Data from: Predator perception of Batesian mimicry and conspicuousness in a salamander

In Batesian mimicry a palatable mimic deceives predators by resembling an unpalatable model. The evolution of Batesian mimicry relies on the visual capabilities of the potential predators, as prey detection provides the selective force driving evolutionary change. We compared the visual capabilities of several potential predators to test predictions stemming from the hypothesis of Batesian mimicry between two salamanders: the model species Notophthalmus viridescens, and polymorphic mimic, Plethodon cinereus. First, we found mimicry to be restricted to coloration, but not brightness. Second, only bird predators appeared able to discriminate between the colors of models and non-mimic P. cinereus. Third, estimates of salamander conspicuousness were background-dependent, corresponding to predictions only for backgrounds against which salamanders are most active. These results support the hypothesis that birds influence the evolution of Batesian mimicry in P. cinereus, as they are the only group examined capable of differentiating N. viridescens and non-mimetic P. cinereus. Additionally, patterns of conspicuousness suggest that selection from predators may drive the evolution of conspicuousness in this system. This study confirms the expectation that the visual abilities of predators may influence the evolution of Batesian mimicry, but the role of conspicuousness may be more complex than previously thought.在贝茨拟态（Batesian mimicry）中，可口的拟态类群通过模拟不可口的模型物种来欺骗捕食者。贝茨拟态的演化依赖于潜在捕食者的视觉能力，因为猎物侦测是驱动演化改变的选择压力。我们对比了多种潜在捕食者的视觉能力，以检验两种蝾螈之间贝茨拟态假说的相关预测：模型物种为东部红点蝾螈（Notophthalmus viridescens），多态拟态类群为灰皮螈（Plethodon cinereus）。 首先，我们发现拟态仅局限于体色层面，而非亮度维度。其次，仅鸟类捕食者能够区分模型物种与非拟态灰皮螈的体色。第三，蝾螈的醒目度估计值依赖于背景环境，仅在蝾螈最活跃的生境背景下符合相关预测。 这些结果支持了鸟类影响灰皮螈贝茨拟态演化的假说，因为它们是本次研究中唯一能够区分东部红点蝾螈与非拟态灰皮螈的类群。此外，醒目度的演化模式表明，捕食者的选择压力可能驱动该系统中醒目度的演化。本研究证实了捕食者的视觉能力可能影响贝茨拟态演化的预期，但醒目度的作用可能比此前预想的更为复杂。