What Class Of Animal Is A Bird?

?

Birds

Great Tit, Parus major

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Aves Linnaeus, 1758

Orders

Many - see section beneath.

Birds (class Aves) are bipedal, warm-blooded, oviparous (egg-laying) vertebrates characterized primarily by feathers, forelimbs modified equally wings, and a bony beak without teeth. Common characteristics of birds include the laying of hard-shelled eggs, high metabolic rate, and a lite but potent skeleton, mostly with hollow bones.

The only animals covered with feathers, virtually birds are characterized by flying. Many birds migrate long distances to utilize optimum habitats (e.g., Arctic tern), while others spend about all their time at sea (eastward.grand., the wandering albatross). Some, such equally frigatebirds, stay aloft for days at a time, even sleeping on the wing. The fastest living animate being is a bird, the peregrine falcon (Falco peregrinus), which has been observed to achieve a flight speed of at least 124 mph (200 km/h) and perhaps 350 km/h (217 mph) during a dive. On the other hand, the ratites are flightless, and several other species, particularly on islands, have also lost this power. Flightless birds include the penguin, ostrich, kiwi, and the extinct dullard.

Birds range in size from the tiny hummingbirds to the huge ostrich and emu. Depending on taxonomic viewpoint, there are nigh eight,800 to x,200 living bird species in the world, making them the nearly diverse class of terrestrial vertebrates.

The path of humans and birds take intersected in many means throughout homo civilisation, whether direct through hunting and domestication, or as powerful symbols in literature, arts, and organized religion. The dove has been used as a symbol of peace and love, as well as the Holy Spirit in Christianity; cranes have symbolized long life, and owls wisdom. The bulk of birds are monogamous and many species mate for life, reflecting the higher aspirations of the human spirit and faith.

Birds are a very differentiated class, with some feeding on nectar, plants, seeds, insects, rodents, fish, carrion, or other birds. Some birds even feed on parasites on blackness rhinoceroses, or within the mouths of crocodiles. About birds are diurnal, or agile during the twenty-four hours. Some birds, such as the owls and nightjars, are nocturnal or crepuscular (active during twilight hours). Many birds seasonally migrate long distances, improving opportunities for food, better climate, and breeding.

i Bird classification
- one.ane Bird orders
- one.2 Species and habitats
two Beefcake and physiology
- 2.1 Feathers
- 2.two Skeleton
- 2.3 Digestive system
- 2.4 Respiration
- ii.5 Circulatory, nervous and metabolic systems
- two.half dozen Reproduction
3 Mating systems and parental care
4 Birds and humans
- 4.ane Birds every bit nutrient and products
- 4.2 Birds as pets and to perform tasks
- four.iii Birds in art, literature, and faith
- 4.iv Human-caused declines in birds
5 Evolution
half-dozen References
7 Credits

Birds are amidst the virtually extensively studied of all brute groups. Hundreds of academic journals and thousands of scientists are devoted to bird enquiry, while amateur enthusiasts (called birdwatchers or birders) probably number in the millions.

Bird nomenclature

Birds form a class, whose scientific name is Aves. Modernistic birds are classified in the subclass Neornithes, which is further separated into ii superorders, the Paleognathae (generally flightless birds), and the wildly diverse Neognathae, containing all other birds. At that place is besides an extinct subclass, Archaeornithes.

The paleognaths include the tinamous (constitute only in Key and South America) and the ratites. The ratites are large flightless birds, and include ostriches, cassowaries, kiwis, and emus. Some scientists doubtable that the ratites represent an artificial grouping of birds which accept independently lost the power to fly, while others contend that the ratites never had the power to fly and are more than directly related to the dinosaurs than other modernistic birds.

The classification of birds is a contentious issue. Sibley and Ahlquist'south Phylogeny and Nomenclature of Birds (1990) is an often cited work on the nomenclature of birds, but is besides frequently debated and constantly revised. Evidence has been accumulated that the modernistic bird orders constitute accurate taxa. However, scientists are not in agreement as to the relationships between the orders; evidence from modern bird beefcake, fossils and Dna take all been brought to bear on the problem just no strong consensus has emerged. Some postulated the Galloanseri (see nautical chart) as the basal divergence from the remaining Neognathes. The Galloanseri incorporate the Anseriformes (ducks, geese and swans), and the Galliformes (the pheasants, bickering, and their allies). While there is full general consensus that the orders Anseriformes and Galliformes represent sister-groups, there remain opposing points of view.

Bird orders

Relationships between bird orders

This is a list of the taxonomic orders in the course Aves. The listing of birds gives a more detailed summary, including families.

Struthioniformes, Ostrich, emus, kiwis, and allies
Tinamiformes, tinamous
Anseriformes, waterfowl
Galliformes, fowl
Sphenisciformes, penguins
Gaviiformes, loons
Podicipediformes, grebes
Procellariiformes, albatrosses, petrels, and allies
Pelecaniformes, pelicans and allies
Ciconiiformes, storks and allies
Phoenicopteriformes, flamingos
Accipitriformes, eagles, hawks and allies
Falconiformes, falcons
Turniciformes, push-quail
Gruiformes, cranes and allies
Charadriiformes, plovers and allies
Pteroclidiformes, sandgrouse
Columbiformes, doves and pigeons
Psittaciformes, parrots and allies
Cuculiformes, cuckoos
Strigiformes, owls
Caprimulgiformes, nightjars and allies
Apodiformes, swifts
Trochiliformes, hummingbirds
Coraciiformes, kingfishers
Piciformes, woodpeckers and allies
Trogoniformes, trogons
Coliiformes, mousebirds
Passeriformes, passerines

Note: This is the traditional classification (the so-called Clements order). A more recent, essentially dissimilar nomenclature based on molecular data has been developed (the then-called Sibley order) and is gaining acceptance.

Species and habitats

The estimated number of living bird species is often put around ten k, but ranges from eight,800–10,200. This compares to well-nigh 4,800 species of mammals and 7,150 species of reptiles.

Birds accept adapted to near every office of the globe and a wide diversity of habitats: forests, grasslands, cities, mountains, deserts, wetlands, and oceans. Fifty-fifty the snowy owl (Bubo scandiacus) is adapted to live north of the Arctic Circle, where the temperature can be below -46°C during the winter, and penguins thrive in the Antarctica. The albatrosses spend much of their time soaring over the open ocean, and the emperor penguin (Aptenodytes forsterican) plunges to depths of more than 250 meters (850 feet) searching for food.

However, birds have by and large been adapted to terrestrial land—only 2 pct of all birds are aquatic. Most of these, about 150 species, are duck like birds, as well every bit a small number of grebes (20), loons (4), penguins (xv), and auks (21) (Mayr 2001). Additionally, only a few birds are leaf-eaters, with a notable one beingness the hoatzin (Ophisthocomus hoazin).

Beefcake and physiology

Beefcake of a typical bird

Feathers

A distinguishing characteristic of birds is feathers. Other animals have wings and can fly, such as bats, but only birds are covered with feathers.

Feathers are among the nearly complex structural organs found in vertebrates. These integumentary appendages are formed by controlled proliferation of cells in the epidermis (outer skin layer) from a protein called keratin. These fibrous structural proteins form the difficult, just non-mineralized structures constitute in bird feathers, beaks, and claws, also as reptilian claws, shells, and scales, and mammalian hair (including wool), nails, claws, horns, and hooves of mammals. The β-keratins used by birds and reptiles are even tougher than the α-keratins of mammals.

Feathers insulate birds from water and cold temperatures. Individual feathers in the wings and tail play of import roles in controlling flying. Color patterns serve as cover-up against predators for birds in their habitats, and by predators looking for a meal. Striking differences in feather patterns and colors are role of the sexual dimorphism of many bird species and are particularly important in choice of mating pairs. The blue and green colors in most parrots are attributed to a texture outcome in microscopic portions of the feather itself, rather than pigment.

parts of a contour feather

Skeleton

Birds also have skeletons possessing unique characteristics.

The avian (bird) skeleton is highly adapted to these animals' chapters for flight. It is extremely lightweight, just strong enough to withstand the stresses that a bird experiences when taking off, flying and landing. 1 of the adaptations that make this possible is the fusing of bones that are separate in mammals into single ossifications. Because of this, birds usually have a smaller number of bones than mammals or reptiles, and the frame has more forcefulness.

Birds have many bones that are hollow, with criss-crossing struts or trusses (cross walls) for structural strength. (Some flightless birds similar penguins have just solid bones, nevertheless). The number of hollow basic varies from species to species, though large gliding and soaring birds tend to accept the most.

Birds besides have more than cervical (neck) vertebrae than many other animals; nigh take a highly flexible neck that consists of 13-25 vertebrae. Although the neck is flexible, near of the skeleton is rather stiff. Birds are the only vertebrate animals to have a fused collarbone (the furcula or wishbone) or a keeled breastbone (or sternum). The heaviest and strongest bone is the coracoid.

Although feathers are calorie-free, a bird's feather weighs 2 or three times more than its skeleton, since many bones are hollow and contain air sacks. The lack of teeth also lightens the frame.

The pectoral (breast) muscles of birds are the largest, and may account for 20% of a bird's weight.

Digestive system

A bird'south digestive system extends from the rima oris, through the pharynx, into the esophagus, into the breadbasket, through the modest intestine and the large intestine, and out the cloacal opening. Some birds accept a crop, which is a storage pouch that is part of the esophagus and tin allow birds to feed and store food until later digestion. About birds accept a breadbasket fabricated of two parts, the first part, or proventriculus, which secretes digestive fluids, and the 2nd, the gizzard.

Defective teeth, birds use their digestive organisation to grind and pulverize food. The ventriculus or gizzard is equanimous of four muscular bands that act to rotate and crush food past shifting the food from ane surface area to the next within the gizzard. Depending on the species, the gizzard may contain minor pieces of grit or stone that the bird has swallowed to aid in the grinding process of digestion. For birds in captivity, simply certain species of birds crave grit in their diet for digestion. The apply of gizzard stones appears to be a similarity betwixt birds and dinosaurs, based on trace fossils of gizzard stones called gastroliths.

Respiration

The loftier metabolism of birds necessitates an effective system for acquiring a great deal of oxygen.

Birds ventilate their lungs by ways of crosscurrent flow: the air flows at a 90° angle to the flow of blood in the lungs' capillaries. In addition to the lungs themselves, birds have posterior and inductive air sacs (typically nine), which control airflow through the lungs, merely exercise not play a straight role in gas exchange. There are three distinct sets of organs involved in respiration:

the anterior air sacs (interclavicular, cervicals, and anterior thoracics),
the lungs, and
the posterior air sacs (posterior thoracics and abdominals).

Information technology takes bird 2 full breaths to completely cycle the air from each inhalation through its lungs and out again. Air flows through the air sacs and lungs as follows:

First inhalation: air flows through the trachea and bronchi into the posterior air sacs.
Showtime exhalation: air flows from the posterior air sacs to the lungs.
2nd inhalation: air flows from the lungs to the anterior air sacs.
2nd exhalation: air flows from the anterior sacs dorsum through the trachea and out of the trunk.

Since during inhalation and exhalation fresh air flows through the lungs in only ane direction, at that place is no mixing of oxygen rich air and carbon dioxide rich air within the lungs every bit in mammals. Thus the partial pressure of oxygen in a bird's lungs is the same every bit the environment, then birds have more than efficient gas-exchange of both oxygen and carbon dioxide than do mammals.

Avian lungs do not have alveoli, every bit mammalian lungs do, but instead contain millions of tiny passages known as parabronchi, connected at either ends by the dorsobronchi and ventrobronchi. Air flows through the honeycombed walls of the parabronchi and into air capillaries, where oxygen and carbon dioxide are traded with cross-flowing claret capillaries by diffusion.

Circulatory, nervous and metabolic systems

Birds have four-chambered hearts, and a circulatory system with blood vessels. Birds' high metabolism requires rapid circulation because of the quick build upwards of waste products, and need for oxygen.

In full general, birds generally have exceptional vision, well-adult hearing, and a poor sense of odour. As a group, their vision is the best of all animals. Large eyes, often heavier than their brain, offering stiff visual vigil and colour perception. However, Kiwi, flightless, nocturnal birds endemic (native) to New Zealand, are nearly blind. They rely on a highly developed sense of odor, with nostrils at the end of their long bill. Well-nigh birds do non have a good sense of smell. Hearing is generally well adult. For example, even without light, or any visual cues, befouled owls tin can track their casualty by audio.

Birds are both endothermic (create their ain heat) and homeothermic (maintain a constant internal temperature). They also generally maintain a higher body temperature than mammals, with a temperature more often than not between 40 and 44°C. Virtually eighty percent of bird species maintain higher temperature than all but ten% of mammal species.

Birds as well by and large have a faster heart rate and a greater need for oxygen than mammals, and have a higher metabolic rate. Smaller birds mostly have a higher metabolism than larger birds, and have relatively college energy needs. A hummingbird must feed almost constantly during the day, whereas an emperor penguin goes more than than ii months without feeding while incubating the couple's egg.

Reproduction

Infant bird unable to fly yet

Although most male person birds have no external sex organs, the male does have two testes which go hundreds of times larger during the breeding season to produce sperm. The female'due south ovaries as well become larger, although only the left ovary actually functions.

In the males of species without a phallus (see below), sperm is stored within the proctodeum compartment within the cloaca prior to copulation. 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. He moves the opening of his cloaca, or vent, close to hers, so that the sperm can enter the female'south cloaca, in what is referred to every bit a cloacal buss. This can happen very fast, sometimes in less than 1 second.

A juvenile Laughing Gull.

The sperm is stored in the female's cloaca for anywhere from a calendar week to a year, depending on the species of bird. So, one by one, eggs will descend from the female'southward ovaries and go fertilized by the male's sperm, before being afterwards laid by the female. The eggs volition and then continue their development in the nest.

Many waterfowl and another birds, such every bit the ostrich and turkey, practice possess a phallus. Except during copulation, it is subconscious within the proctodeum compartment within the cloaca, just inside the vent. The avian phallus is purely a copulatory organ and is non used for expelling urine.

After the eggs hatch, parent birds provide varying degrees of care in terms of food and protection. Precocial birds—those that are relatively mature at nascence—tin care for themselves independently within minutes of hatching. Altricial hatchlings—those built-in helpless—are blind and naked, and require extended parental care. The chicks of many basis-nesting birds, such equally partridges, chickens, and waders, are oft able to run almost immediately after hatching; such birds are referred to as nidifugous. The young of hole-nesters, on the other hand, are often totally incapable of unassisted survival. The process whereby a chick acquires feathers until it can fly is chosen "fledging."

Mating systems and parental care

(Clockwise from top left) The jabiru (Jabiru mycteria), the greenish-and-red macaw, or green-winged macaw (Ara chloroptera), the bald eagle (Haliaeetus leucocephalus), and the albatross (family Diomedeidae) are examples of birds that mate for life.

The three mating systems that predominate among birds are polyandry, polygyny, and monogamy. Monogamy (having one partner for reproduction and raising the young) is seen in approximately 91% of all bird species. Polygyny (one male with more than ane female) constitutes 2% of all birds, and polyandry (one female person with more than 1 male) is seen in less than ane%.

Monogamous species of males and females pair for the breeding season. In some cases, the individuals may pair for life. For example, the albatross, bald eagle, and Canadian goose, equally well equally species of macaws, owls, and crows, mate for life. When the mate dies, there is often a re-mating of the surviving bird. There are instances of one bird showing signs of distress upon the decease of a mate, although when the mate is removed from the sight of the survivor, this behavior subsides.

One explanation for the high rate of monogamy among birds is the fact that male person birds are only every bit proficient at parental care as females. In almost groups of animals, male person parental care is rare, but in birds it is quite common; in fact, information technology is more extensive in birds than in any other vertebrate class. In birds, male care tin can be seen as of import or essential to female fitness. "In i form of monogamy, such as with obligate monogamy, a female cannot rear a litter without the aid of a male" (Gowaty 1983).

The parental behavior most closely associated with monogamy is male incubation. Interestingly, male incubation is the most confining male parental beliefs. It takes fourth dimension and too may require physiological changes that interfere with connected mating. For case, in the case of the emperor penguin, after the female penguin lays its egg, she returns to the sea to feed for two months to replenish her nutritional reserves. During this fourth dimension, the male incubates the egg in its brood pouch for about 2 months consecutively without nutrient. If the chick hatches before the mother's return, the begetter feeds it a substance produced by a gland in his esophagus.

These redwing hatchlings are completely dependent on parental intendance.

Monogamy does not necessarily translate to fidelity among the pairs, as examples to the opposite are known. Information technology is certainly problematic to compare mating habits of species in cosmos with man habits, given that people are endowed with a spiritual as well as physical nature. (Run into human and human body.) Nevertheless, the dominance of monogamy in birds, and the all-encompassing phenomena of pairing for life equally a universal standard inside certain bird species, provides a counterbalance to the current social Darwinistic views of some that monogamy, pairing for life, and fidelity in humans is an unnatural country. (Run into reproduction for an elaboration of this perspective.)

Birds and humans

Birdbox is an artificial platform for birds to make a nest

Throughout the ages, birds have been integral to human civilization, whether every bit nutrient, pets, bird products, or inspiration for paintings, literature, and organized religion. Unfortunately, hunting, destruction of habitat, and pollution have also caused many birds to be placed on lists as endangered or threatened species. At that place are also an estimated (plus about 120–130 that have go extinct in the span of human history.

Birds as food and products

Birds are an of import food source for humans. The most commonly eaten species is the domestic chicken and its eggs, although geese, pheasants, turkeys, and ducks are likewise widely eaten. Other birds that accept been utilized for nutrient include emus, ostriches, pigeons, grouse, quails, doves, woodcocks, songbirds, and others, including small passerines, such as finches. At ane time swans and flamingos were delicacies of the rich and powerful, although these are generally protected now.

Birds take served as a food source since prehistoric times. Eventually, people were able to domesticate birds, including chickens, ducks, and turkeys.

Birds have too provided products for utilize in man societies, such as feathers and skins. Feathers have been used for pillows and for article of clothing, and skins for warm, waterproof clothing and blankets.

Numerous species also have come to depend on homo activities for food and are widespread to the betoken of being pests. For instance, the common dove or Rock Dove (Columba livia) thrives in urban areas effectually the earth. In Northward America, introduced House Sparrows, Common Starlings, and House Finches are similarly widespread.

Birds as pets and to perform tasks

Humans accept long used birds to perform various tasks. For example, Homing pigeons were commonly used to acquit messages before the appearance of modern instant communications methods (many are still kept for sport). Falcons are withal used for hunting, while cormorants are employed past fishermen.

Chickens and pigeons are popular equally experimental subjects, and are frequently used in biology and comparative psychology research. Every bit 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.

Colorful, specially tropical, birds (east.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.

Bird diseases that can be contracted by humans include psittacosis, salmonellosis, campylobacteriosis, Newcastle's illness, mycobacteriosis (avian tuberculosis), avian flu, giardiasis, and cryptosporidiosis.

Birds in fine art, literature, and faith

Birds take been prominent in human civilisation since the earliest days, every bit evidenced past their appearance on religious cave paintings (as in the Lascaux Cave in France) and their depiction in ancient Egyptian art, adorning sculptures and tombs of royalty. Egyptians likewise included birds among their gods, and the ibis was ofttimes mummified and placed in the tombs with royalty.

Birds are as well prominent in the Bible, with over forty species of birds mentioned. In the book of Job (39:26-27), there are references to migrating birds: "Is information technology by your wisdom that the hawk soars and spreads his wings toward the south?" and the ways of eagles: "Is it at your command that the eagle mounts up and makes his nest on high?" Likewise, in Jeremiah (8:7) migration is also noted: "Fifty-fifty the stork in the heavens knows her times; and the turtledove, swallow, and crane keep the time of their coming." In Chapter 15 of Genesis, Abraham is depicted every bit making an offer to the Lord that included a turtledove and a young pigeon, and subsequently birds of prey are depicted as coming down on the offer. And it was a raven, and later a dove, that Noah sent along from the Arc to run into if the waters had subsided.

Birds accept also been depicted equally powerful symbols in human culture. The dove is used every bit symbol of peace (with an olive branch) and the Holy Spirit in Christianity. Crows, and especially ravens, which are considered to exist of loftier intelligence relative to many other birds, are frequently considered in legends or mythology as portents or harbingers of doom or death, because of their dark color or scavenger habits. The bald eagle is a symbol of the United States, and cranes accept been used in the East as representative of long life.

Human-caused declines in birds

Many species take become extinct through over-hunting, such as the Passenger Pigeon, and many others take become endangered or extinct through habitat devastation, deforestation and intensive agriculture.

The rider pigeon was mayhap the well-nigh common bird in the world, with an estimated 5 billion in the United States. They lived in massive flocks, with one flock estimated at two billion birds and taking several days to pass overhead. Simply rider pigeons likewise were very pop for food and hog feed, and were shot in mass numbers by commercial hunters. By 1900, the last wild passenger dove was killed.

As well, the Great Auk, flightless rails, and the moa of New Zealand, for example, all became extinct due to human influence. The flightless dodo became extinct in the 17th century, largely because of animals brought by people that damaged the dullard's nests, also as habitat devastation.

Many parrots are endangered because of poaching for the pet trade, and habitat destruction, both past humans and by animals introduced by humans.

Development

There are two major conjectures regarding the origin of birds (Mayr 2001). Ane, the thecodont theory, is that birds arose from archosaurian reptiles former before the Upper Jurassic (around 135 to 160 million years agone), perhaps in the late Triassic more than than 200 million years agone. The other scenario is that birds evolved from theropod dinosaurs. This later on dinosaurian theory, which is quite popular, is supported past the remarkable similarity between birds and bipedal dinosaurs of the later on Cretaceous, around 70 to 100 million years ago. (See geologic fourth dimension calibration.)

The oldest known fossil bird Archaeopteryx, from the Upper Jurassic, is considered as one of the first "missing links" to be plant in support of evolution, afterwards the first fossil specimens were found in the tardily nineteenth century. However, it also presents a complication for the dinosaurian theory. Archaeopteryx lived some 145 million years agone. Eminent evolutionist Ernst Mayr (2001) notes that this species has so many avant-garde avian characters that the original birds much have existed considerably before. Still, at that place have non been any birdlike dinosaurs known from the Jurassic or earlier periods. The almost birdlike dinosaurs occurred in the Cretaceous period, well after Archeopteryx disappeared. There are other complications that Mayr lists, including that the digits in the hands of dinosaurs are 2, iii and four, while they are one, two, and three in birds, and that it is inconceivable how the extremities of birdlike dinosaurs could have been shifted to flight, being reduced and not pre-adjusted to become wings.

The recently discovered dromaeosaur, Cryptovolans, appears capable of powered flying, independent a keel and had ribs with uncinate processes. In fact, some consider that Cryptovolans makes a better "bird" than Archaeopteryx, which is missing some of these modern bird features. Considering of this, some paleontologists have suggested that dromaeosaurs are really basal birds whose larger members are secondarily flightless, i.due east. dromaeosaurs evolved from birds and not the other manner effectually. Show for this theory is currently inconclusive, but digs go on to unearth fossils (especially in Mainland china) of the strange-feathered dromaeosaurs.

Information technology should exist noted that although ornithischian (bird-hipped) dinosaurs share the same hip structure every bit birds, birds are actually considered by many paleontologists to have originated from the saurischian (lizard-hipped) dinosaurs, and thus arrived at their hip structure condition independently. In fact, the bird-like hip structure also is speculated to accept adult a third fourth dimension amidst a peculiar group of theropods, the Therizinosauridae.

References
ISBN links support NWE through referral fees

Gowaty, P. A. 1983. Male parental care and credible monogamy among Eastern Bluebirds (Sialia sialis). The American Naturalist 121(2):149-160.
Ketterson, E. D., and 5. Nolan. 1994. Male person parental beliefs in birds. Annual Review of Ecology and Systematics 25:601-28.
Mayr, E. 2001. What Development Is. New York, NY: Basic Books.
Zeveloff, S., and One thousand. Boyce. 1980. Parental investment and mating systems in mammals. Evolution 34(5):973-982.

Credits

New Earth Encyclopedia writers and editors rewrote and completed the Wikipedia article in accord with New Earth Encyclopedia standards. This article abides past terms of the Artistic Commons CC-past-sa iii.0 License (CC-past-sa), which may be used and disseminated with proper attribution. Credit is due nether the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this commodity click hither for a list of acceptable citing formats.The history of before contributions past wikipedians is attainable to researchers hither:

Bird ^history
Plumage ^history
Bird_skeleton ^history

The history of this article since it was imported to New Earth Encyclopedia:

History of "Bird"

Note: Some restrictions may employ to use of individual images which are separately licensed.

What Class Of Animal Is A Bird?

Contents