Hummingbirds are perhaps the most exquisite bird species because of their prominent iridescence, created by stacks of melanosomes in the feather barbules. The feather colours crucially depend on the nanoscopic dimensions of the melanosome, and the displayed iridescence can distinctly vary, dependent on the spatial organization of the barbs and barbules. We have taken the genus Coeligena as a model group, with species having feathers that strongly vary in their spatial reflection properties. We studied the feather morphology and the optical characteristics. We found that the coloration of Coeligena hummingbirds depends on both the Venetian-blind-like arrangement of the barbules and the V-shaped, angular arrangement of the barbules at opposite sides of the barbs. Both the nanoscopic and microscopic organization of the hummingbird feather components determine the bird's macroscopic appearance.

蜂鸟可能是最精致的鸟类，因为它们显着的虹彩是由羽毛小枝中的黑色素体堆叠形成的。羽毛的颜色主要取决于黑素体的纳米尺寸，并且显示的虹彩可以明显不同，这取决于倒钩和小羽的空间组织。我们将Coeligena属作为一个模型组，具有羽毛的物种在空间反射特性上有很大差异。我们研究了羽毛形态和光学特性。我们发现Coeligena的着色蜂鸟取决于小羽的百叶窗式排列和小羽在倒钩相对两侧的 V 形角度排列。蜂鸟羽毛成分的纳米和微观组织决定了鸟的宏观外观。