School of Biological Sciences, The University of Queensland, QLD, Australia.
J Evol Biol. 2010 Jul;23(7):1509-18. doi: 10.1111/j.1420-9101.2010.02018.x. Epub 2010 May 26.
Aposematism is defined as the use of conspicuous colouration to warn predators that an individual is chemically or otherwise defended. Mechanisms that drive the evolution of aposematism are complex. Theoretical and empirical studies show that conspicuousness can be either positively or negatively correlated with toxicity as once aposematism is established, species can allocate resources into becoming more conspicuous and/or increase secondary defences. Here, we investigated the evolution of conspicuousness and toxicity in marine opisthobranchs. Conspicuousness of colour signals was assessed using spectral reflectance measurements and theoretical vision models from the perspective of two reef fish signal receivers. The relative toxicity of chemicals extracted from each opisthobranch species was then determined using toxicity assays. Using a phylogenetic comparative analysis, we found a significant correlation between conspicuousness and toxicity, indicating that conspicuousness acts as an honest signal when signifying level of defence and provides evidence for aposematism in opisthobranchs.
警戒色是指利用显著的颜色来警告捕食者，表明个体具有化学或其他形式的防御。驱动警戒色进化的机制很复杂。理论和实证研究表明，警戒色的显著程度与毒性既可以正相关，也可以负相关，因为一旦建立了警戒色，物种就可以将资源投入到变得更加显眼和/或增加次级防御。在这里，我们研究了海洋后腮类软体动物警戒色和毒性的进化。从两种珊瑚礁鱼类信号接收器的角度，利用光谱反射率测量和理论视觉模型来评估颜色信号的显著程度。然后，使用毒性测定法来确定从每个后腮类软体动物物种中提取的化学物质的相对毒性。通过系统发育比较分析，我们发现显著程度和毒性之间存在显著的相关性，这表明当警戒色显著程度表示防御水平时，它可以作为一个诚实的信号，并为后腮类软体动物的警戒色提供了证据。
