Today, the typical feather consists of a central shaft, called a rachis, with serial paired barbs forming a flat, curved surface, which is called a vane.

今天，典型毛包含一个中心轴（轴），还有连续成对形成平坦弯曲表面，这被叶片。

The central part of the feather became a hardened structure called a rachis, with lots of little barbs and barbules, creating the vanes of the feather.

毛中央部分变成了一种轴硬化结构，上面有许多小倒钩和小枝，形成了毛叶片。

So where you see a typical flight feather that has a closed vein and an offset rachis to give it an aerodynamic airfoil shape, the ostrich is have done away with that completely.

所以如你所见这是一个典型飞行毛，有一个封闭静脉和一个偏移轴给它一个符合空气动力学翼型形状，鸵鸟已经完全失去了这种毛了。