Bird

Bird diseases that can be contracted by humans include psittacosis, salmonellosis, campylobacteriosis, Newcastle's disease, mycobacteriosis (avian tuberculosis), avian influenza, giardiasis, and cryptosporidiosis. However, there is a considerable professional competition dominated by younger men and women. Colorful, particularly tropical, birds (e.g., parrots, and mynahs) are often kept as pets although this practice has led to the illegal trafficking of some endangered species; CITES, an international agreement adopted in 1963, has considerably reduced trafficking in the bird species it protects. Because of its relaxed pace and comparatively light physical demands, it is a popular participant sport, particularly for the elderly. As birds are very sensitive to toxins, the Canary was historically used in coal mines to indicate the presence of poisonous gases, allowing miners sufficient time to escape without injury. Bowls is popular in the United Kingdom, Australia, New Zealand, Canada, and parts of the United States. Chickens and pigeons are popular as experimental subjects, and are often used in biology and comparative psychology research. Teams "holding shot" with the closest bowl will often make their subsequent shots not with the goal of placing the bowl near the jack, but in positions to make it difficult for opponents to get their bowls into the head, or to places where the jack might be deflected to if the opponent attempts to disturb the head.

Falcons are still used for hunting, while cormorants are employed by fishermen. Particularly in team competition there can be a large number of bowls on the green towards the conclusion of the end, and this gives rise to complex tactics. For example, Homing pigeons were commonly used to carry messages before the advent of modern instant communications methods (many are still kept for sport). The challenge in all these shots is to be able to adjust line and length accordingly, the faster the delivery, the narrower the line or "grass". Other birds have long been used by humans to perform tasks. An "upshot" or "yard on" shot involves delivering the bowl with an extra degree of weight, enough to displace the jack or disturb other bowls in the head without killing the end. In North America, introduced House Sparrows, Common Starlings, and House Finches are similarly widespread. A "drive" involves bowling with considerable force with the aim of knocking either the jack or a specific bowl out of play - and with the drive's speed, there is virtually no noticeable curve on the shot.

For example, the common pigeon or Rock Dove (Columba livia) thrives in urban areas around the world. In both cases, the bowl is rolled as close to the jack as possible, unless tactics demand otherwise. Numerous species have come to depend on human activities for food and are widespread to the point of being pests. The same bowler can deliver a "backhand draw" by turning the bowl over in his hand and curving it the opposite way, from left to right. Many species have become extinct through over-hunting, such as the Passenger Pigeon, and many others have become endangered or extinct through habitat destruction, deforestation and intensive agriculture being common causes for declines. For a right-handed bowler, "forehand draw" is initially aimed to the right of the jack, and curves in to the left. At one time swans and flamingos were delicacies of the rich and powerful, although these are generally protected now. "Draw" shots are those where the bowl is rolled to a specific location without causing too much disturbance of bowls already in the head.

Other birds that have been utilized for food include emus, ostriches, pigeons, grouse, quails, doves, woodcocks, songbirds, and others, including small passerines such as finches. When bowling there are several types of delivery. The most commonly eaten species is the domestic chicken and its eggs, although geese, pheasants, turkeys, and ducks are also widely eaten. They have unique symbol markings to identify competitors' bowls, and by regulation have a diameter of about 15 centimetres. Birds are an important food source for humans. Usually coloured black, bowls are now available in a variety of colours including a range of fluorescent colours. This region is sometimes featherless, and the skin may be tinted (as in many species of the cormorant family). They were originally made from lignum vitae, a dense wood giving rise to the term "woods" for bowls, but are now more typically made of a hard plastic composite material.

The region between the eye and bill on the side of a bird's head is called a lore. Regulations determine minimum and maximum curvature characteristics allowed, but within these rules bowlers can and do choose bowls to suit their own preference. See bird skeleton.. A bowler can recognise the bias direction of the bowl in his hand by a dimple or symbol on one side. Birds also have skeletons possessing unique characteristics. This is no longer permitted by the rules and bias is now produced entirely by the shape of the bowl. The use of gizzard stones is a similarity between birds and dinosaurs, which left gizzard stones called gastroliths as trace fossils. Bowls are designed to travel a curved path, referred to as bias, and was originally produced by inserting weights to one side of the bowl.

For birds in captivity, only certain species of birds require grit in their diet for digestion. The team captain or "skipper" always plays last and is instrumental in directing his team's shots and tactics. Depending on the species, the gizzard may contain small pieces of grit or stone that the bird has swallowed to aid in the grinding process of digestion. In these, teams take turns to bowl, with each player within a team bowling all their bowls, then handing over to the next player. Birds possess a ventriculus, or gizzard, that is composed of four muscular bands that act to rotate and crush food by shifting the food from one area to the next within the gizzard. As well as singles competition, there can be pairs, triples and four-player teams. The active phase of respiration in birds is exhalation, requiring effort of the musculature. Some competitions use a "set" scoring system, with the first to seven points awarded a set in a best-of-five set match.

A diaphram is absent in birds; the entire body cavity acts as a bellows to move air through the lungs. Scoring systems vary from competition to competition, with some being the first to a specified number of points, say 21, or the highest scorer after say, 21 ends. Air flows through the honeycombed walls of the parabronchi and into air capillaries, where oxygen and carbon dioxide are traded with cross-flowing blood capillaries by diffusion. The exercise is then repeated for the next end. Avian lungs do not have alveoli, as mammalian lungs do, but instead contain millions of tiny passages known as parabronchi, connected at either ends by the dorsobronchi and ventrobronchi. For instance, if a competitor has bowled two bowls closer to the jack than their competitor's nearest, they are awarded two points. Thus the partial pressure of oxygen in a bird's lungs is the same as the environment, and so birds have more efficient gas-exchange of both oxygen and carbon dioxide than do mammals. After each competitor has delivered all of their bowls (four each in singles), the distance of the closest bowls to the jack is determined (the jack may have been displaced) and points are awarded for each bowl which a competitor has closer than the opponent's nearest to the jack.

Since during inhalation and exhalation fresh air flows through the lungs in only one direction, there is no mixing of oxygen rich air and carbon dioxide rich air within the lungs as in mammals. Similarly if the jack is knocked into the ditch it is still alive unless it is out of bounds to the side resulting in a "dead" end which is replayed. Air flows through the air sacs and lungs as follows:. "Touchers" are marked with chalk and remain alive in play even though they are in the ditch. It takes a bird two full breaths to completely cycle the air from each inhalation through its lungs and out again. Bowls reaching the ditch are dead and removed from play, except in the event when one has "touched" the jack on its way. There are three distinct sets of organs involved in respiration:. Once it has come to rest, the players take turns to roll their bowls from the mat towards the jack and thereby build up the "head".

In addition to the lungs themselves, birds have posterior and anterior air sacs (typically nine) which control air flow through the lungs, but do not play a direct role in gas exchange. In the simplest competition, singles, one of the two opponents begins a segment of the competition (in bowling parlance, an "end"), by placing the mat and rolling the jack to the other end of the green as a target. Birds ventilate their lungs by means of crosscurrent flow: the air flows at a 90° angle to the flow of blood in the lungs' capillaries. The game is usually played on a large, rectangular, precisely levelled and manicured grass or synthetic surface known as a bowling green, but an indoor variation on carpet is also played. In other words, in bird species in which male incubation is common, females tend to select mates on the basis of parental behaviors rather than physical appearance. . "This information then suggests that sexual selection may be less intense in taxa where males incubate, hypothetically because males allocate more effort to parental care and less to mating" (Ketterson and Nolan, 1994). This game is most popular in Australia, Canada, the United Kingdom and in other UK territories.

This extreme loss of mating opportunities leads to a reduction in reproductive success among incubating males. It is related to bocce and pétanque. It takes time and also may require physiological changes that interfere with continued mating. Bowls (also known as Lawn Bowls or Lawn Bowling) is a precision sport where the goal is to roll slightly radially asymmetrical balls (called bowls) closer to a smaller white ball (the "jack" or "kitty") than one's opponent is able to do. Interestingly, male incubation is the most confining male parental behavior. The parental behavior most closely associated with monogamy is male incubation.

"In one form of monogamy such as with obligate monogamy a female cannot rear a litter without the aid of a male" (Gowaty, 1983). In birds, male care can be seen as important or essential to female fitness. In most groups of animals, male parental care is rare, but in birds it is quite common; in fact, it is more extensive in birds than in any other vertebrate class. One reason for the high rate of monogamy among birds is the fact that male birds are just as adept at parental care as females.

In some cases, the individuals may pair for life. Monogamous species of males and females pair for the breeding season. Polygyny constitutes 2% of all birds and polyandry is seen in less than 1%. Monogamy is seen in approximately 91% of all bird species.

The three mating systems that predominate among birds are polyandry, polygyny, and monogamy. Sources for this section include:. Some birds, such as pigeons, geese, and Red-crowned Cranes, remain with their mates for life (or for a long period) and may produce offspring on a regular basis. The process whereby a chick acquires feathers until it can fly is called "fledging".

The young of hole-nesters, on the other hand, are often totally incapable of unassisted survival. The chicks of many ground-nesting birds such as partridges and waders are often able to run virtually immediately after hatching; such birds are referred to as nidifugous. Precocial birds can care for themselves independently within minutes of hatching; altricial hatchlings are helpless, blind, and naked, and require extended parental care. After the eggs hatch, parent birds provide varying degrees of care in terms of food and protection.

The avian phallus differs from the mammalian penis in several ways, most importantly in that it is purely a copulatory organ and is not used for expelling urine. Except during copulation, it is hidden within the proctodeum compartment within the cloaca, just inside the vent. Many waterfowl and some other birds, such as the ostrich and turkey, do possess a phallus. The eggs will then continue their development in the nest.

Then, one by one, eggs will descend from the female's ovaries and become fertilized by the male's sperm, before being subsequently laid by the female. The sperm is stored in the female's cloaca for anywhere from a week to a year, depending on the species of bird. This can happen very fast, sometimes in less than one second. He moves the opening of his cloaca, or vent, close to hers, so that the sperm can enter the female's cloaca, in what is referred to as a cloacal kiss.

During copulation, the female moves her tail to the side and the male either mounts the female from behind or moves very close to her. In the males of species without a phallus (see below), sperm is stored within the proctodeum compartment within the cloaca prior to copulation. The female's ovaries also become larger, although only the left ovary actually functions. Although most male birds have no external sex organs, the male does have two testes which become hundreds of times larger during the breeding season to produce sperm.

See also: Sibley-Ahlquist taxonomy. However, scientists are not in agreement as to the relationships between the orders; evidence from modern bird anatomy, fossils and DNA have all been brought to bear on the problem but no strong consensus has emerged. A preponderance of evidence seems to suggest that the modern bird orders constitute accurate taxa. Sibley & Ahlquist's Phylogeny and Classification of Birds (1990) is a landmark work on the classification of birds (although frequently debated and constantly revised).

The classification of birds is a contentious issue. See the chart for more information. The basal divergence from the remaining Neognathes was that of the Galloanseri, the superorder containing the Anseriformes (ducks, geese and swans), and the Galliformes (the pheasants, grouse, and their allies). Some scientists suspect that the ratites represent an artificial grouping of birds which have independently lost the ability to fly, while others contend that the ratites never had the ability to fly and are more directly related to the dinosaurs than other modern birds.

The ratites are large flightless birds, and include ostriches, cassowaries, kiwis and emus. The paleognaths include the tinamous (found only in Central and South America) and the ratites. Modern birds are classified in Neornithes, which are split into the Paleognathae and Neognathae. In fact, the bird-like hip structure also developed a third time among a peculiar group of theropods, the Therizinosauridae.

It should be noted that although ornithischian (bird-hipped) dinosaurs share the same hip structure as birds, birds actually originated from the saurischian (lizard-hipped) dinosaurs, and thus arrived at their hip structure condition independently. Evidence for this theory is currently inconclusive, but digs continue to unearth fossils (especially in China) of the strange feathered dromaeosaurs. dromaeosaurs evolved from birds and not the other way around. Because of this, some paleontologists have suggested that dromaeosaurs are actually basal birds whose larger members are secondarily flightless, i.e.

In fact, Cryptovolans makes a better "bird" than Archaeopteryx which is missing some of these modern bird features. The recently discovered dromaeosaur, Cryptovolans, was capable of powered flight, contained a keel and had ribs with uncinate processes. Other Mesozoic birds include the Confuciusornithidae, Enantiornithes, Ichthyornis, and Hesperornithiformes, a group of flightless divers resembling grebes and loons. It remains the most primitive known bird.

The basal bird Archaeopteryx, from the Jurassic, is well-known as one of the first "missing links" to be found in support of evolution in the late 19th century. Recent discoveries in northeast China (Liaoning Province) demonstrating that many small theropod dinosaurs had feathers contribute to this ambiguity. As more non-avian theropods that are closely related to birds are discovered, the formerly clear distinction between non-birds and birds becomes less so. Specifically, birds are members of Maniraptora, a group of theropods which includes dromaeosaurs and oviraptorids, among others.

Birds are generally considered to have evolved from theropod dinosaurs. A more recent, radically different classification based on molecular data has been developed (the so-called Sibley order) and is gaining acceptance. Note: This is the traditional classification (the so-called Clements order). Neognathae:.

Paleognathae:. The list of birds gives a more detailed summary, including families. This is a list of the taxonomic orders in the class Aves.
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The class of birds separated early into two superorders, the Paleognathae (mostly flightless birds like ostriches), and the wildly diverse Neognathae, containing all other birds. According to the most recent consensus, Class Aves and a sister group, the family Crocodylidae, together form a group of unnamed rank, the Archosauria. The founding species of class Aves probably lived in the Jurassic period. Birds form a class, whose scientific name is Aves.

. Hundreds of academic journals and thousands of scientists are devoted to bird research, while amateur enthusiasts (called birdwatchers or, more commonly, birders) probably number in the millions. Birds are among the most extensively studied of all animal groups. The Great Auk, flightless rails, and the moa of New Zealand, for example, all became extinct due to human influence.

Flightless species are vulnerable to extinction when humans or the mammals they introduce arrive in their habitat. Flightless birds include the penguins, ostrich, kiwi, and the extinct Dodo. Most birds are characterised by flight, though the ratites are flightless, and several other species, particularly on islands, have also lost this ability. Common characteristics of birds include a bony beak with no teeth, the laying of hard-shelled eggs, high metabolic rate, and a light but strong skeleton.

Some, such as frigatebirds, stay aloft for days at a time, even sleeping on the wing. the Wandering Albatross). Many birds migrate long distances to utilise optimum habitats (e.g., Arctic Tern) while others spend almost all their time at sea (e.g. Some birds, such as the owls and nightjars, are nocturnal or crepuscular (active during twilight hours).

Most birds are diurnal, or active during the day. Birds are a very differentiated class, with some feeding on nectar, plants, seeds, insects, rodents, fish, carrion, or other birds. Depending on taxonomic viewpoint, there are about 8,800–10,200 living bird species (plus about 120–130 that have become extinct in the span of human history) in the world, making them the most diverse class of terrestrial vertebrates. Birds range in size from the tiny hummingbirds to the huge Ostrich and Emu.

Birds are bipedal, warm-blooded, oviparous vertebrates characterized primarily by feathers, forelimbs modified as wings, and hollow bones. The recent avian flu outbreaks is named after the word avian. The Latin word for bird is avian. Tubenoses can eject an unpleasant slime against an aggressor, and some species of pitohui, found in New Guinea, secrete a powerful neurotoxin in their feathers.

Few birds use chemical defences against predators. The birds of a region are called the avifauna. To preen or groom their feathers, birds use their bills to brush away foreign particles. Second exhalation: air flows from the anterior sacs back through the trachea and out of the body.

Second inhalation: air flows from the lungs to the anterior air sacs. First exhalation: air flows from the posterior air sacs to the lungs. First inhalation: air flows through the trachea, bronchi, parabronchi (in the lung) and into the posterior air sacs. the posterior air sacs (posterior thoracics and abdominals).

the lungs, and. the anterior air sacs (interclavicular, cervicals, and anterior thoracics),. Evolution 34(5): 973-982 (1980). Zeveloff, Samuel and Boyce, Mark: Parental Investment and Mating Systems in Mammals.

Annual Review of Ecology and Systematics 25: 601-28 (1994). and Nolan, Val: Male Parental Behavior in Birds. Ketterson, Ellen D. The American Naturalist 121(2): 149-160 (1983).

Gowaty, Patricia Adair: Male Parental Care and Apparent Monogamy among Eastern Bluebirds (Sialia Sialis). Passeriformes, passerines. Coliiformes, mousebirds. Trogoniformes, trogons.

Piciformes, woodpeckers and allies. Coraciiformes, kingfishers. Trochiliformes, hummingbirds. Apodiformes, swifts.

Caprimulgiformes, nightjars and allies. Strigiformes, owls. Cuculiformes, cuckoos. Psittaciformes, parrots and allies.

Columbiformes, doves and pigeons. Pteroclidiformes, sandgrouse. Charadriiformes, plovers and allies. Gruiformes, cranes and allies.

Turniciformes, button-quail. Falconiformes, falcons. Accipitriformes, eagles, hawks and allies. Phoenicopteriformes, flamingos.

Ciconiiformes, storks and allies. Pelecaniformes, pelicans and allies. Sphenisciformes, penguins. Procellariiformes, albatrosses, petrels, and allies.

Podicipediformes, grebes. Gaviiformes, loons. Galliformes, fowl. Anseriformes, waterfowl.

Tinamiformes, tinamous. Struthioniformes, Ostrich, emus, kiwis, and allies.