The Evolution of Dinosaurs

Sereno, Paul C.

doi:10.1126/science.284.5423.2137

Cited by 751 publications

(864 citation statements)

References 100 publications

Supporting

Mentioning

815

Contrasting

Unclassified

Order By: Relevance

“…Psittacosaurus) and non-iguanodontian ornithopods were bipedal (e.g. Sereno 1997Sereno , 1999Weishampel et al 2004). However, mosaic distributions of these features in other taxa has led to controversy over stance in several groups, primarily in hadrosaurids and other iguanodontian ornithopods (e.g.…”

Section: Determining Stance In Ornithischiansmentioning

confidence: 99%

“…Yates and Kitching 2003;Bonnan and Yates 2007;Yates et al 2010), while the first quadrupedal thyreophoran is known from the basal Jurassic (Owen 1861). The other two reversions, in Ceratopsia and Hadrosauriformes, happened much later in time, during the late Early to early Late Cretaceous (Sereno 1999;Weishampel et al 2004). Another possible independent reversion also occurred in rhabdodontid ornithopods, although the time that this occurred is unclear due to the extensive ghost lineage separating this clade from other ornithopods (Weishampel et al 2003;Maidment and Barrett 2014).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The evolution of ornithischian quadrupedality

Barrett

Maidment

2017

J Iber Geol

View full text Add to dashboard Cite

Ornithischian dinosaurs were primitively bipedal, but reverted to quadrupedality on at least three (and potentially several more) occasions: in Ceratopsia, Thyreophora and Hadrosauriformes. Each of these reversals was accompanied by anatomical changes to the whole skeleton that enabled the forelimb to function in weight bearing and that also resulted in numerous changes to the hip and hind limb musculature. Each quadrupedal clade acquired a suite of similar biomechanical characters, although they varied in terms of function and in how these character complexes were assembled. Some similar changes occurred in parallel among sauropodomorph dinosaurs as they transitioned from bipedality to quadrupedality. It is unclear why bipedal ornithischians reverted to quadrupedalism, but neither increases in body size nor the acquisition of dermal armour seem to have played a significant role. Increased head size might have influenced the position of the centre of mass and stance in ceratopsians and it is plausible that the evolution of herbivory played an important role in both ornithischians and sauropods, but the latter hypothesis is difficult to test.Resumen Los dinosaurios Ornitísquios, bípedos en origen, revertieron a la condición cuadrúpeda en al menos tres (y potencialmente más) ocasiones: en Ceratopsia, Thyreophora y Hadrosauriformes. Cada una de estas reversiones vino acompañada de cambios anatómicos en el resto de esqueleto que permitieron a la extremidad anterior funcionar para soportar su peso y llevaron a cambios en la cadera y la musculatura dela extremidad posterior. Cada clado cuadrúpedo adquirió una serie de caracteres biomecánicos parecidos, aunque variaron en su función y en la manera en la que estos conjuntos de caracteres encajaban. Cambios parecidos aparecieron paralelamente entre los dinosaurios sauropodomorfos durante su transición de bípedos a cuadrúpedos. Aunque no queda claro por qué los ornitísquios revertieron al cuadrupedismo, ni el aumento de masa corporal ni la adquisición de armadura parecen haber jugado un papel significativo. Un mayor tamaño de la cabeza pudo haber repercutido en el cambio de posición del centro de masas y cambio en la postura en los ceratopsios, y es posible que la evolución de la fitofagia jugara un papel importante, tanto en ornitísquios como saurópodos, aunque sea una hipótesis difícilmente contrastable.Palabras clave Ornithischia Á Dinosauria Á Locomoción Á Cuadrupedismo Á Biomecánica Á Morfología funcional Á Evolución

show abstract

Section: Determining Stance In Ornithischiansmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The evolution of ornithischian quadrupedality

Barrett

Maidment

2017

J Iber Geol

View full text Add to dashboard Cite

show abstract

“…The advent of numerical cladistic analyses in the mid 1980s crystallized support for both dinosaur monophyly and the hypothesis that birds evolved from theropod dinosaurs (e.g., Gauthier, 1986;Benton and Clark, 1988;Sereno, 1991a). Today, higher-level phylogenetic analyses continue to find robust support for dinosaur monophyly (e.g., Juul, 1994;Benton, 1999Benton, , 2004Sereno, 1999;Ezcurra, 2006;Langer and Benton, 2006;Irmis et al, 2007a;Brusatte et al, 2008a;Nesbitt et al, 2009b;Brusatte et al, 2010b;Nesbitt et al, 2010), although the exact characters diagnosing the dinosaur group continue to change as new fossils are found and old ideas are reinterpreted.…”

Section: Dinosauria: Diagnosismentioning

confidence: 99%

The origin and early radiation of dinosaurs

Brusatte

Nesbitt

Irmis

et al. 2010

Earth-Science Reviews

235

210

View full text Add to dashboard Cite

Dinosaurs were remarkably successful during the Mesozoic and one subgroup, birds, remain an important component of modern ecosystems. Although the extinction of non-avian dinosaurs at the end of the Cretaceous has been the subject of intense debate, comparatively little attention has been given to the origin and early evolution of dinosaurs during the Late Triassic and Early Jurassic, one of the most important evolutionary radiations in earth history. Our understanding of this keystone event has dramatically changed over the past 25 years, thanks to an influx of new fossil discoveries, reinterpretations of long-ignored specimens, and quantitative macroevolutionary analyses that synthesize anatomical and geological data. Here we provide an overview of the first 50 million years of dinosaur history, with a focus on the large-scale patterns that characterize the ascent of dinosaurs from a small, almost marginal group of reptiles in the Late Triassic to the preeminent terrestrial vertebrates of the Jurassic and Cretaceous. We provide both a biological and geological background for early dinosaur history. Dinosaurs are deeply nested among the archosaurian reptiles, diagnosed by only a small number of characters, and are subdivided into a number of major lineages. The first unequivocal dinosaurs are known from the late Carnian of South America, but the presence of their sister group in the Middle Triassic implies that dinosaurs possibly originated much earlier. The three major dinosaur lineages, theropods, sauropodomorphs, and ornithischians, are all known from the Triassic, when continents were joined into the supercontinent Pangaea and global climates were hot and arid. Although many researchers have long suggested that dinosaurs outcompeted other reptile groups during the Triassic, we argue that the ascent of dinosaurs was more of a matter of contingency and opportunism. Dinosaurs were overshadowed in most Late Triassic ecosystems by crocodile-line archosaurs and showed no signs of outcompeting their rivals. Instead, the rise of dinosaurs was a two-stage process, as dinosaurs expanded in taxonomic diversity, morphological disparity, and absolute faunal abundance only after the extinction of most crocodile-line reptiles and other groups.

show abstract

“…Sauropodomorpha fue definido por Salgado et al (1997a) como "el clado que incluye al ancestro común más reciente (Novas, 1994;Sereno, 1999Sereno, , 2006Tykoski, 2005;Ezcurra, 2010); incluso fue considerado como un saurisquio basal por fuera de Theropoda y Sauropodomorpha (Langer, 2004;. Luego de una re-preparación del material original, re-codificación e inclusión en matrices filogenéticas con mayor muestreo de taxones y caracteres,…”

Section: Acknowledgmentsunclassified

Reptiles Extintos - Volumen en Homenaje a Zulma Gasparini

2015

PE-APA

View full text Add to dashboard Cite

The Evolution of Dinosaurs

Cited by 751 publications

References 100 publications

The evolution of ornithischian quadrupedality

The evolution of ornithischian quadrupedality

The origin and early radiation of dinosaurs

Reptiles Extintos - Volumen en Homenaje a Zulma Gasparini

Contact Info

Product

Resources

About