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Bird
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Birds (class Aves) are winged, bipedal, endothermic (warm-blooded), vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the 5 cm (2 in) Bee Hummingbird to the 2.7 m (8 ft 10 in) Ostrich. The fossil record indicates that birds evolved from theropod dinosaurs during the Jurassic period, around 150–200 Ma (million years ago), and the earliest known bird is the Late Jurassic Archaeopteryx, c 155–150 Ma. Most paleontologists regard birds as the only clade of dinosaurs that survived the Cretaceous–Tertiary extinction event approximately 65.5 Ma.
Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. All birds have forelimbs modified as wings and most can fly, with some exceptions including ratites, penguins, and a number of diverse endemic island species. Birds also have unique digestive and respiratory systems that are highly adapted for flight. Some birds, especially corvids and parrots, are among the most intelligent animal species; a number of bird species have been observed manufacturing and using tools, and many social species exhibit cultural transmission of knowledge across generations.
Many species undertake long distance annual migrations, and many more perform shorter irregular movements. Birds are social; they communicate using visual signals and through calls and songs, and participate in social behaviours including cooperative breeding and hunting, flocking, and mobbing of predators. The vast majority of bird species are socially monogamous, usually for one breeding season at a time, sometimes for years, but rarely for life. Other species have breeding systems that are polygynous ("many females") or, rarely, polyandrous ("many males"). Eggs are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching.
Many species are of economic importance, mostly as sources of food acquired through hunting or farming. Some species, particularly songbirds and parrots, are popular as pets. Other uses include the harvesting of guano (droppings) for use as a fertiliser. Birds figure prominently in all aspects of human culture from religion to poetry to popular music. About 120–130 species have become extinct as a result of human activity since the 17th century, and hundreds more before then. Currently about 1,200 species of birds are threatened with extinction by human activities, though efforts are underway to protect them.
For more information about Bird, read the full article at
Wikipedia.
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News tagged with birds
Discovery raises new doubts about dinosaur-bird links
Other Sciences / Archaeology & Fossils
Jun 09, 2009 |
4.4 / 5 (24) |
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Researchers at Oregon State University have made a fundamental new discovery about how birds breathe and have a lung capacity that allows for flight - and the finding means it's unlikely that birds descended from any known ...
Canadian scientist aims to turn chickens into dinosaurs
Other Sciences / Archaeology & Fossils
Aug 25, 2009 |
4.1 / 5 (24) |
33
After years spent hunting for the buried remains of prehistoric animals, a Canadian paleontologist now plans to manipulate chicken embryos to show he can create a dinosaur.
Great Tit Turns Out to be a Killer
Sep 10, 2009 |
4.7 / 5 (21) |
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(PhysOrg.com) -- The Great Tit is an aggressive songbird found in Britain, continental Europe, parts of Northern Africa, and much of Asia. It is believed to survive mostly on seeds, nuts, fruit, insects, beetles, ...
Climate change makes migrations longer for birds
Apr 15, 2009 |
4.6 / 5 (21) |
2
Bird migrations are likely to get longer according to the first ever study of the potential impacts of climate change on the breeding and winter ranges of migrant birds.
Aesop's fable 'the crow and the pitcher' more fact than fiction (w/ Video)
Aug 06, 2009 |
4.8 / 5 (17) |
5
In Aesop's fable 'The crow and the pitcher' a thirsty crow uses stones to raise the level of water in a pitcher to quench its thirst. A new study published online today (06 August) in the journal Current Bi ...
New research challenges long-held assumptions of flightless bird evolution
Biology /
Sep 03, 2008 |
4.6 / 5 (17) |
3
Large flightless birds of the southern continents – African ostriches, Australian emus and cassowaries, South American rheas and the New Zealand kiwi – do not share a common flightless ancestor as once believed.
Warming brings more birds north in winter
Apr 06, 2009 |
4.6 / 5 (17) |
0
Long-term global warming is prompting North American birds to winter farther north -- a trend more noticeable in Alaska than anywhere else in the nation, according to a new study by the National Audubon Society.
T.rex 'followed its nose' while hunting
Biology /
Oct 29, 2008 |
4.8 / 5 (16) |
2
Although we know quite a bit about the lifestyle of dinosaur; where they lived, what they ate, how they walked, not much was known about their sense of smell, until now.
Meat-eating dinosaur from Argentina had bird-like breathing system
Other Sciences / Archaeology & Fossils
Sep 29, 2008 |
4.5 / 5 (15) |
2
The remains of a 30-foot-long predatory dinosaur discovered along the banks of Argentina's Rio Colorado is helping to unravel how birds evolved their unusual breathing system.
Airliners could save fuel by taking a hint from birds flying in formation
Jun 01, 2009 |
4.5 / 5 (14) |
3
(PhysOrg.com) -- From Leonardo da Vinci to the Greek tragedy of Icarus, birds have emboldened scientific minds to master flight. Now, Stanford researchers can be added to the list of ornithologically inspired ...
Trees evolved camouflage defense against long extinct predator: First evidence of camouflage defense in plants
Jul 22, 2009 |
4.4 / 5 (14) |
30
(PhysOrg.com) -- Many animal species such as snakes, insects and fish have evolved camouflage defences to deter attack from their predators. However research published in New Phytologist has discovered that t ...
Peckish bird briefly downs big atom smasher
Nov 09, 2009 |
3.9 / 5 (16) |
22
A peckish bird briefly knocked out part of the world's biggest atom smasher by causing a chain reaction with a piece of bread, the European Organisation for Nuclear Research (CERN) said Monday.
Extinct New Zealand eagle may have eaten humans
Other Sciences / Archaeology & Fossils
Sep 11, 2009 |
4.2 / 5 (14) |
3
(AP) -- Sophisticated computer scans of fossils have helped solve a mystery over the nature of a giant, ancient raptor known as the Haast's eagle which became extinct about 500 years ago, researchers said Friday.
Necessity is the mother of invention for clever birds (w/Videos)
May 25, 2009 |
4.8 / 5 (12) |
4
Researchers at the Universities of Cambridge and Queen Mary, University of London have found that rooks, a member of the crow family, are capable of using and making tools, modifying them to make them work and using two tools ...
Mockingbirds, no bird brains, can recognize a face in a crowd
May 18, 2009 |
4.5 / 5 (12) |
5
(PhysOrg.com) -- The birds are watching. They know who you are. And they will attack. Nope, not Hitchcock. It's science.
