Signals reliably convey information to a receiver. To be reliable, differences between individuals in signal properties must be consistent and easily perceived and evaluated by receivers. Iridescent objects are often striking and vivid, but their appearance can change dramatically with viewing geometry and illumination. The changeable nature of iridescent surfaces creates a paradox: how can they be reliable signals? We contend that iridescent color patches can be reliable signals only if accompanied by specific adaptations to enhance reliability, such as structures and behaviors that limit perceived hue shift or enhance and control directionality. We highlight the challenges of studying iridescence and key considerations for the evaluation of its adaptive significance.

信号可靠地将信息传送到接收器。为可靠起见，信号属性之间的个体差异必须一致，并易于被接收者感知和评估。虹彩物体通常引人注目且生动，但是其外观会随着观察几何体和照明而发生巨大变化。虹彩表面的多变性质造成了一个悖论：它们如何成为可靠的信号？我们认为，虹彩色块只有在进行特定的改编以增强可靠性时才是可靠的信号，例如限制感知色相偏移或增强和控制方向性的结构和行为。我们重点介绍了研究虹彩的挑战以及评估其适应性意义的关键考虑因素。