Data from: Discrete colour polymorphism in the tawny dragon lizard (Ctenophorus decresii) and differences in signal conspicuousness among morphs

Intraspecific colour variation is common in nature and can vary from the coexistence of discrete colour variants in polymorphic species to continuous variation. Whether coloration is continuous or discrete is often ambiguous and many species exhibit a combination of the two. The nature of the variation (discrete or continuous) has implications for both the genetic basis of the colour variation and the evolutionary processes generating and maintaining it. Consequently, it is important to qualify the existence of discrete morphs, particularly in relation to the animal's visual system. In this study, we quantified male throat colour variation in Ctenophorus decresii tawny dragon lizard and tested for morphological and ecological correlates of the colour variants. We confirmed that discrete throat colour morphs can be defined based on colour and pattern analyses independent of the human visual system. We also found that the colour variants differed in their conspicuousness from the background, to the lizard's visual system, which has implications for signalling. However, the morphs did not differ in morphology or microhabitat use, which suggests that these characteristics are not involved in the evolutionary maintenance of the polymorphism.

种内体色变异在自然界中普遍存在，其表现形式涵盖多态物种中离散体色形态的共存，到连续渐变的体色变异谱系。体色变异究竟属于连续型还是离散型，往往难以明确界定，诸多物种同时兼具两种变异模式的特征。体色变异的类型（离散或连续），既与该变异的遗传基础密切相关，也会影响其产生与维持的进化进程。因此，准确界定离散体色形态的存在至关重要，尤其是需结合动物自身的视觉系统进行判定。本研究对德氏黄褐色飞龙蜥（Ctenophorus decresii）的雄性喉部体色变异进行了量化分析，并检验了该体色变异与形态学、生态学特征的关联。本研究证实，可脱离人类视觉系统，仅基于体色与斑纹分析，即可界定离散的喉部体色形态。同时发现，基于该蜥的视觉系统来看，不同体色形态与背景的显眼程度存在显著差异，这一结果对动物信号通讯研究具有启示意义。但不同体色形态在形态特征与微生境利用方面并无显著差异，这表明上述两类特征并未参与该体色多态的进化维持过程。