Data from: Pattern edges improve predator learning of aposematic signals

Edges are salient visual cues created by abrupt changes in luminance and color, and are crucial in perceptual tasks such as motion detection and object recognition. Disruptively colored animals exploit edge detection mechanisms to obscure their body outline and/or to conceal themselves against their background. Conversely, aposematic species may use contrasting patterns with well-defined edges to create highly salient, memorable warning signals. In this study, we investigated how the amount of internal pattern edge, colored area, pattern type or shape repetition of warning signals influenced avoidance learning in the triggerfish, Rhinecanthus aculeatus. Using six different warning signals, we found that fish learnt to avoid aposematic signals faster when they featured more internal pattern edge. We found little evidence that the amount of colored area or pattern type affected learning rates. An optimal amount of pattern edge within a warning signal may therefore improve how warning signals are learnt. These findings offer important insights into the evolution of prey warning signal evolution and predator psychology.边缘是由亮度与色彩突变所产生的显著视觉线索，在运动检测、物体识别等感知任务中发挥着关键作用。破坏性着色动物会借助边缘检测机制，模糊自身躯体轮廓，或是通过与背景相融来隐藏自身。与之相反，警戒色物种（aposematic species）会利用轮廓清晰的高对比度图案，构建出极具显著性且易于记忆的警戒信号。本研究以扳机鱼（Rhinecanthus aculeatus）为研究对象，探讨了警戒信号的内部边缘数量、着色区域面积、图案类型或形状重复度如何影响其回避学习行为。我们设计了6种不同的警戒信号，实验结果显示，当警戒信号拥有更多内部边缘时，扳机鱼能够更快地学会回避这类警戒色信号。研究未发现足够证据表明着色区域面积或图案类型会对学习速率产生影响。由此可见，警戒信号中存在最优的内部边缘数量，可提升该信号的学习效率。本研究结果为猎物警戒信号的演化以及捕食者的心理机制研究提供了重要见解。