Multi-trait mimicry and the relative salience of individual traits

Mimicry occurs when one species gains protection from predators by resembling an unprofitable model species. The degree of mimic-model similarity is variable in nature and is closely related to the number of traits that the mimic shares with its model. Here, we experimentally test the hypothesis that the relative salience of traits, as perceived by a predator, is an important determinant of the degree of mimic-model similarity required for successful mimicry. We manipulated the relative salience of the traits of a two-trait artificial model prey, and subsequently tested the survival of mimics of the different traits. The unrewarded model prey had two colour traits, black and blue, and the rewarded prey had two combinations of green, brown and grey shades. Blue tits were used as predators. We found that the birds perceived the black and blue traits similarly salient in one treatment, and mimic-model similarity in both traits was then required for high mimic success. In a second treatment...

拟态（Mimicry）是指一个物种通过模仿不可食的模型物种来获得捕食者的保护。拟态者与模型物种的相似程度在自然界中存在差异，且与拟态者与模型共享的性状数量密切相关。本研究通过实验验证如下假设：捕食者感知到的性状相对显著性，是拟态成功所需拟态-模型相似程度的重要决定因素。我们操纵了具有两个性状的人工模型猎物的性状相对显著性，并随后测试了不同性状拟态者的存活率。无奖励的模型猎物具有黑色和蓝色两种颜色性状，而有奖励的猎物则具有绿色、棕色和灰色色调的两种组合。实验以蓝山雀（Blue tits）作为捕食者。我们发现，在其中一种处理中，鸟类感知到黑色和蓝色性状具有相似的显著性，此时拟态者需在两个性状上均与模型相似才能获得较高的拟态成功率。在第二种处理中...