Pigeons only have one adult plumage-they do not alternate breeding and nonbreeding plumages and so have a complete post-breeding molt. Some pigeons have crests or naked skin around the eyes. The gorgeous golden doves of Fiji (genus Ptilinopus) are fiery orange or metallic green and gold. Many species, particularly in the Indo-Pacific, are spectacularly clothed in greens, reds, purples, pinks, blues, and oranges. Combinations of delicate grays, browns, and creams complement the soft plumage. The generally dull plumage of the domestic pigeon is not representative of the huge range of color schemes the order presents. ![]() Two kinds of domestic pigeon produce very peculiar curled "fat quills." These special feathers contain yellow fat that derives from the same cells as powder down. This gives a beautiful soft silky feel to pigeon plumage unmatched by most other birds. These feathers disintegrate to produce a talcum-like powder that the pigeon uses to maintain plumage condition. Powder downs are dispersed over the entire body. Have no or only rudimentary oil glands, glands possessed by most birds which exude an oil used for preening. If grabbed by a predator large numbers of feathers come out in the attacker's mouth and the bird can make its escape. This may be a predator avoidance mechanism. Body feathers have very dense fluffy bases, are loosely attached into the skin, and drop out easily. There is generally no aftershaft, although small ones may be present on some wing and tail feathers. The shaft is generally flattened, strong, and broad then tapers abruptly to a fine point. The tails are of varying lengths, usually shortish, and there are 12–14 tail feathers (up to 18 in Goura and Otidiphaps).īody feathers are unique. Pigeons take off and often fly with a characteristic clapping of wings. Primary feathers are often modified by being variously emarginate (narrowed in their outer sections), but nobody seems to know why they are this shape. The wings have 11 primary feathers, although the first is very reduced, and 10–15 secondaries and tertials, the two being indistinguishable. They have proportionally more wing muscle (31–44% of body weight) compared to most other birds. They can glide and often incorporate this into display flights, but they cannot soar. The wings are usually broad with rounded tips and pigeons are strong direct flyers. The unique pheasant pigeon ( Otidiphaps nobilis) of Papua New Guinea looks and acts like a pheasant and is considered by local people to be megapode and not a pigeon at all. Pigeons are generally very similar in body form although some species resemble quail, partridges, or small turkeys. Generally they possess similar plumage, but some tropical species are sexually dimorphic-the males having quite brilliant plumage. The sexes are similar with males being marginally larger than females. The smallest is the Australian diamond dove ( Geopelia cuneata) which weighs about 1.1 oz (30 g) and the largest the Victoria crowned-pigeon ( Goura victoria) of Papua New Guinea at 3.7–6.6 lb (1.7–3 kg). They are generally compact birds with small- to medium-sized heads held on short but graceful necks. The Columbidae is the only surviving family in the order. Miocene material is also known from Australia and recently from Japan. The order has a somewhat poor fossil history and the oldest species is Columba calcaria from the Miocene of France. They are now considered to be closest to the shorebirds. Sandgrouse (Pterocliformes) have been often considered to be Columbiformes having similar feather structure and musculature but in other respects they are midway between the Columbiformes and the Galliformes. DNA analysis has shown that the Columbiformes have no close relationships with any other birds and their similarities are due to convergence or the retention of primitive characteristics. They differ, however, in biology, behavior, the type of young, and by the fact that pigeons have a specialized backbone and a long hindtoe. They have similar features of the palate, nostrils, wings, voice boxes, and skull. Anatomically the Charadriiformes appear to be the closest. ![]() At various times it has been considered close to the game-birds (Galliformes), parrots (Psittaciformes), or shorebirds (Charadriiformes). The order is generally agreed to be monophyletic (derived from a single common parent form) and does not appear to have clear affinities with any other. ![]() It is a homogenous group of arboreal and terrestrial birds with several unique anatomical and physiological features. This order consists of two families-the pigeons and doves (Columbidae) and the extinct dodos (Raphidae) of the Indian Ocean Mascarene Islands. Number of genera, species 40–45 genera 300–320 species Evolution and systematics Columbiformes Family: Pigeons and Doves Family: Dodos and Solitaires
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