Neornithes

Neornithes
Black- browed albatross ( Thalassarche melanophris )
Systematics
Class : Birds (aves) without rank: Pygostylia without rank: Ornithothoraces without rank: Ornithurae without rank: Carinatae without rank: Neornithes
Scientific name
Neornithes
Gadow , 1893
Subclasses
Great Pine Birds (Palaeognathae) New-jawed birds (Neognathae)

The Neornithes ( recent birds or modern birds - also "modern birds") as a subgroup of the class of birds include all birds living today, all extinct birds of the Cenozoic era and some bird species from the Cretaceous period . The taxon (systematic unity) has been held since its introduction by Gadow (1893), especially in the paleornithology modern in delineating groups of birds to extinct bird groups of Mesozoic use and provides the Crown group is the birds.

In recent biology, “birds” (Aves) as a group name is often used synonymously with the group Neornithes. According to the definition of the American vertebrate paleontologist Jacques Gauthier (1986), Aves and Neornithes are actually synonyms. Instead, Gauthier introduces the name Avialae for the fossil core group representatives and the recent birds .

features

According to Hope (2002), modern birds have the following common derived characteristics : fusion of the maxillary and premaxillary bones ; the maxillary is greatly reduced and primarily limited to the palate region ; the mandibular symphyses are fused together; Merging of dental and surangular ; the lack of teeth; the shoulder joint pit of the raven bone is laterally no more extensive than the shoulder blade attachment of the raven bone; the shoulder joint fossa on the shoulder blade is oriented laterally or forward-laterally; the shoulder joint pit of the raven bone is z. T. or completely separated from that of the shoulder blade; the shoulder joint head is large; the indentation for the upper arm ligament clearly pronounced; the deltopectoral ridge of the upper arm is bent forward and the pneumotricipital recess is perforated due to a pneumatic opening.

phylogenesis

The oldest reliable evidence for the Neornithes is Vegavis iaai , a geese whose fossils were discovered in sedimentary rocks of the Antarctic Vega Island (Clarke et al. 2005). The formation time of the fossil occurrence falls in the Maastrichtian . Further representatives of modern bird orders from the Upper Cretaceous Period have been described, but due to the fragmentary preservation of the underlying fossils, all of them are considered dubious.

Whether the adaptive radiation of the Neornithes essentially took place before or after the Cretaceous-Tertiary boundary is controversial: While the lack of fossil evidence from the Cretaceous and the appearance of all modern orders in the Paleocene and Eocene (e.g. Dyke et al. 2004) as Evidence for a rapid radiation of the neornithes after the mass extinction at the end of the Cretaceous period is assessed (Feduccia 2003), all molecular biological findings consistently point to an origin of modern bird orders long before the end of the Cretaceous period (e.g. Slack et al. 2006, Harrison et al. 2004) . According to a model that takes both paleontological and molecular biological results into account, a large number of lines of development of modern birds have existed since the Cretaceous, but ecological diversification within individual modern groups did not occur until the beginning of the Tertiary (Harrison et al. 2004).

According to this view , the two subgroups of Neornithes that still occur today, the flightless primitive jaw birds ( Palaeognathae) and the new jaw birds (Neognathae), diverged in the Lower Cretaceous around 100 million years ago . The morphologically similar groups of chicken (Galliformes) and goose birds (Anseriformes) (anatomical comparison: see Dzerzhinsky 1995) form the taxon Galloanserae , whose ancestral form was separated in the early Upper Cretaceous from the ancestral form of the Neoaves , which include all other bird groups of the new pine birds .

The biological systematics of birds, including the Pygostylia group and new findings on the relationships between Mesozoic birds, is as follows:

Aves ("Avialae" after Fastovsky and Weishampel 2005)	Pygostylia    Confuciusornithidae      ? Oviraptorosaur (not to birds according to Fastovsky and Weishampel 2005)   Ornithothoraces    Enantiornithes   Ornithuromorpha    Patagopteryx      Vorona   Ornithurae    Hesperornithiformes   Carinatae    Ichthyornithiformes      Neornithes ("Aves" after Fastovsky and Weishampel 2005)      Archeopterygidae      Rahonavis      Jeholornis

Individual evidence

1. ^ H. Gadow: Vogel II: Systematischer Part. In: HG Bronn (Ed.): Classes and orders of the Thier-Reich. vol. 6 (4), CF Winter, Leipzig 1893.
2. ^ J. Gauthier: Saurischian monophyly and the origin of birds. In Memoires of the California Academy of Sciences. 8, 1986, pp. 1-55.
3. ↑ S. Hope: The Mesozoic radiation of Neornithes. In: L. Chiappe, L. Witmer (Eds.): Mesozoic Birds: Above the Heads of Dinosaurs. 2002, pp. 339-388.
4. ^ JA Clarke, CP Tambussi, JI Noriega, GM Erickson, RA Ketcham: Definitive fossil evidence for the extent of avian radiation in the Cretaceous. In: Nature 433, 2005, pp. 305-308.
5. ↑ G. Dyke, M. van Tuinen: The evolutionary radiation of modern birds (Neornithes): reconciling molecules, morphology and the fossil record. In: Zoological Journal of the Linnean Society. 141, 2004, pp. 153-177.
6. ^ A. Feduccia: Big Bang for Tertiary Birds? In: Trends in Ecology and Evolution. 18 (4), 2003, pp. 172-176.
7. ↑ KE Slack, CM Jones, T. Ando, ​​GL Harrison, RE Fordyce, U. Arnason, D. Penny: Early Penguin Fossils, Plus Mitochondrial Genomes, Calibrate Avian Evolution. In: Mol. Biol. Evol. 23 (6), 2006, pp. 1144-1155.
8. ↑ ^{a b} G.L. Harrison, PA McLenachan, MJ Phillips, KE Slack, A. Cooper, D. Penny: New Avian Mitochondrial Genomes Help Get to Basic Evolutionary Questions in the Late Cretaceous. In: Mol. Biol. Evol. 21 (6), 2004, pp. 974-983.
9. ↑ F. Ya. Dzerzhinsky: Evidence for the common ancestry of Galliformes and Anseriformes. In: Courier Research Institute Senckenberg. 181, 1995, pp. 325-336.
10. ↑ Michael J. Benton: Vertebrate Palaeontology. 3. Edition. Blackwell, Malden 2005, ISBN 0-632-05637-1 .
11. ↑ ^{a b c d} David E. Fastovsky, David B. Weishampel: The Evolution and Extinction of the Dinosaurs. 2nd Edition. Cambridge University Press, Cambridge 2005, ISBN 0-521-01046-2 .
12. ↑ Zhonghe Zhou: The origin and early evolution of birds: discoveries, disputes and perspectives from fossil evidence. In: Natural Sciences. 91, No. 10, 2004, pp. 455-471, doi : 10.1007 / s00114-004-0570-4 .