The phylogenetic relationships of early dinosaurs: a comparative report

@article{Sereno2007ThePR,
  title={The phylogenetic relationships of early dinosaurs: a comparative report},
  author={Paul C. Sereno},
  journal={Historical Biology},
  year={2007},
  volume={19},
  pages={145 - 155}
}
  • P. Sereno
  • Published 1 January 2007
  • Environmental Science
  • Historical Biology
Surprising new anatomical information has come to light for the early dinosaurs Eoraptor lunensis and Herrerasaurus ischigualastensis. Eoraptor has a mid mandibular jaw joint, and Herrerasaurus has a promaxillary fenestra at the anterior end of the antorbital fossa. Initial cladistic interpretation placed Herrerasaurus outside Dinosauria. Since then, Eoraptor and Herrerasaurus have been placed at the base of Saurischia or within Theropoda in two large-scale quantitative analyses. A comparative… 

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  • Geography, Environmental Science
  • 2014
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References

SHOWING 1-10 OF 52 REFERENCES

Early dinosaurs: A phylogenetic study

A new cladistic analysis of the early dinosaur radiation was performed to assess the relationships among the three major clades (Ornithischia, Sauropodomorpha and Theropoda) and to define the phylogenetic position of the basal members of the group.

Primitive dinosaur skeleton from Argentina and the early evolution of Dinosauria

The discovery of Eoraptor supports the hypothesis that dinosaurs diverged rapidly at small body size from a common ancestor, with the principal herbivorous and carnivorous lineages present by the middle Carnian.

Dinosaurian precursors from the Middle Triassic of Argentina: Marasuchus lilloensis, gen. nov.

Several synapomorphies unite Marasuchus and dinosaurs (as Dinosauriformes) to the exclusion of the contemporary dinosauromorph Lagerpeton and pterosaurs.

Basal Dinosauriform Remains from Britain and the Diagnosis of the Dinosauria

The definition and diagnosis of the Dinosauria are restated and the positions of the new form, herrerasaurs and Eoraptor relative to true dinosaurs are discussed.

New information on the systematics and postcranial skeleton of Herrerasaurus ischigualastensis (Ther

New evidence supports this group as saurischian dinosaurs: the posterior process of the jugal is forked, a hyposphene-hypantrum articulation is present in dorsal vertebrae, the distal shaft of the ischium is rod-like, and six other saurishian synapomorphies are present.

The Complete Skull and Skeleton of an Early Dinosaur

Fossils of Herrerasaurus and younger dinosaurs from Upper Triassic beds in Argentina suggest that the dinosaurian radiation was well under way before dinosaurs dominated terrestrial vertebrate communities in taxonomic diversity and abundance.

THE ORIGIN AND EVOLUTION OF DINOSAURS

  • P. Sereno
  • Geography, Environmental Science
  • 1997
The phylogenetic history of ornithischian and saurischian dinosaurs reveals evolutionary trends such as increasing body size and Adaptations to herbivory in dinosaurs were not tightly correlated with marked floral replacements.

The evolution of dinosaurs.

  • P. Sereno
  • Environmental Science, Geography
    Science
  • 1999
The ascendancy of dinosaurs on land near the close of the Triassic now appears to have been as accidental and opportunistic as their demise and replacement by therian mammals at the end of the

The skull and neck of the basal theropod Herrerasaurus ischigualastensis

The skull of Herrerasaurus ischigualastensis has a rectangular profile and a transversely narrow snout and other features of the skull constitute dinosaurian synapomorphies, such as the loss of the postfrontal and small post-temporal opening.

Faunal replacement in the Triassic of South America

Improvements in the locomotor apparatus are discernible in seven groups of archosaurs and indicate that a great adaptive radiation took place before the oldest recorded fauna dominated by archosaurs appeared.
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