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Citation for Study 13163

Citation title: "Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira.".

Study name: "Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira.".

This study is part of submission 13163 (Status: Published).

Citation

Nesbitt S.J., Sidor C.A., Irmis R.B., Angielczyk K.D., Smith R.M., & Tsuji L.A. 2010. Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira. Nature, 464(7285): 95-98.

Authors

• Nesbitt S.J.
• Sidor C.A.
• Irmis R.B.
• Angielczyk K.D.
• Smith R.M.
• Tsuji L.A.

Abstract

The early evolutionary history of Ornithodira (avian-line archosaurs) has hitherto been documented by incomplete (Lagerpeton) or unusually specialized forms (pterosaurs and Silesaurus). Recently, a variety of Silesaurus-like taxa have been reported from the Triassic period of both Gondwana and Laurasia, but their relationships to each other and to dinosaurs remain a subject of debate. Here we report on a new avian-line archosaur from the early Middle Triassic (Anisian) of Tanzania. Phylogenetic analysis places Asilisaurus kongwe gen. et sp. nov. as an avian-line archosaur and a member of the Silesauridae, which is here considered the sister taxon to Dinosauria. Silesaurids were diverse and had a wide distribution by the Late Triassic, with a novel ornithodiran bauplan including leaf-shaped teeth, a beak-like lower jaw, long, gracile limbs, and a quadrupedal stance. Our analysis suggests that the dentition and diet of silesaurids, ornithischians and sauropodomorphs evolved independently from a plesiomorphic carnivorous form. As the oldest avian-line archosaur, Asilisaurus demonstrates the antiquity of both Ornithodira and the dinosaurian lineage. The initial diversification of Archosauria, previously documented by crocodilian-line archosaurs in the Anisian, can now be shown to include a contemporaneous avian-line radiation. The unparalleled taxonomic diversity of the Manda archosaur assemblage indicates that archosaur diversification was well underway by the Middle Triassic or earlier.

External links

• DOI: 10.1038/nature08718
• PMID: 20203608
• Other URL: http://graemetlloyd.com/matr.html

About this resource

• Canonical resource URI: http://purl.org/phylo/treebase/phylows/study/TB2:S13163
• Other versions: Nexus NeXML
• Show BibTeX reference

  		@ARTICLE{TreeBASE2Ref21126,
  	 author = {Sterling J. Nesbitt and Christian A. Sidor and Randall B. Irmis and Kenneth D. Angielczyk and Roger  M. H. Smith and Linda A. Tsuji},
  	 title = {Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira.},
  	 year = {2010},
  	 keywords = {},
  	 doi = {10.1038/nature08718},
  	 url = {http://graemetlloyd.com/matr.html},
  	 pmid = {20203608},
  	 journal = {Nature},
  	 volume = {464},
  	 number = {7285},
  	 pages = {95--98},
  	 abstract = {The early evolutionary history of Ornithodira (avian-line archosaurs) has hitherto been documented by incomplete (Lagerpeton) or unusually specialized forms (pterosaurs and Silesaurus). Recently, a variety of Silesaurus-like taxa have been reported from the Triassic period of both Gondwana and Laurasia, but their relationships to each other and to dinosaurs remain a subject of debate. Here we report on a new avian-line archosaur from the early Middle Triassic (Anisian) of Tanzania. Phylogenetic analysis places Asilisaurus kongwe gen. et sp. nov. as an avian-line archosaur and a member of the Silesauridae, which is here considered the sister taxon to Dinosauria. Silesaurids were diverse and had a wide distribution by the Late Triassic, with a novel ornithodiran bauplan including leaf-shaped teeth, a beak-like lower jaw, long, gracile limbs, and a quadrupedal stance. Our analysis suggests that the dentition and diet of silesaurids, ornithischians and sauropodomorphs evolved independently from a plesiomorphic carnivorous form. As the oldest avian-line archosaur, Asilisaurus demonstrates the antiquity of both Ornithodira and the dinosaurian lineage. The initial diversification of Archosauria, previously documented by crocodilian-line archosaurs in the Anisian, can now be shown to include a contemporaneous avian-line radiation. The unparalleled taxonomic diversity of the Manda archosaur assemblage indicates that archosaur diversification was well underway by the Middle Triassic or earlier.}
  }
  		

• Show RIS reference

  		TY  - JOUR
  ID  - 21126
  AU  - Nesbitt,Sterling J.
  AU  - Sidor,Christian A.
  AU  - Irmis,Randall B.
  AU  - Angielczyk,Kenneth D.
  AU  - Smith,Roger  M. H.
  AU  - Tsuji,Linda A.
  T1  - Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira.
  PY  - 2010
  KW  - 
  UR  - http://graemetlloyd.com/matr.html
  N2  - The early evolutionary history of Ornithodira (avian-line archosaurs) has hitherto been documented by incomplete (Lagerpeton) or unusually specialized forms (pterosaurs and Silesaurus). Recently, a variety of Silesaurus-like taxa have been reported from the Triassic period of both Gondwana and Laurasia, but their relationships to each other and to dinosaurs remain a subject of debate. Here we report on a new avian-line archosaur from the early Middle Triassic (Anisian) of Tanzania. Phylogenetic analysis places Asilisaurus kongwe gen. et sp. nov. as an avian-line archosaur and a member of the Silesauridae, which is here considered the sister taxon to Dinosauria. Silesaurids were diverse and had a wide distribution by the Late Triassic, with a novel ornithodiran bauplan including leaf-shaped teeth, a beak-like lower jaw, long, gracile limbs, and a quadrupedal stance. Our analysis suggests that the dentition and diet of silesaurids, ornithischians and sauropodomorphs evolved independently from a plesiomorphic carnivorous form. As the oldest avian-line archosaur, Asilisaurus demonstrates the antiquity of both Ornithodira and the dinosaurian lineage. The initial diversification of Archosauria, previously documented by crocodilian-line archosaurs in the Anisian, can now be shown to include a contemporaneous avian-line radiation. The unparalleled taxonomic diversity of the Manda archosaur assemblage indicates that archosaur diversification was well underway by the Middle Triassic or earlier.
  L3  - 10.1038/nature08718
  JF  - Nature
  VL  - 464
  IS  - 7285
  SP  - 95
  EP  - 98
  ER  -