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Anserimorphae
The Odontoanserae is a proposed clade that includes the family Pelagornithidae (pseudo-toothed birds) and the clade Anserimorphae (the order Anseriformes and their stem-relatives). The placement of the pseudo-toothed birds in the evolutionary tree of birds has been problematic, with some supporting the placement of them near the orders Procellariformes and Pelecaniformes based on features in the sternum. In 2005 a cladistic analysis had found support in placing pseudo-toothed birds as the sister group to waterfowl. Evidence for this comes from shared characteristics in the skull such as lack of a crest on the underside of the palatine bone and two condyles on the mandibular process of the quadrate bone, with the middle condyle beakwards of the side condyle. In addition to that, both groups have similar features in their pelvic and pectoral regions. Furthermore, a 2013 study on the growth pattern and structure of the pseudoteeth in ''Pelagornis mauretanicus'' shows more support of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastornithidae
''Gastornis'' is an extinct genus of large flightless birds that lived during the mid Paleocene to mid Eocene epochs of the Paleogene period. Fossils have been found in Europe, Asia and North America, with the remains from North America originally assigned to the genus ''Diatryma''. ''Gastornis'' species were very large birds, and have traditionally been considered to be predators of small mammals. However, several lines of evidence, including the lack of hooked claws in known ''Gastornis'' footprints and studies of their beak structure and isotopic signatures of their bones have caused scientists to reinterpret these birds as herbivores that probably fed on tough plant material and seeds. ''Gastornis'' is generally agreed to be related to Galloanserae, the group containing waterfowl and gamebirds. History ''Gastornis'' was first described in 1855 from a fragmentary skeleton. It was named after Gaston Planté, described as a "studious young man full of zeal", who had discover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastornis Giganteus Restoration
''Gastornis'' is an extinct genus of large flightless birds that lived during the mid Paleocene to mid Eocene epochs of the Paleogene period. Fossils have been found in Europe, Asia and North America, with the remains from North America originally assigned to the genus ''Diatryma''. ''Gastornis'' species were very large birds, and have traditionally been considered to be predators of small mammals. However, several lines of evidence, including the lack of hooked claws in known ''Gastornis'' footprints and studies of their beak structure and isotopic signatures of their bones have caused scientists to reinterpret these birds as herbivores that probably fed on tough plant material and seeds. ''Gastornis'' is generally agreed to be related to Galloanserae, the group containing waterfowl and gamebirds. History ''Gastornis'' was first described in 1855 from a fragmentary skeleton. It was named after Gaston Planté, described as a "studious young man full of zeal", who had discover ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastornithiformes
Gastornithiformes were an extinct order of giant flightless fowl with fossils found in North America, Eurasia, and possibly Australia. Members of Gastornithidae were long considered to be a part of the order Gruiformes. However, the traditional concept of Gruiformes has since been shown to be an unnatural grouping. Beginning in the late 1980s and the first phylogenetic analysis of gastornithid relationships, consensus began to grow that they were close relatives of the lineage that includes waterfowl and screamers, the Anseriformes. Recognizing the apparent close relationship between gastornis and waterfowl, some researchers even classify them within the anseriform group itself. Others restrict the name Anseriformes only to the crown group formed by all modern species, and label the larger group including extinct relatives of anseriformes in the clade Anserimorphae (which this article and related pages have adopted). While the order is generally considered to be monotypic, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromornithidae
Dromornithidae, known as mihirungs and informally as thunder birds or demon ducks, were a clade of large, flightless Australian birds of the Oligocene through Pleistocene Epochs. All are now extinct. They were long classified in Struthioniformes, but are now usually classified as galloanseres. Dromornithids were part of the Australian megafauna. One species, ''Dromornis stirtoni'', was tall. Only a single species, ''Genyornis newtoni'' survived into the Late Pleistocene. They are thought to have been herbivorous. The scientific name Dromornithidae derives from the Greek words , ("swift-running") and , ("bird"). Classification The family was named by Max Fürbringer in 1888, citing W. B. Clarke and Gerard Krefft, Owen's separation from ''" Dromaeus"'' and ''Dinornis'', and a note by von Haast allying ''Dromornis'' with ''Dromaeus''. What the nearest relatives of this group are is a controversial issue. For many years it was thought that dromornithids were related to ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anseriformes
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves. Due to their aquatic nature, most species are web-footed. Evolution Anseriformes are one of only two types of modern bird to be confirmed present during the Mesozoic alongside the other dinosaurs, and in fact were among the very few birds to survive their extinction, along with their cousins the galliformes. These two groups only occupied two ecological niches during the Mesozoic, living in water and on the ground, while the toothed enantiornithes were the dominant bird ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sibley–Ahlquist Taxonomy Of Birds
The Sibley–Ahlquist taxonomy is a bird taxonomy proposed by Charles Sibley and Jon E. Ahlquist. It is based on DNA–DNA hybridization studies conducted in the late 1970s and throughout the 1980s. DNA–DNA hybridization is among a class of comparative techniques in molecular biology that produce distance data (versus character data) and that can be analyzed to produce phylogenetic reconstructions only using phenetic tree-building algorithms. In DNA–DNA hybridization, the percent similarity of DNA between two species is estimated by the reduction in hydrogen bonding between nucleotides of imperfectly complemented heteroduplex DNA (i.e., double stranded DNAs that are experimentally produced from single strands of two different species), compared with perfectly matched homoduplex DNA (both strands of DNA from the same species). Characteristics The classification appears to be an early example of cladistic classification because it codifies many intermediate levels of taxa: th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagornis Chilensis EF
''Pelagornis'' is a widespread genus of prehistoric pseudotooth birds. These were probably rather close relatives of either pelicans and storks, or of waterfowl, and are here placed in the order Odontopterygiformes to account for this uncertainty. Description The fossil specimens show that ''P. miocaenus'' was one of the larger pseudotooth birds, hardly smaller in size than ''Osteodontornis'' or the older ''Dasornis''. Its head must have been about long in life, and its wingspan was probably more than , perhaps closer to . Unlike in its contemporary ''Osteodontornis'' but like in the older ''Pseudodontornis'', between each two of ''Pelagorniss large "teeth" was a single smaller one. ''Pelagornis'' differed from ''Dasornis'' and its smaller contemporary ''Odontopteryx'' in having no pneumatic foramen in the fossa pneumotricipitalis of the humerus, a single long latissimus dorsi muscle attachment site on the humerus instead of two distinct segments, and no prominent ligam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromornis BW
''Dromornis'' is a genus of large to enormous prehistoric birds. The species were flightless, possessing greatly reduced wing structures but with large legs, similar to the modern ostrich or emu. They were likely to have been predominantly, if not exclusively, herbivorous browsers. The male of the largest species, ''Dromornis stirtoni'', is a contender for the tallest and heaviest bird, and possibly exhibited aggressive territorial behaviour. They belong to the clade dromornithid, extinct flightless birds known as mihirungs. Taxonomy The genus was erected to separate a new species, ''Dromornis australis'', from the previously described ''Dinornis'' (giant moas), another lineage of ancient large and flightless birds found in New Zealand that was earlier described by Richard Owen in 1843. A femur that was forwarded to England, probably a dromornithid and since lost, suggested an Australian genus, but Owen withheld publication for many years. The type specimen, another femur, was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegavis Restoration
''Vegavis'' is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 68 to 66 mya. Among modern birds, most studies show that ''Vegavis'' is most closely related to ducks and geese (Anatidae), but it is not considered to be a direct ancestor of them, although other studies question these results. Taxonomy The holotype specimen of ''Vegavis'' is held by the Museo de La Plata, Argentina. The specimen, cataloged as MLP 93-I-3-1, was found in the López de Bertodano Formation at Cape Lamb on Vega Island, Antarctica, in 1993, but was only described as a new species in 2005 because it consists of the very delicate remains of one bird embedded in a concretion, which had to be meticulously prepared for study. CT scans were utilized to gain a clearer picture of the bone structure without running danger of damaging or destroying the fossil. The genus name, ''Vegavis'', is a combination of the name of Vega Island and "avis", the Lati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
