Mangile's Pigeon Pages
American Pigeon Journal
August 1990, pages 26, 27 & 28 .
(With minor additions.)
Are We Winning the War on Whorls?
by Robert J. Mangile
Whorls In General
What in the World is a Whorl? To pigeon fanciers, it is the word or term used in a general sense, to describe a "cowlick" expression of feathers on a pigeon. A swirling or fan-like appearance with a visible or an anticipated center. Card-sharks display a portion of a whorl when they expertly fan a deck of cards in one hand.
Classic examples of whorling in pigeons can be found in the hood of a Jacobin or the rosette on the forehead of a Bokhara Trumpeter. The "cowlick" appearance in each case appears as a complete circle. But, other examples of feather whorling, in varying degrees of completeness, also exist on pigeons.
Verbal descriptions of whorling are difficult. Please try to follow along cautiously. Perhaps something stated may shed some light that will open a new door towards a better understanding of whorling!
The present day general consensus seems to be that whorled feathers grow in reversed or partially reversed positions. In my opinion, that description is not accurate enough. Yet, it is not entirely incorrect because some feathers appear growing exactly 180 degrees in the opposite direction.
To begin the discussion it seems pertinent to acknowledge the obvious; i.e., that all the feathers on a normal pigeon grow in contour with the body from the head to the tail. Pin feathers can also be seen growing out of the skin in that normal fashion; i.e., pointing toward the tail-end (posterior) of the bird.
Further, the feathers grow in restricted areas called pterylae or "feather tracts". Areas where feathers do not grow are called apteria. For example: the "featherless" tract which borders and includes the breast bone, or keel, is called the "sternal apterium". This is the area that brooding birds touch to their eggs and is often called the "brood patch". This featherless tract extends from the upper crop to the vent. There is a similar featherless tract on the mid-line of the back, as well as in other areas on the skin. A close inspection of a squab in pin feathers should reveal areas of where feathers do and do not grow.
In discussing whorls, the "peak crest" offers a good place to begin. To most, a peak crest doesn't appear as a product of whorling. But, after extensive fumbling around, trying to examine pin feathers and whorled plumages, my impressions convinced me that crests are products of whorls.
If we carefully and thoughtfully examine a peak crest, it becomes quite clear that the feathers on the neck are increasingly twisted and raised upward and inward, away from the back of the neck. That is to say..., the feathers on the lower end of the neck and upper back are nearly in their normal position and progressing upward to the back of the head they progressively increase their twisting, angular direction upward and inward - towards the median line from each side of the bird.
The summit of the crest possesses the feathers with the greatest degree of divergence from the normal contour arrangement of feathers. It is important to point out that feathers involved in a peak crest are not reversed; but are gradually increasing in their reversal of direction from the back of the neck to the peak. Even the feathers at the summit of the peak are not reversed yet.
However, when we examine a fully expressed shell crest, as in the Komorner Tumbler, we find that the feathers involving the shell portion of the crest are dramatically turned upward. These feathers might be considered "reversed" because they display the "true underside" of the feathers "inside" the shell. Normal neck feathers display an iridescent reddish-green on their surface; and the "outer shell" feathers display an iridescence - implying that the feather has completely been turned into a reversed position at the top of the crest. To help understand this point, try holding your hands in front of you with your palms (representing the bottom of feathers) down and your thumbs touching together at a place representing the median line. Then roll both hands simultaneously bringing the thumbs upwards, eventually looking into the palms of both hands. Your palms (representing the bottom of feathers) are now on the inside of the shell crest.
(To assist the reader, references will be made to photos in W. M. Levi's book, "Encyclopedia of Pigeon Breeds".) Compare the non iridescent "inner shell" of the Bokhara Trumpeter, (Fig. 526, p.504) with the lustrous iridescence of the "outer shell" on the German Double-Crested Trumpeter, (Fig. 537, p.515). This iridescent sheen can be seen on the outer back of a shell crest but not on the inner back of the shell; confirming that the feather has been twisted around. This sheen is also visible on the neck feathers involving the crest, e.g. the shell crest of the Koros Tumbler, (Fig. 675, p.645) and the peak crest of the Berne White Tail, (Fig. 498, p.479).
It must be pointed out that in a fully developed shell crest, we can often see the visual "center" of a whorl someplace below the back of the head; or upper neck, beneath the eye. From that center all the feathers are gradually twisted into a swirl or whorl.
The feathers nearer the head are shorter feathers than those on the neck; therefore, the shell appears to stop at the center of the whorl on the side of the head. The small feathers at the anterior (front) edge of the whorl are twisted to almost a full turn or 360 degrees, as displayed by the white German Double-Crested Trumpeter, (Fig. 538, p.515). They are not simply reversed as the unexplained word might suggest but are gradually twisted and rotated.
It is important to recognize that the crest, (either shell or peak), is comprised of feathers merging from both sides of the bird. It is of utmost importance to understand that the feathers on the right side of the bird, swirl into a clockwise direction. That is..., they gradually twist and rotate clockwise increasingly upward into relatively reversed positions. Whereas; the feathers on the left side are swirled into a counterclockwise direction. The opposite directions of the swirls merge at the median line and produces a crest.
The full circular rosette of the Bokhara Trumpeter appears to be a single entity. It isn't! It is basically derived from two halves merging at the median line. It is not a single whorl but a combined affect from two partially expressed whorls at the median line. The feathers at the back (posterior) of the rosette are rotated 360 degrees, those on the sides are rotated 270 degrees and those in front (anterior) are rotated 180 degrees (reversed?). Each half (right and left) have opposite rotations (right = clockwise; left = counterclockwise) and together each half compliments the other in the display of a uniform looking rosette.
This directional rotation of feathers can be seen in the "crop frill" of the Oriental Frill and the Chinese Owl. The vertical frill on the crop of the Oriental Frill is produced by the rotation of feathers along the edge of the apterium. Those feathers on the right half are rotated clockwise in varying degrees. Feathers on the left are rotated counterclockwise.
The Chinese Owl has a vastly expanded version of the frilled neck. The close examination of the horizontal breast frill will reveal a similar rotation of feathers found in the vertical frill. Feathers at the sides of the breast frill gradually rotate outward and then gradually upward toward the upper portion of the frill. The feathers at the top of the frill, at the median line, are rotated 180 degrees (reversed). The contour of the feathers clearly indicate that they belong in a downward position.
The breast frill phenomenon rotates (reverses) feathers on the upper crop and neck. This twisting, rotation extends to the upper neck to produce a "collar" which extends to the back of the head. The examination of these feathers suggest that those at the front (anterior) of the collar, (those forming the "V" beneath the bill) have been rotated out and upward. (In affect it is equal to a crest on the birds neck!) The sheen on the surface of normal feathers can be seen on those of the collar, indicating that they are indeed growing with their normal surface area facing outward but rotated 180 degrees, as seen on the blue check Chinese Owl hen, (Fig. 318, p.311).
The hood, mane and chain of the Jacobin comprise the most classic combination of whorls found in domestic pigeons! A breed characteristic of the Jacobin that draws very little recognition is the length of it feathers. I believe this to be at least one of three basic elements involved in the hood and gives it height. The two other elements, i.e., the collar, (as in the Chinese Owl), and the modified shell crest, are combined with the long feather quality that produces the hood.
There are many other forms of whorls and twisted feathers displayed in several breeds. Some forms are found in mongrels or occur somewhat spontaneously in bonafied breeds. For example; I had an indigo checked Racing Homer hen that displayed ruffles on the insides of it legs; which were quite visible in given situations. Some other rather well known whorl-like forms are: "eyebrows" (Fig. 655, p.626), "nasal-tuft" (Fig. 558, p.535), "sideburns" (Fig. 804, p.766) and "pantaloons" of Chinese Owls (Fig. 319, p.312).
The Capuchin (Fig. 68, p.91), appears to lack the Owl-like "neck collar" but has a vastly modified expression of the shell crest. The Mane Pigeon (Fig. 291, p.289), appears(?) to possess both, the collar and shell crest. The Saint (Fig. 431, p.418) and the Leonardo (Fig. 233, p.230) are attempts to develop new breeds from crosses involving the Jacobin. Concerning the Leonardo, Levi states..., "This breed is an interesting example of an asymmetrical character, which is a rarity in nature."
The extremely "curled" feathers of the Frillback (Fig. 123, p.137) and the slightly curled or "fluted" feathers of the Ptarmigan (Fig. 415, p. 403) are not the results of whorling.
It is not the aim of this article to explain away all the feather whorling occurring on domestic pigeons; but rather to enlighten others of what seems to be a valid observation; which suggests that all the feathers involved in a "whorl" have a directional twisting and rotation, relevant to the side of the bird. Whorls on the right half of the bird rotate clockwise and those on the left half rotate counterclockwise.
It must be said that the direction of the feathers are relative to the direction of their emergence from the skin. By observing the pin-feathered squabs of breeds that display whorling, it becomes clear that the feathers are growing in abnormal whorled positions in the skin. It would seem that any serious study would have to consider the skin as the prime area of investigation.
Discussing the genetics of whorls has been deliberately omitted; partly due to conflicting breeding results. Anyone serious about solving the mysteries of whorling should be prepared to face frustration. It would seem to me that the combination of the Chinese Owl's collar and the Komorner Tumbler's shell crest is capable of producing a Jacobin-like hood. On the surface, this would seem easily settled with a couple of Komorner x Chinese Owl crosses and a large production of their F2's. Good luck! And don't forget to report your results, even if it isn't what you expect.
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