Portal:Birds - Biblioteka.sk

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Portal:Birds
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The Birds Portal

Birds are a group of warm-blooded vertebrates constituting the class Aves (/ˈvz/), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the 5.5 cm (2.2 in) bee hummingbird to the 2.8 m (9 ft 2 in) common ostrich. There are over 11,000 living species, more than half of which are passerine, or "perching" birds. Birds have wings whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the loss of flight in some birds, including ratites, penguins, and diverse endemic island species. The digestive and respiratory systems of birds are also uniquely adapted for flight. Some bird species of aquatic environments, particularly seabirds and some waterbirds, have further evolved for swimming. The study of birds is called ornithology.

Birds are feathered theropod dinosaurs and constitute the only known living dinosaurs. Likewise, birds are considered reptiles in the modern cladistic sense of the term, and their closest living relatives are the crocodilians. Birds are descendants of the primitive avialans (whose members include Archaeopteryx) which first appeared during the Late Jurassic. According to recent estimates, modern birds (Neornithes) evolved in the Late Cretaceous and diversified dramatically around the time of the Cretaceous–Paleogene extinction event 66 million years ago, which killed off the pterosaurs and all non-avian dinosaurs.

Many social species pass on knowledge across generations, which is considered a form of culture. Birds are social, communicating with visual signals, calls, and songs, and participating in such behaviours as cooperative breeding and hunting, flocking, and mobbing of predators. The vast majority of bird species are socially (but not necessarily sexually) monogamous, usually for one breeding season at a time, sometimes for years, and rarely for life. Other species have breeding systems that are polygynous (one male with many females) or, rarely, polyandrous (one female with many males). Birds produce offspring by laying eggs which are fertilised through sexual reproduction. They are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching.

Many species of birds are economically important as food for human consumption and raw material in manufacturing, with domesticated and undomesticated birds being important sources of eggs, meat, and feathers. Songbirds, parrots, and other species are popular as pets. Guano (bird excrement) is harvested for use as a fertiliser. Birds figure throughout human culture. About 120 to 130 species have become extinct due to human activity since the 17th century, and hundreds more before then. Human activity threatens about 1,200 bird species with extinction, though efforts are underway to protect them. Recreational birdwatching is an important part of the ecotourism industry. (Full article...)

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Selected general bird topic

Hybrid turaco

A bird hybrid is a bird that has two different species as parents. The resulting bird can present with any combination of characteristics from the parent species, from totally identical to completely different. Usually, the bird hybrid shows intermediate characteristics between the two species. A "successful" hybrid is one demonstrated to produce fertile offspring. According to the most recent estimates, about 16% of all wild bird species have been known to hybridize with one another; this number increases to 22% when captive hybrids are taken into account. Several bird species hybridize with multiple other species. For example, the mallard (Anas platyrhynchos) is known to interbreed with at least 40 different species. The ecological and evolutionary consequences of multispecies hybridization remain to be determined.

In the wild, some of the most frequently reported hybrids are waterfowl, gulls, hummingbirds, and birds-of-paradise. Mallards, whether of wild or domestic origin, hybridize with other ducks so often that multiple duck species are at risk of extinction because of it. In gulls, Western × Glaucous-winged Gulls (known as "Olympic Gulls") are particularly common; these hybrids are fertile and may be more evolutionarily fit than either parent species. At least twenty different hummingbird hybrid combinations have been reported, and intergeneric hybrids are not uncommon within the family. (Full article...)
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Selected taxon

Sandhill cranes
(Antigone canadensis)

Cranes are a type of large bird with long legs and necks in the biological family Gruidae of the order Gruiformes. The family has 15 species placed in four genera which are Antigone, Balearica, Leucogeranus, and Grus. They are large birds with long necks and legs, a tapering form, and long secondary feathers on the wing that project over the tail. Most species have muted gray or white plumages, marked with black, and red bare patches on the face, but the crowned cranes of the genus Balearica have vibrantly-coloured wings and golden "crowns" of feathers. Cranes fly with their necks extended outwards instead of bent into an S-shape and their long legs outstretched.

Cranes live on most continents, with the exception of Antarctica and South America. Some species and populations of cranes migrate over long distances; others do not migrate at all. Cranes are solitary during the breeding season, occurring in pairs, but during the nonbreeding season, most species are gregarious, forming large flocks where their numbers are sufficient.

They are opportunistic feeders that change their diets according to the season and their own nutrient requirements. They eat a range of items from small rodents, eggs of birds, fish, amphibians, and insects to grain and berries. Cranes construct platform nests in shallow water, and typically lay a clutch of two eggs at a time. Both parents help to rear the young, which remain with them until the next breeding season. Most species of cranes have been affected by human activities and are at the least classified as threatened, if not critically endangered. The plight of the whooping cranes of North America inspired some of the first US legislation to protect endangered species. (Full article...)
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Topics

Quotes

--Joseph Addison, The Spectator [1], 1712

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Resources

Free online resources:

There is also Birds of North America, Cornell University's massive project collecting information on every breeding bird in the ABA area. It is available for US$40 a year.

For more sources, including printed sources, see WikiProject Birds.

WikiProjects

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Selected bird anatomy topic

The M. protractor pterygoidei et quadrati is a cranial muscle that pulls the streptostylic quadrate dorsorostrally in birds. (Full article...)
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Selected species

Male and female superb fairy-wrens
The superb fairy-wren (Malurus cyaneus), also known as superb blue-wren or colloquially as blue wren, is a passerine bird of the family Maluridae. Sedentary and territorial, it is found across southeastern Australia. The male in breeding plumage has a striking bright blue forehead, ear coverts, mantle and tail with a black mask and black or dark blue throat. Non-breeding males, females and juveniles are predominantly grey-brown in colour. Two subspecies are recognised. Like other fairy-wrens, the superb fairy-wren is notable for several peculiar behavioural characteristics; birds are socially monogamous and sexually promiscuous. Male wrens pluck yellow petals and display them to females as part of a courtship display. The superb fairy-wren can be found in almost any area that has at least a little dense undergrowth for shelter. It has adapted well to the urban environment. The superb fairy-wren mainly eats insects and supplements its diet with seeds.


Did you know

  • ...that sexual size dimorphism in the brown songlark is among the most pronounced in any bird, with males as much as 2.3 times heavier than females?
  • ...that rufous whistler birds, unlike all other whistler birds, never forage on the ground but high up in trees or other high places?
  • ...that the bill of the magpie duck (pictured) becomes green as the bird gets older, and its black crown may go completely white?

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Create requested articles (WikiProject Birds – Article requests):

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More outstanding tasks at the project's cleanup listing, Category:Birds articles needing attention, and Wikipedia:WikiProject Birds/Todo.

Taxonomy of Aves

Associated Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

Sources

  1. ^ Thompson, C. (2017). The Art of Mindful Birdwatching: Reflections on Freedom & Being. Mindfulness Series. Ivy Press. p. 28. ISBN 978-1-78240-428-6. Retrieved February 7, 2020.
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