The Hierarchical Structures of Feathers (image) Chinese Academy of Sciences Headquarters Share Print E-Mail Caption (A) The vane consists of a number of side branches, which are aligned in parallel and are called barbs. (B) The adjacent barbs overlap closely, forming the dense vane. The second-order side branches, called barbules, occur on both sides of barbs. (C and D) The hooklets from one barb hook the adjacent barbs and fasten the vane. (E ) Stereoscopic structure of a feather obtained via 3D reconstruction with a micro X-ray microscope. The hooklets hook the curved margin of the barbules on the adjacent barbs. Finer toothlike spine structures can be observed. (Scale bars: A, 3 cm, and Inset, 5 mm; B, 500 μm; C, 200 μm; D, 50 μm.) Credit TIPC Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.