A Basal Dinosaur from the Dawn of the Dinosaur Era in Southwestern Pangaea

  title={A Basal Dinosaur from the Dawn of the Dinosaur Era in Southwestern Pangaea},
  author={Ricardo N. Mart{\'i}nez and Paul C. Sereno and Oscar A. Alcober and Carina E. Colombi and Paul R. Renne and Isabel Patricia Monta{\~n}ez and Brian S. Currie},
  pages={206 - 210}
Two hundred thirty million years ago, in what is now Argentina, dinosaurs could be found as the dominant carnivores or as small herbivores. Upper Triassic rocks in northwestern Argentina preserve the most complete record of dinosaurs before their rise to dominance in the Early Jurassic. Here, we describe a previously unidentified basal theropod, reassess its contemporary Eoraptor as a basal sauropodomorph, divide the faunal record of the Ischigualasto Formation with biozones, and bracket the… 
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Basal dinosauriform and theropod dinosaurs from the mid–late Norian (Late Triassic) of Poland: implications for Triassic dinosaur evolution and distribution
The rise of dinosaurs during the Triassic is a widely studied evolutionary radiation, but there are still many unanswered questions about early dinosaur evolution and biogeography that are hampered
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An enigmatic plant-eating theropod from the Late Jurassic period of Chile
A new, bizarre herbivorous basal tetanuran from the Upper Jurassic of Chile challenges the conception that early theropod evolution is currently interpreted as the diversification of various carnivorous and cursorial taxa.
A new Late Triasssic phytogeographical scenario in westernmost Gondwana.
The Onslow floral belt is extended, previously recognized from the western edge of Tethys to Timor, to the western margin of South America, which has implications for palaeophytogeography, palaeoclimate reconstructions and the palaeoecology of a Triassic ecosystem.
Vertebrate Succession in the Ischigualasto Formation
ABSTRACT The Upper Triassic (Carnian—Norian) Ischigualasto Formation has yielded a diverse vertebrate fauna that records the initial phase of dinosaur evolution. Radioisotopic dates from ash layers
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  • Geography, Environmental Science
  • 2014
Research this century has greatly improved our knowledge of the origin and early radiation of dinosaurs. The unearthing of several new dinosaurs and close out- groups from Triassic rocks from various
Dinosaur diversification linked with the Carnian Pluvial Episode
Palaeontological and dated stratigraphic evidence is synthesized to show that dinosaur diversification followed the Carnian Pluvial Episode 234–232 mya, a time when climates switched from arid to humid and back to arid again.
The Carnian Pluvial Episode and the origin of dinosaurs
We present new evidence for a major inflection point in the history of tetrapods on land, a jump in the diversification of archosauromorphs, primarily dinosaurs, at 232–230 Ma. This corresponds to a


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Dating of sanidine from a bentonite interbedded in the Ischigualasto Formation of northwestern Argentina yielded a plateau age of 227.8 � 0.3 million years ago, diminishing the magnitude of the proposed late Carnian tetrapod extinction event.
The evolution of dinosaurs.
  • P. Sereno
  • Environmental Science, Geography
  • 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
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The oldest unequivocal records of Dinosauria were unearthed from Late Triassic rocks accumulated over extensional rift basins in southwestern Pangea, and the group achieved a nearly global distribution by the latest Triassic, especially with the radiation of saurischian groups such as “prosauropods” and coelophysoids.
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.
A Complete Skeleton of a Late Triassic Saurischian and the Early Evolution of Dinosaurs
A new theropod dinosaur from New Mexico is a representative of the early North American diversification and reveals a mosaic of plesiomorphic and derived features that clarify early saurischian dinosaur evolution and provide evidence for the antiquity of novel avian character systems including skeletal pneumaticity.
A critical re‐evaluation of the Late Triassic dinosaur taxa of North America
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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.