表示特定的捕食者类型（例如“蛇！”），那么当听到这些叫声时，接收者可能会在脑海中浮现出捕食者的形象[2-4]。在这里，我使用一种新开发的实验范式[5]，测试了异源警报声是否会在野生鸟类中引发特定于捕食者的视觉搜索图像。在播放日本山雀（Parus minor）发出的特定于蛇的警报声时，煤山雀（Periparus ater）会接近以蛇形方式移动的木棍。然而，当听到其他叫声类型或当木棍的移动方式与蛇不同时，煤山雀不会接近同一根木棍。因此，日本山雀的蛇警报声导致煤山雀特别关注蛇形物体。这些结果为异源警报声引发视觉搜索图像提供了实验证据，突出了在异源偷听中整合跨模态信息的重要性。
