Feathers are the things which cover birds. They help keep birds warm. Feathers also protect them from injury. In most kinds of birds, wing feathers help them to fly. These are called flight feathers. Some people have their pet birds clipped. This is a procedure where a vet or a groomer cuts a certain amount of feathers to prevent the bird from flying away or simply for medical reasons.
Feather
Etymology
The Old German noun mhd. veder[e], ahd. fedara is based on the Idg. root pet- "to dash off or down on something, to shoot off, to fly".
Types of feathers
There are two basic types of feathers that differ in construction. These are, on the one hand, the contour feathers, which encompass the exterior of the body, and on the other hand, the down feathers (also called down or down), which are located under the cover feathers and act as a heat-insulating layer. The cover feathers protect the down feathers from moisture.
Contour springs
The contour feathers (pennae conturae) are further subdivided functionally into:
- body feathers (pennae conturae generales): the covering feathers of the trunk
- Wing feathers (Remiges): They form the actual wing of the wing at hand (hand-wings) and forearm (arm-wings)
- Rectrices: the feathers of the tail.
- Tectrices: the remaining feathers on the wings and tail.
Undersprings
The down or downs (plumae) form the undercoat. In some birds (e.g. ratites) they are not present.
The nestling down, the feathers of the young birds, are not real down, but modified contour feathers. They also protect against the cold.
Special springs
In addition to these two basic types, there are also various special springs:
- Semi-downs (Semiplumae): They are situated between contour feathers and downs and are located at the transition to the districts without body feathers.
- Filamentous or hair feathers (filoplumae): Their follicles are well innervated, they serve the proprioception of feathering. Filamentous feathers are absent in ostriches and cassowaries.
- Bristle-feathers (Setae): They replace the eye-lashes, with some bird-types, they are trained as Nasalborsten also at the nostrils.
- Powder feathers (pulviplumae): These are present in some birds (e.g. pigeons, waterfowl) and produce a fine, water-repellent dust of keratin granules.
