Prum Richard O, Quinn Tim, Torres Rodolfo H
Department of Ecology and Evolutionary Biology, and Peabody Museum of Natural History, Yale University, PO Box 208105, New Haven, Connecticut 06250, USA.
J Exp Biol. 2006 Feb;209(Pt 4):748-65. doi: 10.1242/jeb.02051.
The structural colours of butterflies and moths (Lepidoptera) have been attributed to a diversity of physical mechanisms, including multilayer interference, diffraction, Bragg scattering, Tyndall scattering and Rayleigh scattering. We used fibre optic spectrophotometry, transmission electron microscopy (TEM) and 2D Fourier analysis to investigate the physical mechanisms of structural colour production in twelve lepidopteran species from four families, representing all of the previously proposed anatomical and optical classes of butterfly nanostructure. The 2D Fourier analyses of TEMs of colour producing butterfly scales document that all species are appropriately nanostructured to produce visible colours by coherent scattering, i.e. differential interference and reinforcement of scattered, visible wavelengths. Previously hypothesized to produce a blue colour by incoherent, Tyndall scattering, the scales of Papilio zalmoxis are not appropriately nanostructured for incoherent scattering. Rather, available data indicate that the blue of P. zalmoxis is a fluorescent pigmentary colour. Despite their nanoscale anatomical diversity, all structurally coloured butterfly scales share a single fundamental physical color production mechanism - coherent scattering. Recognition of this commonality provides a new perspective on how the nanostructure and optical properties of structurally coloured butterfly scales evolved and diversified among and within lepidopteran clades.
蝴蝶和蛾类（鳞翅目）的结构色归因于多种物理机制，包括多层干涉、衍射、布拉格散射、廷德尔散射和瑞利散射。我们使用光纤分光光度法、透射电子显微镜（TEM）和二维傅里叶分析，研究了来自四个科的12种鳞翅目物种产生结构色的物理机制，这些物种代表了先前提出的蝴蝶纳米结构的所有解剖学和光学类别。对产生颜色的蝴蝶鳞片的TEM进行二维傅里叶分析表明，所有物种都具有适当的纳米结构，能够通过相干散射产生可见颜色，即对散射的可见波长进行差分干涉和增强。此前曾假设美凤蝶（Papilio zalmoxis）的鳞片通过非相干廷德尔散射产生蓝色，但它们的纳米结构并不适合非相干散射。相反，现有数据表明，美凤蝶的蓝色是一种荧光色素颜色。尽管它们在纳米尺度上存在解剖学差异，但所有具有结构色的蝴蝶鳞片都共享一种基本的物理颜色产生机制——相干散射。认识到这种共性为研究结构色蝴蝶鳞片的纳米结构和光学特性在鳞翅目类群之间以及内部如何进化和多样化提供了新的视角。
