van der Kooi Casper J, Elzenga J Theo M, Dijksterhuis Jan, Stavenga Doekele G
Computational Physics, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
Department of Ecology and Evolution, University of Lausanne, Le Biophore, 1015 Lausanne, Switzerland.
J R Soc Interface. 2017 Feb;14(127). doi: 10.1098/rsif.2016.0933.
Buttercup ( spp.) flowers are exceptional because they feature a distinct gloss (mirror-like reflection) in addition to their matte-yellow coloration. We investigated the optical properties of yellow petals of several and related species using (micro)spectrophotometry and anatomical methods. The contribution of different petal structures to the overall visual signal was quantified using a recently developed optical model. We show that the coloration of glossy buttercup flowers is due to a rare combination of structural and pigmentary coloration. A very flat, pigment-filled upper epidermis acts as a thin-film reflector yielding the gloss, and additionally serves as a filter for light backscattered by the strongly scattering starch and mesophyll layers, which yields the matte-yellow colour. We discuss the evolution of the gloss and its two likely functions: it provides a strong visual signal to insect pollinators and increases the reflection of sunlight to the centre of the flower in order to heat the reproductive organs.
毛茛属（spp.）植物的花朵很特别，因为除了哑光黄色外，它们还具有独特的光泽（类似镜子的反射）。我们使用（显微）分光光度法和解剖学方法研究了几种毛茛属及相关物种黄色花瓣的光学特性。使用最近开发的光学模型量化了不同花瓣结构对整体视觉信号的贡献。我们表明，有光泽的毛茛属花朵的颜色是结构色和色素色罕见组合的结果。非常扁平、充满色素的上表皮充当产生光泽的薄膜反射器，此外还作为由强烈散射的淀粉和叶肉层反向散射的光的过滤器，从而产生哑光黄色。我们讨论了光泽的进化及其两个可能的功能：它为昆虫传粉者提供了强烈的视觉信号，并增加了阳光向花中心的反射，以便加热生殖器官。
