Hi Everybody!!

Hi Everybody!!
Welcome to my Hometown!!

Tuesday, July 16, 2013


Hi Everybody!!
Of course, You would find a sunny branch and air out your feathers to dry!  However, humans do not have feathers. Only birds (and some ancient dinosaurs) have feathers. If You can read this Blog, then You have hairs on your skin, not feathers, and You can't fly! Your photostudy tonight is the wet Kites drying their feathers on a sunny branch after my 10 minute rain. Your infostudy from Wikipedia is everything you did not know about about feathers!

All you ever wanted to know about Feathers:


From Wikipedia, the free encyclopedia
Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds and some non-aviantheropod dinosaurs. They are considered the most complex integumentary structures found in vertebrates,[1][2] and indeed a premier example of a complex evolutionary novelty.[3] They are among the characteristics that distinguish the extant Avesfrom other living groups. Feathers have also been noticed in those Theropoda which have been termed feathered dinosaurs. Although feathers cover most parts of the body of birds, they arise only from certain well-defined tracts on the skin. They aid in flight, thermal insulation, waterproofing and coloration that helps in communication and protection.[4]

Feather variations

Structures and characteristics[edit]

Parts of a feather:
1. Vane
2. Rachis
3. Barb
4. Afterfeather
5. Hollow shaft, calamus

Feather structure of a Blue-and-yellow Macaw

Budgerigar feather, magnified, showing interlocking barbules
Feathers are among the most complex integumentary appendages found in vertebrates and are formed in tiny follicles in theepidermis, or outer skin layer, that produce keratin proteins. The β-keratins in feathers, beaks and claws — and the claws,scales and shells of reptiles — are composed of protein strands hydrogen-bonded into β-pleated sheets, which are then further twisted and crosslinked by disulfide bridges into structures even tougher than the α-keratins of mammalian hairhornsand hoof.[5][6] The exact signals that induce the growth of feathers on the skin are not known but it has been found that the transcription factor cDermo-1 induces the growth of feathers on skin and scales on the leg.[7]

Feather microstructure showing interlocking barbules.


There are two basic types of feather: vaned feathers which cover the exterior of the body, and down feathers which are underneath the vaned feathers. The pennaceous feathers are vaned feathers. Also called contour feathers, pennaceous feathers arise from tracts and cover the whole body. A third rarer type of feathers, filoplumes, is hairlike and (if present in a bird) grows along the fluffy down feathers. In some passerines, filoplumes arise exposed beyond the contour feathers on the neck.[1] The remiges, or flight feathers of the wing, and rectrices, the flight feathers of the tail are the most important feathers for flight. A typical vaned feather features a main shaft, called the rachis. Fused to the rachis are a series of branches, orbarbs; the barbs themselves are also branched and form the barbules. These barbules have minute hooks called barbicelsfor cross-attachment. Down feathers are fluffy because they lack barbicels, so the barbules float free of each other, allowing the down to trap much air and provide excellent thermal insulation. At the base of the feather, the rachis expands to form the hollow tubular calamus (or quill) which inserts into a follicle in the skin. The basal part of the calamus is without vanes. This part is embedded within the skin follicle and has an opening at the base (proximal umbilicus) and a small opening on the side (distal umbilicus).[8]
Hatchling birds of some species have a special kind of natal down (neossoptiles) and these are pushed out when the normal feathers (teleoptiles) emerge.[1]
Flight feathers are stiffened so as to work against the air in the downstroke but yield in other directions. It is noted that the pattern of orientation of β-keratin fibers in the feathers of flying birds differs from that in flightless birds. The fibers are better aligned in the middle of the feather and less aligned towards the tips.[9][10]


Feathers insulate birds from water and cold temperatures. They may also be plucked to line the nest and provide insulation to the eggs and young. The individual feathers in the wings and tail play important roles in controlling flight. Some species have a crest of feathers on their heads. Although feathers are light, a bird's plumage weighs two or three times more than its skeleton, since many bones are hollow and contain air sacs. Color patterns serve as camouflage against predators for birds in their habitats, and by predators looking for a meal. As with fish, the top and bottom colors may be different to provide camouflage during flight. Striking differences in feather patterns and colors are part of the sexual dimorphism of many bird species and are particularly important in selection of mating pairs. In some cases there are differences in the UV reflectivity of feathers across sexes even though no differences in color are noted in the visible range.[11] The wing feathers of male Club-winged Manakins Machaeropterus deliciosus have special structures that are used to produce sounds by stridulation.[12]

A contour feather from a Guinea fowl
Some birds have a supply of powder down feathers which grow continuously, with small particles regularly breaking off from the ends of the barbules. These particles produce a powder that sifts through the feathers on the bird's body and acts as a waterproofing agent and a feather conditioner. Powder down has evolved independently in several taxa and can be found in down as well as pennaceous feathers. They may be scattered in plumage in the pigeons and parrots or in localized patches on the breast, belly or flanks as in herons and frogmouths. Herons use their bill to break the feathers and to spread them while cockatoos may use their head as a powder puff to apply the powder.[13] Waterproofing can be lost by exposure to emulsifying agents due to human pollution. Feathers can become waterlogged and birds may sink. It is also very difficult to clean and rescue birds whose feathers have been fouled by oil spills. The feathers of cormorants soak up water and help in reducing buoyancy and thereby allowing the birds to swim submerged.[14]

Rictal bristles of a White-cheeked Barbet
Bristles are stiff, tapering feathers with a large rachis but few barbs. Rictal bristles are bristles found around the eyes and bill. They may serve a similar purpose to eyelashes and vibrissae in mammals. It has been suggested that they may aid insectivorous birds in prey capture or that it may have sensory functions, however there is no clear evidence.[15] In one study, Willow Flycatchers (Empidonax traillii) were found to catch insects equally well before and after removal of the rictal bristles.[16]
Grebes are peculiar in their habit of ingesting their own feathers and also feeding them to their young. Observations on the diet and feather eating frequency suggest that ingesting feathers particularly down from their flanks aids in forming easily ejectable pellets along with their diet of fish.[17]


Feather tracts or pterylae and their naming
Contour feathers are not uniformly distributed on the skin of the bird except in some groups such as the Penguins, ratites and screamers.[18] In most birds the feathers grow from specific tracts of skin called pterylae while there are regions which are free of feathers called apterylae. Filoplumes and down may arise from the apteriae, regions between the pterylae. The arrangement of these feather tracts, pterylosis or pterylography, varies across bird families and has been used in the past as a means for determining the evolutionary relationships of bird families.[19][20]


Colors resulting from different feather pigments
Left: turacin (red) and turacoverdin (green, with some structural blue iridescence at lower end) on the wing of Tauraco bannermani
Right: carotenoids (red) and melanins (dark) on belly/wings of Ramphocelus bresilius
The colors of feathers are produced by pigments, by microscopic structures that can refract, reflect, or scatter selected wavelengths of light, or by a combination of both.
Most feather pigments are melanins (brown and beige pheomelanins, black and grey eumelanins) and carotenoids (red, yellow, orange); other pigments occur only in certain taxa – the yellow to red psittacofulvins[21] (found in some parrots) and the red turacin and green turacoverdin(porphyrin pigments found only in turacos).
Structural coloration[4][22][23] is involved in the production of blue colors, iridescence, most ultraviolet reflectance and in the enhancement of pigmentary colors. Structural iridescence has been reported[24] in fossil feathers dating back 40 million years. White feathers lack pigment and scatter light diffusely; albinism in birds is caused by defective pigment production, though structural coloration will not be affected (as can be seen e.g. in blue-and-white budgerigars).

A feather with no pigment
For example, the blues and bright greens of many parrots are produced by constructive interference of light reflecting from different layers of the structures in feathers, in the case of green plumage in addition to the yellow pigments; the specific feather structure involved is sometimes called the Dyck texture.[25][26] Melanin is often involved in the absorption of some of the light; in combination with yellow pigment it produces dull olive-greens.
In some birds, the feather colors may be created or altered by uropygial gland secretions. The yellow bill colors of many hornbills are produced by preen gland secretions. Other differences that may only be visible in the ultraviolet region have been suggested,[13] but studies have failed to find evidence.[27] Uropygial oil secretion may also have an inhibitory effect on feather bacteria.[28]
A bird's feathers undergo wear and tear and are replaced periodically during its life through molting. New feathers, known as blood, or pin feathers (depending on the stage of growth) when developing, are formed through the same follicle from which the old ones were fledged. The presence of melanin in feathers increases their resistance to abrasion.[29] One study notes that melanin based feathers were observed to degrade more quickly under bacterial action, even compared to unpigmented feathers from the same species, than those unpigmented or with carotenoid pigments.[30] However, another study the same year compared the action of bacteria on pigmentations of two song sparrow species and observed that the darker pigmented feathers were more resistant and they cited other research also published in 2004 that stated increased melanin provided greater resistance. They observed that the greater resistance of the darker birds confirmed Gloger's rule.[31] The evolution of coloration is based on sexual selection and it has been suggested that carotenoid-based pigments may have evolved since they are likely to be more honest signals of fitness because they are derived from special diets,[32][33] or because carotenoids are also required for immune function.[34]

In culture 

During the 18th, 19th, and 20th centuries a booming international trade in plumes, to satisfy market demand in North America and Europe for extravagant head-dressesas adornment for fashionable women, caused so much destruction (for example, to egret breeding colonies) that a major campaign against it by conservationists led to the Lacey Act and caused the fashion to change and the market to finally collapse. Frank Chapman noted in 1886 that as many as 40 species of birds were used in about three-fourths of the 700 ladies' hats that he observed in New York City.[49][50][51]

More recently, rooster plumage has become a popular trend as a hairstyle accessory, with feathers formerly used solely as fishing lures being now used to provide color and style to hair.[52] Modern feather usage in fashion and also adorning military regimental headresses and cloths are derived as a waste product of farming of poultry birds, this includes chicken, geese, turkey, pheasant and ostrich. Feathers used for these purposes are deliberately modified through dyeing and manipulation to enhance the appearance of these poultry feathers, as they are naturally often dull in appearance compared to wild species which they are attempting to mimic. The number of feather products manufacturers in Europe has decreased enormously in the last 60 years mainly due to competition from Asia. One surviving company Jaffe et fils founded in 1946, formerly of London now based in Axminster, Devon is one of the last in Europe to dye and manufacture feather products for fashion, theatre and military regalia. Feathers have adorn hats at many prestigious events such as Weddings and Ladies day at Race courses(Royal Ascot). One milliner, Philip Treacy, has specialized in the use of feathers. He has created highly regarded hats notably for the Royal Family. One such as the hat was worn by the Camilla now the Duchess of Cornwall on her marriage to Prince Charles.

The Kites Dry Out the Feathers:

The second one:

...this is brendasue signing off from Rainbow 

Creek. See You next time! Have a good week!