Citizendia

Gansus
Fossil range: Early Cretaceous
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Genus: Gansus
Hou & Liu, 1984
Binomial name
Gansus yumenensis
Hou & Liu, 1984

Gansus is a genus of aquatic birds that lived during the Albian stage of the Early Cretaceous period (around 110 million years ago) in what is now Gansu province, western China. The Early Cretaceous ( timestratigraphic name or the Lower Cretaceous ( logstratigraphic name is the earlier of the two major divisions of the Cretaceous Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Year 1984 ( MCMLXXXIV) was a Leap year starting on Sunday (link displays the 1984 Gregorian calendar) Year 1984 ( MCMLXXXIV) was a Leap year starting on Sunday (link displays the 1984 Gregorian calendar) A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Albian ( French Albion, from Alba = Aube in France) is a stage of the Cretaceous period. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of In Astronomy, Geology, and Paleontology, mya or " mya " is an abbreviation for "million years ago". ( is a province located in the northwest of the People's Republic of China. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National It is the oldest-known of the Ornithurae, the group which includes modern birds (Neornithes) and extinct related groups, such as Ichthyornithes and Hesperornithes. Ornithurae (meaning "bird tails" in Greek) is the name of a natural group of Birds coined by Ernst Haeckel in 1866 Modern birds (subclass Neornithes) are the members of class Aves that have survived into recent times and have coexisted with Humans Modern birds are Ichthyornis is a Genus of Seabird from the Late Cretaceous of North America. Hesperornithes is an extinct and highly specialized Clade of Cretaceous toothed Birds Hesperornithine birds apparently limited to former aquatic habitats

The genus contains a single species, G. yumenensis, which was about the size of a pigeon and similar in appearance to loons and diving ducks. The loons (eg North America or divers (eg UK/Ireland are a group of aquatic birds found in many parts of North America and northern Eurasia The 15 or so living species of diving duck, commonly called pochards or scaups, are part of the diverse and very large Duck, Goose [1] It had most modern bird features, with exceptions such as its clawed wingtips and its lack of hollow bones, both of which may have impaired its flight slightly.

The Ornithurae form a clade which contains all living birds and their closest relatives). Ornithurae (meaning "bird tails" in Greek) is the name of a natural group of Birds coined by Ernst Haeckel in 1866 A clade is a taxonomic group comprising a single Common ancestor and all the descendants of that ancestor All extant birds, including taxa as diverse as ostriches, hummingbirds and eagles, are descended from basal Ornithurans. A taxon (plural taxa) or taxonomic unit, is a name designating an organism or a group of Organisms In Biological nomenclature according to The Ostrich ( Struthio camelus) is a large Flightless bird native to Africa (and formerly the Middle East) Hummingbirds are Birds in the family Trochilidae, and are endemic to the Americas. Eagles are large birds of prey which are members of the Bird order Falconiformes and family Accipitridae, and belong to several genera It is now thought entirely possible that all birds descended specifically from a semi-aquatic bird similar to Gansus. Thus, while Gansus is not necessarily a direct ancestor of today's birds, it is closely related to such an ancestral species. It is the oldest modern bird known to date. A thorough comparison of G. yumenensis to the Hesperornithes may prove especially fruitful, as the assignment of the latter to the Ornithurae is not altogether certain because of their extreme specialization (e. g. their feet that were carried splayed sidewards and their near-complete loss of wings).

Gansus was discovered in the form of a single fossil foot in 1981. Then five well-preserved fossils were found in 2003–2004 in mudstone at the site of an ancient lake at Changma, Gansu; the geological stratum in which the fossils were found is the Xiagou Formation. Mudstone (also called mudrock) is a fine grained Sedimentary rock whose original constituents were Clays or Muds Grain size is up The Xiagou Formation is the middle unit of the Xinminpu Group Their bodies had settled in anoxic mud and were soon covered with further extremely fine silty sediments. Without oxygen, their remains resisted decay: these specimens preserved remains of flight feathers and traces of the webbing between their toes. Flight feathers are the long stiff asymmetrically shaped but symmetrically paired Feathers on the Wings or Tail of a Bird; those on the [2]

References

Footnotes

  1. ^ MSNBC (2006-06-15). MSNBC is a 24-hour cable television news channel based in the United States and available in Canada. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 763 BC - Assyrians record a Solar eclipse that will be used to fix the Chronology of Mesopotamian history Waterfowl fossils fill in a big missing link: 110 million-year-old birds bridge gap between age of dinosaurs and today. Retrieved on 2006-06-15. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 763 BC - Assyrians record a Solar eclipse that will be used to fix the Chronology of Mesopotamian history
  2. ^ Norris, Scott (2006-06-15). Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 763 BC - Assyrians record a Solar eclipse that will be used to fix the Chronology of Mesopotamian history Dinosaur-Era Birds Surprisingly Ducklike, Fossils Suggest. National Geographic Society. Overview The NGS's historical mission is "to increase and diffuse geographic knowledge while promoting the conservation of the world's cultural historical and natural Retrieved on 2006-06-15. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 763 BC - Assyrians record a Solar eclipse that will be used to fix the Chronology of Mesopotamian history


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