Biophysics Group, Institute of Physics, University of Antioquia, Calle 70 #52-21, AA 1226, Medellín, Colombia.
Group of Ecology and Evolution of Vertebrates, Institute of Biology, University of Antioquia, Calle 70 #52-21, AA 1226, Medellín, Colombia.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2018 Dec;204(12):965-975. doi: 10.1007/s00359-018-1295-8. Epub 2018 Oct 8.
The male Anna's hummingbird features a brightly reddish-pink reflecting gorget, due to large stacks of melanosomes in the feather barbules, arranged in layers separated by keratin. Direct observations together with detailed scatterometry demonstrated that the barbules reflect incident light in an approximately specular manner. The structural colouration is iridescent, i.e. varies with a changing angle of light incidence. Spectrophotometrical measurements of the barbule reflectance and absorbance can be well interpreted with calculated spectra obtained with a transfer matrix method for optical multilayers, using anatomical data and measured refractive index spectra. The organization of the reflectors as a Venetian blind presumably functions to create a high spectral contrast of the male's plumage during courtship.
雄安娜蜂鸟的喉胸部有鲜艳的红粉色反光区，这是由于羽毛羽小枝中有大量黑色素体堆积，这些黑色素体排列成层，由角蛋白隔开。直接观察和详细的散射测量表明，羽小枝以近似镜面反射的方式反射入射光。这种结构色是虹彩的，即随光入射角的变化而变化。用转移矩阵法对光学多层膜进行计算得到的光谱，可以很好地解释对羽小枝反射率和吸收率的分光光度测量结果，该方法使用解剖学数据和测量的折射率谱。作为百叶窗的反射器的组织形式可能是为了在求偶期间创造雄性羽毛的高光谱对比度。
