Essay On Feathers

Structure of feather – *Feathers are integumentary structures and are characteristic of birds. Feathers are strong, long, elastic, light and water proof. The feathers differ in size, shape and function but are built on the same plan, A typical wing feather is formed of a central, stiff shaft with the softer vanes on each side (Fig. 20.4) *Outer vane is the leading edge of the feather during flight. *The opposite vane is wider than the outer vane which is termed as the inner vane.

20.4 Different types of feathers (A) Quill feather; (B) Filoplume; (C) Down feather Remiges – *Remiges are the large flight feathers of the wing. *Remiges are present in the wings and each wing has twenty three feathers. *Out of 23 remiges, 11 attached to hand called primaries in form of digitals, predigitals, midgitals, metacarpals, addigitals, etc. and remaining 12 connected to forearm to the thumb or pollex called alasupria or bastard wing. *Remiges are attached by ligaments or directly to the bone. *The outer remiges are referred to as the primaries and are the largest and strongest of the flight feathers. *They are responsible for thrust and support during flight and are strong and stiff. *The primaries are at the end of the wing, and are in the same

*Some birds use their tails for leverage, such as woodpeckers, bluebirds, and other cavity-nesting birds that must climb vertical surfaces. In this case, the rectrices are used to apply force against a surface to stabilize the bird. Coverts – *These feathers are found at the bases of wings and tail. *Coverts are smaller forms of contour feathers. *There are several layers of coverts on the wing. *Coverts also cover the ear. *They fill the space between remiges and rectrices.. *The coverts help streamline the shape of the wings and tail while providing the bird with