羽枝

同样的，绒羽的羽枝簇比拥有羽轴的正羽更早演化出来，因为羽轴是由羽枝脊接合而成。

Likewise , a plumulaceous tuft of barbs evolved before the pennaceous feather with a rachis because the rachis is formed by the fusion of barb ridges .

我们发现羽毛的蓝色纯粹来自于羽枝中的海绵状微结构，而绿色和黄色是由海绵状微结构产生的散射加上表皮中的色素吸收混合而成。

We found that the blue color is purely from the spongy microstructures in the barbs , while green and yellow are produced by the color mixing of the blue color from the spongy microstructures and pigments .

除羽轴外，飞羽的多级羽枝特征尺寸都在微米量级，属于微尺度力学性能测试的范畴。

In addition to the rachis , the feature sizes of multi-level flight feathers barbs are in micron dimension . So the test of barbs is belonging to the category of microscale mechanical testing .