The phylogeny of the ornithischian dinosaurs

Butler, Richard J.; Upchurch, Paul; Norman, David

doi:10.1017/s1477201907002271

Cited by 265 publications

(569 citation statements)

References 102 publications

Supporting

Mentioning

552

Contrasting

Unclassified

Order By: Relevance

“…The main sources of our characters were Gauthier (1986), Sereno (1991), Langer and Benton (2006), Yates (2007), Butler et al (2008), , Nesbitt (2011) and Pol et al (2011).…”

Section: Further Discussion Of the Main Phylogenetic Analysesmentioning

confidence: 99%

A new hypothesis of dinosaur relationships and early dinosaur evolution

Baron

Norman

Barrett

2017

Nature

Self Cite

229

305

View full text Add to dashboard Cite

Further discussion of the main phylogenetic analysesTrees were produced and analysed in TNT 1.5-beta (Goloboff et al. 2008). In total 74 taxa were scored for 457 characters. Using the new technology search function, with ratchet and drift set to their defaults (10 iterations and 10 cycles respectively) and with 100 random additional sequences, our data produced 93 MPTs of length 1734. Bremer supports were also calculated using TNT 1.5-beta.The following characters were treated as ordered: 24, 35, 39, 60, 68, 71, 117, 145, 167, 169, 174, 180, 197, 199, 206, 214, 215, 222, 251, 269, 272, 286, 289, 303, 305, 307, 313, 322, 333, 334, 338, 353, 360, 376, 378, 387, 393, 442, 446 Our characters were drawn and modified from a number of previous studies and supplemented with an additional 63 novel characters. The main sources of our characters were Gauthier (1986), Sereno (1991), Langer and Benton (2006), Yates (2007), Butler et al. (2008), , Nesbitt (2011) and Pol et al. (2011).Our investigations and analyses showed that a number of characters previously thought only to appear in theropods or sauropodomorphs (or both) can also found in a several ornithischian taxa and, conversely, a number of features traditionally associated with basal ornithischian taxa are also present in basal theropods and, in some instances, sauropodomorphs. Furthermore, many other characters that are more traditionally associated with only one or two dinosauriform groups were found to have a wider and/or more complex distribution than other studies have previously proposed, e.g. a mediolaterally oriented scar on the anterior face of the distal femur -present in Dromomeron (Nesbitt et al. 2009a), is also found in some herrerasaurids (PVSJ 373). We tried, as objectively as possible, to capture all these similarities, as well as notable differences, between the basal members of each of the major dinosaurian lineages using our newly composed set of characters.Critically, a large number of character states were found to be present in ornithischians and theropods only (see below). Additionally, a number of other character states were found that are present only in sauropodomorphs and herrerasaurids. Some previously proposed dinosaur synapomorphies were also found to be absent from a few important early dinosaur taxa. In most of these cases, our finds changed the optimisations of important characters within the tree, often leading to changes in the structure of the tree itself, as well as our interpretation of the basal dinosaur interrelationships that the distributions of these character states imply.A number of novel clades were recovered by our analysis. Of these, Ornithoscelida is the most strikingly different from previous systems of grouping and classification. A full list of synapomorphies for each of the major clades that we have recovered is given later in this Supplement (Section 3.4). A discussion of a few of the other important finds of our analysis follows here.A constraint tree was also produced in TNT 1.5-beta in order to test how man...

show abstract

“…The main sources of our characters were Gauthier (1986), Sereno (1991), Langer and Benton (2006), Yates (2007), Butler et al (2008), , Nesbitt (2011) and Pol et al (2011).…”

Section: Further Discussion Of the Main Phylogenetic Analysesmentioning

confidence: 99%

A new hypothesis of dinosaur relationships and early dinosaur evolution

Baron

Norman

Barrett

2017

Nature

Self Cite

229

305

View full text Add to dashboard Cite

show abstract

“…This fauna includes the basal ornithischians Lesothosaurus (Thulborn, 1970a(Thulborn, , 1971(Thulborn, , 1972Galton, 1978;Sereno, 1991b;Butler, 2005) and Stormbergia (Butler, 2005), and five named monospecific genera of heterodontosaurids (Heterodontosaurus, Abrictosaurus, Lycorhinus, Lanasaurus, Geranosaurus : Broom, 1911;Haughton, 1924;Crompton and Charig, 1962;Thulborn, 1970bThulborn, , 1974; Table 2 A list of Late Triassic taxa that were once thought to represent ornithischian dinosaurs, but are now regarded as belonging to other reptilian clades. Taxa erroneously thought to be dinosaurs, but not ornithischians, are listed in Table 3 Gow, 1975;Hopson, 1975;Santa Luca et al, 1976;Santa Luca, 1980;Gow, 1990;Butler et al, 2008b). Recent reviews consider only three of the heterodontosaurid genera to be valid (Weishampel and Witmer, 1990;Norman et al, 2004c).…”

Section: Early Jurassic Ornithischians -Fossil Record and Distributionmentioning

confidence: 99%

“…Several large-scale analyses of archosaur and dinosaur phylogeny are underway (e.g., Brusatte et al, 2008c;Nesbitt et al, 2009bNesbitt et al, , 2010Brusatte et al, 2010b;SJN, unpublished data;RBI, unpublished data), and paleontologists are just beginning to experiment with large phylogenetic datasets. These analyses will be instrumental in reconstructing the pattern of anatomical character change on the line to dinosaurs (e.g., Nesbitt et al, 2009a,b), as well as the biogeographic distribution of dinosaurs during the Triassic and Jurassic (e.g., Upchurch et al, 2002;Butler et al, 2006b;Nesbitt et al, 2009b).…”

Section: The Evolutionary Radiation Of Dinosaurs: Future Directionsmentioning

confidence: 99%

The origin and early radiation of dinosaurs

Brusatte

Nesbitt

Irmis

et al. 2010

Earth-Science Reviews

Self Cite

236

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

“…Fieldwork lead by the Denver Museum of Nature & Science in the Lower Cretaceous Cedar Mountain Formation of eastern Utah, USA, has produced several taxonomically distinct iguanodont (sensu Butler et al 2008) specimens at different stratigraphic levels. The Cedar Mountain Formation (Valangian?…”

Section: Introductionmentioning

confidence: 99%

Early and Middle Cretaceous Iguanodonts in Time and Space

Carpenter¹,

Ishida²

2010

J. iber. geol.

View full text Add to dashboard Cite

Iguanodontes del Cretácico temprano y "medio" en el tiempo y en el espacio Abstract Recent discoveries of diverse iguanodonts throughout the Cedar Mountain Formation (Utah, USA) have led us to assess the global diversity of Early Cretaceous iguanodonts. The record in England is more diverse than previously recognized due to Iguanodon being a wastebasket genus throughout the Twentieth Century. Several new taxa, previously recognized as generically distinct by Harry Grovier Seeley, are named. The spatial and temporal distributions of iguanodonts are plotted on global maps as a key to understanding the origin of the Cedar Mountain Formation iguanodonts. Keywords: Early Cretaceous, Iguanodonts, Dinosauria ResumenLos recientes descubrimientos de diversos iguanodontes en la Formación Cedar Mountain (Utah, EE.UU.) nos han llevado a valorar la diversidad global de los iguanodontes del Cretácico temprano. El registro en Inglaterra es más diverso de lo que previamente se ha reconocido, debido a que Iguanodon ha sido tratado como un género "cajón de sastre" a lo largo de todo el siglo XX. Varios de los nuevos taxones, previamente reconocidos como genéricamente distintos por Harry Seeley Grovier, se denominan. La distribución espacial y temporal de Iguanodontia se superponen sobre mapas globales como una clave para comprender el origen de los iguanodontes de la Formación Cedar Mountain.

show abstract

The phylogeny of the ornithischian dinosaurs

Cited by 265 publications

References 102 publications

A new hypothesis of dinosaur relationships and early dinosaur evolution

A new hypothesis of dinosaur relationships and early dinosaur evolution

The origin and early radiation of dinosaurs

Early and Middle Cretaceous Iguanodonts in Time and Space

Contact Info

Product

Resources

About

The phylogeny of the ornithischian dinosaurs

Cited by 265 publications

References 102 publications

A new hypothesis of dinosaur relationships and early dinosaur evolution

A new hypothesis of dinosaur relationships and early dinosaur evolution

The origin and early radiation of dinosaurs

Early and Middle Cretaceous Iguanodonts in Time and Space

Contact Info

Product

Resources

About

Early and Middle Cretaceous Iguanodonts in Time and Space