Argentavis magnificens (literally "Magnificent Argentine Bird") is the largest flying bird ever discovered. The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene Epoch made up of two stages. ... Image File history File linksMetadata Size of this preview: 800 × 515 pixelsFull resolution (900 × 579 pixel, file size: 553 KB, MIME type: image/jpeg) My reconstruction of the giant teratorn Argentavis magnificens, of Late Miocene Argentina. ... The conservation status of a species is an indicator of the likelihood of that species continuing to survive either in the present day or the future. ... For other uses, see Fossil (disambiguation). ... For other uses, see Scientific classification (disambiguation). ... For other uses, see Animal (disambiguation). ... Typical Classes See below Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... For other uses, see Bird (disambiguation). ... Families Ardeidae Cochlearidae (the Boat-billed Heron) Balaenicipitidae (the Shoebill) Scopidae (the Hammerkop) Ciconiidae Threskiornithidae Cathartidae Traditionally, the order Ciconiiformes has included a variety of large, long-legged wading birds with large bills: storks, herons, egrets, ibises, spoonbills, and several others. ... Teratorns were very large birds of prey who lived in North and South America from Miocene to Pleistocene. ... Year 1980 (MCMLXXX) was a leap year starting on Tuesday (link displays the 1980 Gregorian calendar). ... This article does not cite any references or sources. ... Year 1980 (MCMLXXX) was a leap year starting on Tuesday (link displays the 1980 Gregorian calendar). ... For other uses, see Bird (disambiguation). ...

Sometimes called the Giant Teratorn, is an extinct species known from (as of 2006) three sites from the late Miocene (6 million years before present) of Central and Northwestern Argentina, South America, where a good sample of fossils has been obtained.^[1] Species Argentavis magnificens Argentavis magnificens is an extinct bird from the late Miocene (23 - 5 million years before present) of South America. ... For other uses, see Extinction (disambiguation). ... For other uses, see Species (disambiguation). ... The Miocene Epoch is a period of time that extends from about 23. ... South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ...

Physical characteristics

Currently accepted estimates:

• Wingspan: 5.8 to 8 m (19 - 26 ft)
• Wing area: nearly 7 square m (75 square ft)
• Wing loading: c. 11,5 kg/square m
• Length: 3.5 m (11.5 ft)
• Height: 1.7 to 2 m (5.6 ft - 6.5 ft)
• Weight: 65-100 kg (143 lb - 220 lb)

For comparison, the living bird with the largest wingspan is the Wandering Albatross (Diomedea exulans, 3.63 m). Since A. magnificens is known to have been a land bird, another good point of comparison is the Andean Condor, Vultur gryphus, which is not too distantly related to Argentavis. This bird is among the largest landbirds altogether, with a wingspan of about 3 m and weighing up to 12 kg. The largest known flying creatures ever were certain pterosaurs, extinct flying reptiles related to the dinosaurs. In 1971, remains of Quetzalcoatlus were found in Texas, The largest remains are inconclusive, and may indicate an individual with a wingspan as large as 18 m (59 ft).^{[citation needed]} Such a wingspan, however, may violate fundamental structural limits imposed on biological fliers; some scientists favor a wingspan closer to 12 m (40 ft) in light of these arguments. Before Quetzalcoatlus, the largest known pterosaur was Pteranodon, with individuals with 9 m (30 ft) wingspan.^[2] Binomial name Diomedea exulans Linnaeus, 1758 The Wandering Albatross (Diomedea exulans), is a large seabird from the family Diomedeidae which has a circumpolar range in the Southern Ocean. ... For other uses, see condor (disambiguation). ... Suborders Rhamphorhynchoidea Pterodactyloidea Pterosaurs (TEH-row-sore, winged lizards) were flying reptiles of the clade Pterosauria. ... Species Quetzalcoatlus northropi (type) Quetzalcoatlus, named after the Aztec feathered serpent god Quetzalcoatl, was a pterodactyloid pterosaur known from the Late Cretaceous of North America (Campanian–Maastrichtian stages, 84–65 ma), and one of the largest known flying animals of all time. ... Species (type) Pteranodon (from Greek πτερ- wing and αν-οδων toothless), from the Late Cretaceous (santonian-campanian, 85-82 million years ago) of North America (Kansas, Alabama, Nebraska, Wyoming, South Dakota) was one of the largest pterosaur genera, with a wingspan of up to 9 m (30 feet). ...

The heaviest extant flying bird is not heavier than 20 kg (several contenders, among which are the European Great Bustard Otis tarda and the African Kori Bustard Ardeotis kori). The Sarus Crane is the tallest flying bird alive, standing nearly as high as Argentavis due to its long legs. Binomial name Otis tarda Linnaeus, 1758 The Great Bustard, Otis tarda, is a very large bird in the bustard family. ... Wikipedia does not have an article with this exact name. ... Binomial name Grus antigone Linnaeus, 1758 The Sarus Crane (Grus antigone) is a resident breeding bird in northern India, Nepal, Southeast Asia and Queensland, Australia. ...

Flightlessness is not a simple question of weight, except in extreme cases. Site and structure of the wing must also be taken into account. As a rule-of-thumb, a wing loading of 25 kg/square m is considered the de facto limit for avian flight (Meunier, 1951). In aerodynamics, wing loading is the loaded weight of the aircraft divided by the area of the wing. ...

The humerus (upper arm bone) of Argentavis is somewhat damaged. It allows a fairly accurate estimate of its length in life, which was a bit shorter than an entire human arm (Campbell & Tonni, 1983). The species apparently had stout, strong legs and large feet which enabled it to walk with ease. The bill was large, rather slender, had a hooked tip and a wide gape. The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ...

Ecology

As with all extinct species not much can be known about the Giant Teratorn's behaviour. From the size and structure of its wings it is inferred that A. magnificens flew mainly by soaring, using flapping flight only during short periods. It is probable that it used thermal currents and the prevailing westerly winds that swept across the region (there were no sizable mountains in southern South America at the time). It has been estimated that the minimal velocity for the wing of A. magnificens is about 11 m/s or 40 km/h (Vizcaíno et al., 2000). Especially for takeoff, they would have depended on the wind, as although their legs were strong enough to provide them with a running or jumping start, the wings were simply too long to flap effectively until the bird was some meters off the ground (Campbell & Tonni, 1983).

This species seems not as well-suited for predation aerodynamically as its relatives. It probably preferred to scavenge for carrion, and it is likely that it habitually chased marsupial carnivores such as Thylacosmilidae from their kills. Unlike extant condors and vultures, the other species of teratorns also generally had long, eagle-like beaks and they are believed to have been active predators, being less ponderous than Argentavis. When hunting actively, A. magnificens would probably have swooped from high above onto their prey, which they usually would have been able to grab, kill, and swallow without landing. Skull structure makes Campbell and Tonni (1983) think that it ate most of its prey whole rather than tearing off pieces of flesh. Predator and Prey redirect here. ... Aerodynamics is a branch of fluid dynamics concerned with the study of gas flows, first analysed by George Cayley in the 1800s. ... This article is about mammals. ... Species Thylacosmilus was a saber-toothed marsupial predator that first appeared during the Miocene. ... Genera Several, see below. ...

Argentavis' territories measured probably more than 500 square km, which the birds screened for food, possibly utilizing a generally north-south direction to avoid being slowed by adverse winds. Comparison with extant birds suggests it laid one or two eggs with a mass of somewhat over 1 kg - somewhat smaller than an ostrich egg - every two years. Climate considerations make it likely that the birds incubated over the winter months, mates exchanging duties of incubating and procuring food every few days, and that the young were independent after some 16 months, but not fully mature until aged about a dozen years. Mortality must have been very low, with an estimated 2% of birds dying per year being close to the maximum possible while maintaining a viable population, but Argentavis suffered hardly any predation, thus mortality was mainly from old age, accidents and diseases (Palmqvist & Vizcaíno, 2003). As a comparison, the annual mortality rate for humans ranged between about 0.22 and 3% in 2007, according to the CIA estimate. In ethology, sociobiology and behavioral ecology, the term territory refers to any geographical area that an animal of a particular species consistently defends against conspecifics (and, occasionally, animals of other species). ... // Binomial name Carolus Linnaeus, 1758 The present-day distribution of Ostriches. ... Crude death rate by country Mortality rate is a measure of the number of deaths (in general, or due to a specific cause) in some population, scaled to the size of that population, per unit time. ... The CIA Seal The Central Intelligence Agency (CIA) is an American intelligence agency, responsible for obtaining and analyzing information about foreign governments, corporations, and individuals, and reporting such information to the various branches of the U.S. Government. ...

References

• Campbell, Kenneth E. Jr. & Tonni, E. P. (1980): A new genus of teratorn from the Huayquerian of Argentina (Aves: Teratornithidae). Contributions in Science, Natural History Museum of Los Angeles County 330: 59-68.

• Campbell, Kenneth E. Jr. & Tonni, E. P. (1983): Size and locomotion in teratorns. Auk 100(2): 390-403 PDF fulltext

• Meunier, K. (1951): Korrelation und Umkonstruktionen in den Größenbeziehungen zwischen Vogelflügel und Vogelkörper. Biologia Generalis 19: 403-443. [Article in German]

• Palmqvist, Paul & Vizcaíno, Sergio F. (2003): Ecological and reproductive constraints of body size in the gigantic Argentavis magnificens (Aves, Theratornithidae) from the Miocene of Argentina. Ameginiana 40(3): 379-385. PDF fulltext

• Vizcaíno, Sergio F.; Palmqvist, Paul & Fariña, Richard A. (2000): ¿Hay un límite para el tamaño corporal en las aves voladoras? [Is there a limit to body size in flying birds?]. Encuentros en la Biología 64 [Article in Spanish] HTML fulltext

The Auk is a quarterly journal and the official publication of the American Ornithologists Union, having been continuously published by that body since 1883. ... Peter Wellnhofer is a German paleontologist at the Bayerische Staatssammlung fur Paläontologie in Munich. ...

External Links

• BBC News: Ancient American bird was glider - BBC News article
• How the dinosaur bird took to the skies - Telegraph.co.uk article
• Secret of flight for world's largest bird revealed - PhysOrg.com article