774 Extreme organization of supra-basal cells allows the building of modular feather architectures for adaptable flight

The skin forms the interface between an organism and its environment. To venture into diverse eco-spaces, animals evolve different integumentary organs to adapt. Here we study how feathers are made from a flat epidermis. A feather is made of two modules: a central shaft (rachis) and the bilateral vane which is made of barb branches. The feather has to be light and strong. In the follicle, feather epidermis first forms an epithelial cylinder with...