Subject
photo credits: Wikimedia Commons
Birds are a group of warm-blooded vertebrates constituting the class Aves , 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 mya, 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. Source: Wikipedia (en)
Works about bird 47
-
Native Birds of Aotearoa
-
National Geographic: Field Guide to the Birds of North America (7th edition)
-
Birds of Canada (book)
-
Birds of North America (American Museum of Natural History- DK)
-
Aves de la amazonía boliviana
-
A Climatic Atlas of European Breeding Birds
-
Birds of the World: Recommended English Names
-
Know Your New Zealand Birds
-
Les Oiseaux de France
-
A field guide to birds of Armenia
-
Birds of Suriname
-
Les Oiseaux des marais
-
Fly, Little Bird
-
Masterpieces of Bird Photography
-
Nature Study Notes: 100 of the most abundant insects birds and wild flowers in New Zealand
-
New Zealand Birds and How to Identify Them
-
Against the destruction of white herons and red ibises on the lower Amazon, especially on the Island of Marajó
-
A review of recent attempts to classify birds; an address delivered before the Second international ornithological congress on the 18th of May, 1891
-
a nomenclature of colors for naturalists: and compendium of useful knowledge for ornithologists
-
A History of British Birds
-
Histoire naturelle des oiseaux de paradis et des rolliers, suivie de celle des toucans et des barbus
-
A History of British Birds
-
An Annotated Checklist of the Birds of the Oriental Region
-
Petolinnut
-
The Birds of the Sandwich Islands
-
Birds of Village and Field: a bird book for beginners
-
Extinct Birds
-
Extinct Birds of New Zealand
-
Provincial names and folk lore of British birds
-
handbook of North American birds
-
Douze oiseaux
-
Birds by Colour
Subject - wd:Q5113