Eye-spots in Lepidoptera attract attention in humans

Many prey species exhibit defensive traits to decrease their chances of predation. Conspicuous eye-spots, concentric rings of contrasting colours, are one type of defensive trait that some species exhibit to deter predators. We examined the function of eye-spots in Lepidoptera to determine whether they are effective at deterring predators because they resemble eyes (‘eye mimicry hypothesis’) or are highly salient (‘conspicuous signal hypothesis’). We recorded the gaze behaviour of men and women as they viewed natural images of butterflies and moths as well as images in which the eye-spots of these insects were modified. The eye-spots were modified by removing them, scrambling their colours, or replacing them with elliptical or triangular shapes that had either dark or light centres. Participants were generally more likely to look at, spend more time looking at and be faster to first fixate the eye-spots of butterflies and moths that were natural compared with ones that were modified, in...诸多被捕食物种会演化出防御性状，以降低自身被捕食的风险。色彩对比鲜明的同心环状醒目眼斑（eye-spot），乃是部分物种用以威慑捕食者的一类防御性状。本研究以鳞翅目（Lepidoptera）昆虫的眼斑为研究对象，探究其威慑捕食者的功能机制，以明确其起效原理：是通过形似眼部的视觉特征（眼部拟态假说，eye mimicry hypothesis），还是凭借极高的视觉醒目度（醒目信号假说，conspicuous signal hypothesis）。我们记录了男女受试者在观看蝴蝶与飞蛾的自然实景图像，以及此类昆虫眼斑经过人工修改的图像时的注视行为。眼斑的修改方式包括移除眼斑、打乱其原有色彩分布，或是将原眼斑替换为带有深色或浅色中心的椭圆形或三角形图形。总体而言，相较于眼斑经过修改的图像，受试者更易注视天然蝴蝶与飞蛾的眼斑，且注视时长更长、首次注视该类眼斑的反应速度更快，[原文后续内容省略]