His doctoral dissertation was on sauropod evolution and phylogeny, and he has continued this work in cladistic analysis and revision of the group (see e.g. Wilson and Sereno 1994, 1998, Wilson 2005b, and especially Wilson 2002). With Paul Sereno, he defined the cladesMacronaria and Somphospondyli (Wilson & Sereno 1998).
Wilson was also involved in the discovery and description of Pabwehshi pakistanensis, the first discovery of decent (diagnostic) Cretaceouscrocodylian fossil remains from the Indian subcontinent, in the discovery of Rajasaurus narmadensis, the most completely known theropod dinosaur from India and a member of the family Abelisauridae, description of a number of North African dinosaurs (theropods and sauropods) from Niger, and rediscriptions of the Cretaceous sauropods Titanosaurus colberti (as Isisaurus) and Nemegtosaurus (previously thought to be a diplodocoid, but now recognised as a titanosaur).
Wilson, J. A. and Sereno, P. C. (1994) Higher-level phylogeny of sauropod dinosaurs. Journal of Vertebrate Paleontology, Supplement 14:52A.
Wilson, J.A. & Sereno, P.C. (1998). Early evolution and Higher-level phylogeny of sauropod dinosaurs. Society of Vertebrate Paleontology, Memoir 5, 1-68. (includes definitions of the clades Macronaria and Somphospondyli)
Sereno, P. C., Beck, A.L., Dutheil, D.B., Gado, B., Larsson, H.C.E., Lyon, G.H., Marcot, J. D., Rauhut, O. W. M., Sadleir, R.W., Sidor, C.A., Varricchio, D.J., Wilson, G. P. & Wilson, J. A. 1998. A long-snouted predatory dinosaur from Africa and the evolution of spinosaurids. Science 282:1298-1302. document in pdf format (description of Suchomimus, and spinosaur relationships)
Wilson, J. A. and M. T. Carrano, (1999). Titanosaurs and the origin of 'wide-gauge' trackways: a biomechanical and systematic perspective on sauropod locomotion. Paleobiology 25:252-267. (Titanosaurs had a different gait to earlier sauropods - the legs are spaced further apart, may have facilitated tripodal feeding)
Wilson, J. A., R. N. Martinez & O. Alcober. (1999). Distal tail segment of a titanosaur (Dinosauria: Sauropoda) from the Upper Cretaceous of Mendoza, Argentina. Journal of Vertebrate Paleontology 19:591-594.
Wilson, J A. (1999). A nomenclature for vertebral laminae in sauropods and other saurischian dinosaurs. Journal of Vertebrate Paleontology 19(4):639-653. (vertebral laminae can play an important role in sauropod classification)
Wilson, J.A. (1999) The evolution and phylogeny of sauropod dinosaurs. Ph.D. dissertation, University of Chicago, 384pp [in 2 vols.]
Sereno, P.C., Beck, A.L., Dutheil, D.B., Larsson, H.C.E., Lyon, G.H., Moussa, B., Sadleir, R.W., Sidor, C.A., Varricchio, D.J., Wilson, G. P. & Wilson, J. A., (1999), Cretaceous Sauropods from the Sahara and the Uneven Rate of Skeletal Evolution Among Dinosaurs, Science 286(5443): 1342-1347 (Nov 12 1999) (describes two new African sauropods: Jobaria tiguidensis, a late persisting primitive sauropod, and Nigersaurus taqueti, a Rebbachisaur))
Wilson, J.A., Malkani, M.S., and Gingerich, P.D. (2001) New crocodyliform (Reptilia, Mesoeucrocodylia) from the Upper Cretaceous Pab Formation of Vitakri, Balochistan (Pakistan). Contributions from the Museum of Paleontology, University of Michigan 30(12): 321–336. (on Pabwehshi pakistanensis)
Wilson, J.A. (2002) Sauropod dinosaur phylogeny: critique and cladistic analysis, Zoological Journal of the Linnean Society 136(2):215-275 (a detailed cladistic analysis of sauropod phylogeny)
Wilson, J.A. and Upchurch, P (2003) A revision of Titanosaurus Lydekker (Dinosauria-Sauropoda), the first dinosaur genus with a "Gondwanan" distribution, Journal of Systematic Palaeontology Volume 1 Issue 3 - September 2003 (a revision of 14 species of the genus Titanosaurus shows that only five of these are valid. The type speciesT. indicus is considered a nomen dubium, and therefore the abandonment of suprageneric taxa based on it - e.g. Titanosaurinae, Titanosauridae, and Titanosauroidea - is suggested. The species T. colberti is renamed Isisaurus colberti)
Wilson, J.A., Sereno, P.C., Srivastava, S., Bhatt, D.K., Khosla, A. and Sahni, A. (2003) A new abelisaurid (Dinosauria, Theropoda) from the Lameta Formation (Cretaceous, Maastrichtian) of India. Contributions from the Museum of Paleontology, University of Michigan 31(1):1-42 (description of Rajasaurus narmadensis)
Wilson, J.A. (2005). Redescription of the Mongolian sauropod Nemegtosaurus mongoliensis Nowinski (Dinosauria: Saurischia) and comments on Late Cretaceous sauropod diversity. Journal of Systematic Palaeontology 3: 283–318. (shows that Nemegtosaurus and Quaesitosaurus are closely related and belong to the titanosaur group, rather than the diplodocoidea; redefines the family Nemegtosauridae. See New Nemegtosaurus paperArchived 2016-03-03 at the Wayback Machine for more.
Wilson, J.A. (2005b) "Overview of Sauropod Phylogeny and Evolution", in The Sauropods: Evolution and Paleobiology (broad overview of phylogenetic characteristics and evolution development of the main sauropod clades, also phylocode-style definitions for each clade.
Wilson, J. A. and Sereno, P. C. (2005) "Structure and Evolution of a Sauropod Tooth Battery" in The Sauropods: Evolution and Paleobiology (Nigersaurus skull and dentition, illustrating Rebbachisaur feeding adaptations)
Titanosaurs were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thriving at the time of the extinction event at the end of the Cretaceous. This group includes some of the largest land animals known to have ever existed, such as Patagotitan—estimated at 37 m (121 ft) long with a weight of 69 tonnes —and the comparably-sized Argentinosaurus and Puertasaurus from the same region.
Nemegtosauridae is a family of titanosaurian sauropod dinosaurs based on their diplodocid-like skulls. Only three species are known: Nemegtosaurus, Quaesitosaurus and possibly Tapuiasaurus, each from the Cretaceous.
Titanosaurus is a dubious genus of sauropod dinosaurs, first described by Richard Lydekker in 1877. It is known from the Maastrichtian Lameta Formation of India.
Antarctosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. The type species, Antarctosaurus wichmannianus, and a second species, Antarctosaurus giganteus, were described by prolific German paleontologist Friedrich von Huene in 1929. Three additional species of Antarctosaurus have been named since then but later studies have considered them dubious or unlikely to pertain to the genus.
Jainosaurus is a genus of titanosaurian sauropod dinosaur of India and wider Asia, which lived in the Maastrichtian. No accurate estimate of the length, height, or weight has yet been made. The humerus of the type specimen is 134 centimetres long.
Alamosaurus is a genus of opisthocoelicaudiine titanosaurian sauropod dinosaurs containing a single known species, Alamosaurus sanjuanensis, from the Maastrichtian age of the Late Cretaceous period in what is now southwestern North America. Isolated vertebrae and limb bones indicate that it reached sizes comparable to Argentinosaurus and Puertasaurus, which would make it the absolute largest dinosaur known from North America. Its fossils have been recovered from a variety of rock formations spanning the Maastrichtian age. Specimens of a juvenile Alamosaurus sanjuanensis have been recovered from only a few meters below the Cretaceous-Paleogene boundary in Texas, making it among the last surviving non-avian dinosaur species. Alamosaurus is the only known sauropod to have inhabited North America after their nearly 30-million year absence from the North American fossil record and probably represents an immigrant from South America.
Agustinia is a genus of sauropod dinosaur from the Early Cretaceous of South America. The genus contains a single species, Agustinia ligabuei, known from a single specimen that was recovered from the Lohan Cura Formation of Neuquén Province in Argentina. It lived about 116–108 million years ago, in the Aptian–Albian stages of the Early Cretaceous Period.
Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located. Fossil evidence suggests that macronarian dinosaurs lived from the Middle Jurassic (Bathonian) through the Late Cretaceous (Maastrichtian). Macronarians have been found globally, including discoveries in Argentina, the United States, Portugal, China, and Tanzania. Like other sauropods, they are known to have inhabited primarily terrestrial areas, and little evidence exists to suggest that they spent much time in coastal environments. Macronarians are diagnosed through their distinct characters on their skulls, as well as appendicular and vertebral characters. Macronaria is composed of several subclades and families notably including Camarasauridae and Titanosauriformes, among several others. Titanosauriforms are particularly well known for being some of the largest terrestrial animals to ever exist.
Opisthocoelicaudia is a genus of sauropod dinosaur of the Late Cretaceous Period discovered in the Gobi Desert of Mongolia. The type species is Opisthocoelicaudia skarzynskii. A well-preserved skeleton lacking only the head and neck was unearthed in 1965 by Polish and Mongolian scientists, making Opisthocoelicaudia one of the best known sauropods from the Late Cretaceous. Tooth marks on this skeleton indicate that large carnivorous dinosaurs had fed on the carcass and possibly had carried away the now-missing parts. To date, only two additional, much less complete specimens are known, including part of a shoulder and a fragmentary tail. A relatively small sauropod, Opisthocoelicaudia measured about 11.4–13 m (37–43 ft) in length. Like other sauropods, it would have been characterised by a small head sitting on a very long neck and a barrel shaped trunk carried by four column-like legs. The name Opisthocoelicaudia means "posterior cavity tail", alluding to the unusual, opisthocoel condition of the anterior tail vertebrae that were concave on their posterior sides. This and other skeletal features lead researchers to propose that Opisthocoelicaudia was able to rear on its hindlegs.
Rebbachisauridae is a family of sauropod dinosaurs known from fragmentary fossil remains from the Cretaceous of South America, Africa, North America, Europe and possibly Central Asia.
Isisaurus is a genus of titanosaurian dinosaur from the Late Cretaceous Lameta Formation of India and Pab Formation of Pakistan. The genus contains a single species, Isisaurus colberti.
Gobititan is a genus of herbivorous sauropod dinosaur from the Aptian faunal stage of the Early Cretaceous. The name of this genus is derived from the Gobi desert region and the Titans of Greek mythology, which is a reference to its large body size. The specific name shenzhouensis, is derived from "Shenzhou", an ancient name for China.
Saltasauridae is a family of armored herbivorous sauropods from the Upper Cretaceous. They are known from fossils found in South America, Asia, North America, and Europe. They are characterized by their vertebrae and feet, which are similar to those of Saltasaurus, the first of the group to be discovered and the source of the name. The last and largest of the group and only one found in North America, Alamosaurus, was thirty-four metres in length and one of the last sauropods to go extinct.
Neosauropoda is a clade within Dinosauria, coined in 1986 by Argentine paleontologist José Bonaparte and currently described as Saltasaurus loricatus, Diplodocus longus, and all animals directly descended from their most recent common ancestor. The group is composed of two subgroups: Diplodocoidea and Macronaria. Arising in the early Jurassic and persisting until the Cretaceous-Paleogene extinction event, Neosauropoda contains the majority of sauropod genera, including genera such as Apatosaurus, Brachiosaurus, and Diplodocus. It also includes giants such as Argentinosaurus, Patagotitan and Sauroposeidon, and its members remain the largest land animals ever to have lived.
Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch et al. in 2004 as the most recent common ancestor of Malawisaurus and Saltasaurus and all the descendants of that ancestor. Lithostrotia is derived from the Ancient Greek lithostros, meaning "inlaid with stones", referring to the fact that many known lithostrotians are preserved with osteoderms. However, osteoderms are not a distinguishing feature of the group, as the two noted by Unchurch et al. include caudal vertebrae with strongly concave front faces (procoely), although the farthest vertebrae are not procoelous.
Dongbeititan is a genus of sauropod dinosaur from the Early Cretaceous-age Yixian Formation of Beipiao, Liaoning, China. It is based on holotype DNHM D2867, a partial postcranial skeleton including bones from the limbs, shoulder and pelvic girdles, and vertebrae, which was described in 2007. Its describers suggested it was as a basal titanosauriform, not as derived as Gobititan or Jiutaisaurus, but more derived than Euhelopus, Fusuisaurus, and Huanghetitan. The type species is D. dongi, and it is the first named sauropod from the Yixian Formation, which is part of the well-known Jehol Group. The genus name refers to the region Dongbei and to Greek titan, "giant". The specific name honours the Chinese paleontologist Dong Zhiming. Like other sauropods, Dongbeititan would have been a large quadrupedal herbivore.
Nigersaurus is a genus of rebbachisaurid sauropod dinosaur that lived during the middle Cretaceous period, about 115 to 105 million years ago. It was discovered in the Elrhaz Formation in an area called Gadoufaoua, in Niger. Fossils of this dinosaur were first described in 1976, but it was only named Nigersaurus taqueti in 1999, after further and more complete remains were found and described. The genus name means "Niger reptile", and the specific name honours the palaeontologist Philippe Taquet, who discovered the first remains.
Tapuiasaurus is a genus of titanosaur which lived during the Lower Cretaceous period in what is now Minas Gerais, Brazil. Its fossils, including a partial skeleton with a nearly complete skull, have been recovered from the Quiricó Formation of the São Francisco Basin in Minas Gerais, eastern Brazil. This genus was named by Hussam Zaher, Diego Pol, Alberto B. Carvalho, Paulo M. Nascimento, Claudio Riccomini, Peter Larson, Rubén Juárez Valieri, Ricardo Pires Domingues, Nelson Jorge da Silva Jr. and Diógenes de Almeida Campos in 2011, and the type species is Tapuiasaurus macedoi.
Aeolosaurini is an extinct clade of titanosaurian dinosaurs known from the Cretaceous period of Argentina and Brazil. Rodrigo M. Santucci and Antonio C. de Arruda-Campos (2011) in their cladistic analysis found Aeolosaurus, Gondwanatitan, Maxakalisaurus, Panamericansaurus and Rinconsaurus to be aeolosaurids.
Triunfosaurus is a genus of somphospondylan sauropod dinosaur from the Early Cretaceous of Brazil. It contains a single species, T. leonardii, described by Carvalho et al. in 2017. As a genus, Triunfosaurus can be distinguished from all other titanosaurs by the unique proportions of its ischium. It was initially described as a basal titanosaur, making it the earliest basal titanosaur known; however, subsequent research questioned the identification of the taxon as a titanosaur, instead reassigning it to the Somphospondyli.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
