Bird

Bird diseases that can be contracted by humans include psittacosis, salmonellosis, campylobacteriosis, Newcastle's disease, mycobacteriosis (avian tuberculosis), avian influenza, giardiasis, and cryptosporidiosis. The longest spans usually require suspension bridges. 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. For medium spans, trusses or box beams are usually most economical, while in some cases, the appearance of the bridge may be more important than its cost efficiency. 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. Bridges employing only compression are relatively inefficient structurally, but may be highly cost efficient where suitable materials are available near the site. Chickens and pigeons are popular as experimental subjects, and are often used in biology and comparative psychology research. For a given site, kind of bridge employed and the materials used determine the total cost, a lifetime cost composed of materials, labor, machinery, engineering, cost of money, maintenance, refurbishment, risk potential, and ultimately, demolition and associated disposal, recycling, and reuse.

Falcons are still used for hunting, while cormorants are employed by fishermen. A bridge's economic efficiency will be site and traffic dependent, the ratio of savings by having a bridge (instead of, for example, a ferry, or a longer road route) compared to its cost. For example, Homing pigeons were commonly used to carry messages before the advent of modern instant communications methods (many are still kept for sport). A more refined measure for this exercise is to weigh the completed bridge rather than measure against a fixed quantity of materials provided, a test that emphasizes economy of materials and efficient glue joints. Other birds have long been used by humans to perform tasks. The bridge taking the greatest load is by this test the most structurally efficient. In North America, introduced House Sparrows, Common Starlings, and House Finches are similarly widespread. In one common challenge young students are to be divided into groups of two or three and then to be given a fixed quantity of wood sticks, a specific distance to span, and a given glue, and then to construct a bridge that will be tested to destruction by the progressive addition of load at the center of the span.

For example, the common pigeon or Rock Dove (Columba livia) thrives in urban areas around the world. A bridge's structural efficiency may be considered to be the ratio of load carried to bridge weight, given a specific set of material types. Numerous species have come to depend on human activities for food and are widespread to the point of being pests. Bridges can also be classified by their lineage, which is shown as the vertical axis on the diagram to the 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. In other cases the forces may be distributed among a large number of members, as in a truss, or not clearly discernible to a casual observer as in a box beam. At one time swans and flamingos were delicacies of the rich and powerful, although these are generally protected now. The separation of forces may be quite clear, as in a suspension or cable-stayed span; the elements in tension are distinct in shape and placement.

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. Most bridges will employ all of the principle forces to some degree, but only a few will predominate. The most commonly eaten species is the domestic chicken and its eggs, although geese, pheasants, turkeys, and ducks are also widely eaten. Bridges may be classified by how the four forces of tension, compression, bending and shear are distributed through their structure. Birds are an important food source for humans. The central bridge was reserved exclusively for the use of the Emperor, Empress, and their attendants. This region is sometimes featherless, and the skin may be tinted (as in many species of the cormorant family). A set of five bridges cross a sinuous waterway in an important courtyard of the Forbidden City in Beijing, China.

The region between the eye and bill on the side of a bird's head is called a lore. Often in palaces a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. See bird skeleton.. Other garden bridges may cross only a dry bed of stream washed pebbles, intended only to convey an impression of a stream. Birds also have skeletons possessing unique characteristics. This type, often found in east-asian style gardens, is called a Moon bridge, evoking a rising full moon. The use of gizzard stones is a similarity between birds and dinosaurs, which left gizzard stones called gastroliths as trace fossils. To create a beautiful image, some bridges are built much taller than necessary.

For birds in captivity, only certain species of birds require grit in their diet for digestion. An aqueduct is a bridge that carries water, resembling a viaduct. 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. For example, it may be a bridge carrying a highway and forbidden for pedestrians and bicycles, or a pedestrian bridge, possibly also for bicycles. 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. In some cases there may be restrictions in use. The active phase of respiration in birds is exhalation, requiring effort of the musculature. A bridge is usually designed for trains, pedestrian or road traffic, a pipeline or waterway for water transport or barge traffic.

A diaphram is absent in birds; the entire body cavity acts as a bellows to move air through the lungs. There are four main types of bridges: beam bridges, cantilever bridges, arch bridges and suspension bridges. 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 Oxford English Dictionary traces the origin of the word bridge to an Old Norse word bryggja, meaning "landing stage, gangway, or movable pier". 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. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel. 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. With the rise of the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron did not have the tensile strength to support large loads.

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. The first engineering book on building bridges was written by Hubert Gautier in 1716. Air flows through the air sacs and lungs as follows:. During the 18th century there were many innovations in the design of timber bridges by Hans Ulrich, Johannes Grubenmann, and others. It takes a bird two full breaths to completely cycle the air from each inhalation through its lungs and out again. Rope bridges, a simple type of suspension bridge, were used by the Inca civilization in the Andes mountains of South America, just prior to European colonization in the 1500s. There are three distinct sets of organs involved in respiration:. Brick and mortar bridges were built after the Roman era, as the technology for cement was lost then later rediscovered.

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. The Romans also had cement, which reduced the variation of strength found in natural stone. 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 arch was first used by the Roman Empire for bridges and aqueducts, some of which still stand today. 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. The first bridges were spans made of wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. "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 extreme loss of mating opportunities leads to a reduction in reproductive success among incubating males. The purpose of a bridge is to allow easier passage by providing a continuous more uniform more easily navigable route via what would otherwise be an uneven or impossible path for the particular kind of thing travelling or being transported, whether people, vehicles, trains, ships, liquids or whatever else. It takes time and also may require physiological changes that interfere with continued mating. Designs may be built higher than otherwise needed in order to allow other traffic (particularly ship traffic) beneath. Interestingly, male incubation is the most confining male parental behavior. A bridge is a structure built to span a gorge, valley, road, railroad track, river, body of water, or any other physical obstacle. The parental behavior most closely associated with monogamy is male incubation. Pearl Harbor Memorial Bridge - USA, will be the first extradosed cable-stayed bridge constructed in the United States.

"In one form of monogamy such as with obligate monogamy a female cannot rear a litter without the aid of a male" (Gowaty, 1983). Zakim Bunker Hill Bridge - USA, built during Boston's Big Dig, the widest cable-stayed bridge. In birds, male care can be seen as important or essential to female fitness. Victoria Falls Bridge - linking Zimbabwe to Zambia, built in 1905 as part of the projected Cape-Cairo railway. 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. Vasco da Gama Bridge - Portugal, the longest bridge in Europe at 17.2 km. 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. Trajan's bridge - Romania, ancient Roman bridge over the river Danube, only fragments visible.

In some cases, the individuals may pair for life. Tyne Bridge - England, one of Northern England's most iconic structures. Monogamous species of males and females pair for the breeding season. Tsing Ma Bridge - Hong Kong, the world's longest rail & road suspension bridge. Polygyny constitutes 2% of all birds and polyandry is seen in less than 1%. Tower Bridge - London, England, and a symbol of this city. Monogamy is seen in approximately 91% of all bird species. Tatara Bridge - Japan, largest span cable-stayed bridge.

The three mating systems that predominate among birds are polyandry, polygyny, and monogamy. Tacoma Narrows Bridge - USA, famous for its collapse due to aerodynamic effects. Sources for this section include:. Sydney Harbour Bridge - Australia, arguably the best-known suspended-deck compression arch bridge. 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. Sundial Bridge - USA, a dramatic single cantilever spar cable stayed span for pedestrians. The process whereby a chick acquires feathers until it can fly is called "fledging". San Francisco-Oakland Bay Bridge - USA, especially for seismic retrofit and eastern span replacement.

The young of hole-nesters, on the other hand, are often totally incapable of unassisted survival. Québec Bridge - Canada, largest cantilever bridge in the world. 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. Penang Bridge - Malaysia, longest bridge in Southeast Asia. Precocial birds can care for themselves independently within minutes of hatching; altricial hatchlings are helpless, blind, and naked, and require extended parental care. Palace Bridge - St Petersburg, Russia, one of iconic images of the city. After the eggs hatch, parent birds provide varying degrees of care in terms of food and protection. Overtoun Bridge, - Scotland, dogs have leaped to their deaths from this bridge, leading to urban legends.

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. Øresundbroen/Öresundsbron. Except during copulation, it is hidden within the proctodeum compartment within the cloaca, just inside the vent. Millau Viaduct - France, tallest bridge in the world. Many waterfowl and some other birds, such as the ostrich and turkey, do possess a phallus. Menai Suspension Bridge - Wales, first road suspension bridge in the world. The eggs will then continue their development in the nest. Mahatma Gandhi Setu - India, the longest river bridge in the world.

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. Mackinac Bridge - USA, Opened to traffic in 1957, connecting the two peninsulas of Michigan; held the title of the world's longest two tower suspension bridge between anchorages until the 1990s. The sperm is stored in the female's cloaca for anywhere from a week to a year, depending on the species of bird. Lupu Bridge- China, longest single steel arch. This can happen very fast, sometimes in less than one second. Lake Pontchartrain Causeway - USA, spanning Lake Pontchartrain in south Louisiana, it is the longest bridge in the world at 23.87 miles (38.41 km). 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. Jamuna Bridge- Bangladesh, longest rail-road bridge in south asia , 2nd longest in world.

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. Confederation Bridge - Canada, world's longest bridge over waters that freeze. In the males of species without a phallus (see below), sperm is stored within the proctodeum compartment within the cloaca prior to copulation. The Iron Bridge - England, the world's first iron bridge. The female's ovaries also become larger, although only the left ovary actually functions. Golden Gate Bridge - USA, arguably the most beautiful of its type. 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. Forth Railway Bridge - Scotland, one of the most famous cantilever bridges in the world.

See also: Sibley-Ahlquist taxonomy. Akashi-Kaikyo Bridge - Japan, with the longest section span of 1.9 km. 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.