Timeline of ornithomimosaur research

Last updated

Skeleton of Ornithomimus edmontonicus Ornithomimus edmontonicus.jpg
Skeleton of Ornithomimus edmontonicus

This timeline of ornithomimosaur research is a chronological listing of events in the history of paleontology focused on the ornithomimosaurs, a group of bird-like theropods popularly known as the ostrich dinosaurs. Although fragmentary, probable, ornithomimosaur fossils had been described as far back as the 1860s, [1] the first ornithomimosaur to be recognized as belonging to a new family distinct from other theropods was Ornithomimus velox , described by Othniel Charles Marsh in 1890. [2] Thus the ornithomimid ornithomimosaurs were one of the first major Mesozoic theropod groups to be recognized in the fossil record. [3] The description of a second ornithomimosaur genus did not happen until nearly 30 years later, when Henry Fairfield Osborn described Struthiomimus in 1917. [2] Later in the 20th century, significant ornithomimosaur discoveries began occurring in Asia. The first was a bonebed of "Ornithomimus" (now Archaeornithomimus ) asiaticus found at Iren Debasu. [3] More Asian discoveries took place even later in the 20th century, including the disembodied arms of Deinocheirus mirificus and the new genus Gallimimus bullatus . [3] The formal naming of the Ornithomimosauria itself was performed by Rinchen Barsbold in 1976. [2]


Early research into ornithomimosaur evolution was based on comparative anatomy. [2] In 1972, Dale Russell argued that the Jurassic Elaphrosaurus of Africa was an ancestral relative of ornithomimids. The descriptions of Garudimimus and Harpymimus in the 1980s revealed the existence of primitive ornithomimosaurs outside of the Ornithomimidae proper. [3] Subsequent research and discoveries during the 1990s refined science's knowledge of ornithomimosaur evolution. [2] In 1994, Pelecanimimus polyodon was described from Europe, the first known ornithomimosaur from that continent and apparently a very evolutionarily primitive taxon. From the late 1990s into the early 21st century cladistic evidence mounted against Russell's hypothesis that ornithomimosaurs were descended from a close relative of Elaphrosaurus, and favored an ancestry close to Pelecanimimus. Paleontologists found that within the theropod family tree, ornithomimosaurs were primitive coelurosaurs closely related to, but outside of, the maniraptorans. [3]

The juxtaposition of apparent evolutionary affinities to carnivorous dinosaurs with the possession of toothless beaks has led to controversy among paleontologists trying to reconstruct the diet of ornithomimosaurs. Osborn hypothesized in 1917 that ornithomimosaurs may have eaten plants, social insects, or aquatic invertebrates. In the 1970s paleontologists Russell, Halszka Osmolska, and her colleagues considered ornithomimosaurs carnivores that may have fed on insects, small vertebrates, or eggs. In the early to mid 1980s, however Russell and Elizabeth Nicholls began advocating a reinterpretation of ornithomimosaurs as herbivores. With the 1999 report of gastroliths in the new genus Sinornithomimus , came further support for reinterpreting ornithomimosaurs as herbivores or filter feeders rather than carnivores. [4] In 2001, Mark Norell reported a comb-like structure in the beak of Gallimimus that may have been used for filter feeding, bringing renewed credibility to one of Osborn's 1917 hypotheses. If this interpretation of the evidence is correct, Gallimimus would be the largest terrestrial filter feeder in history. [5]

19th century

Holotype material of Ornithomimus velox Ornithomimus velox.jpg
Holotype material of Ornithomimus velox






20th century

Cast of a Struthiomimus altus skeleton at the Royal Ontario Museum Struthiomimus ROM.jpg
Cast of a Struthiomimus altus skeleton at the Royal Ontario Museum




An early restoration of S. altus published in a 1921 issue of the magazine Natural History Struthiomimus.jpg
An early restoration of S. altus published in a 1921 issue of the magazine Natural History







Skeletal mount of "Ornithmomimus" (now Archaeornithomimus) asiaticus ArchaeornithomimusAsiaticus-PaleozoologicalMuseumOfChina-May23-08.jpg
Skeletal mount of "Ornithmomimus" (now Archaeornithomimus ) asiaticus






Holotype of Deinocheirus mirificus on display Deinocheirusbcn.JPG
Holotype of Deinocheirus mirificus on display



Life restoration of Gallimimus Gallimimus Steveoc86.jpg
Life restoration of Gallimimus






Artistic restoration of Harpymimus okladnikovi Harpymimus steveoc.jpg
Artistic restoration of Harpymimus okladnikovi




The beaks of ornithomimosaurs had deeper tips than ratites like the skull this ostrich. The Childrens Museum of Indianapolis - Ostrich skull.jpg
The beaks of ornithomimosaurs had deeper tips than ratites like the skull this ostrich.




Estimated size of Pelecanimimus, compared to a human Pelecanimimus SIZE.png
Estimated size of Pelecanimimus , compared to a human
The femur of Timimus Timimus.tif
The femur of Timimus





Artistic restoration of Elaphrosaurus bambergii. Elaphrosaurus.jpg
Artistic restoration of Elaphrosaurus bambergii .


21st century

Skull of Gallimimus Gallimimus bullatus skull.JPG
Skull of Gallimimus




Sinornithomimus Sinornithomimus.jpg





Skeletal mount of Beishanlong Skeleton of Beishanlong grandis.JPG
Skeletal mount of Beishanlong




Artist's restoration of Deinocheirus Hypothetical Deinocheirus.jpg
Artist's restoration of Deinocheirus
Artist's restoration of Tototlmimus Saltillomimus rapidus.jpg
Artist's restoration of Tototlmimus









See also


  1. 1 2 3 4 5 6 7 8 Makovicky, Kobayashi, and Currie (2004); "Table 6.1: Ornithomimosauria", page 139.
  2. 1 2 3 4 5 6 Makovicky, Kobayashi, and Currie (2004); "Introduction", page 137.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Makovicky, Kobayashi, and Currie (2004); "Systematics and Evolution", page 146.
  4. 1 2 3 4 5 6 7 8 9 10 Makovicky, Kobayashi, and Currie (2004); "Paleobiology", page 149.
  5. Makovicky, Kobayashi, and Currie (2004); "Paleobiology", pages 149-150.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Makovicky, Kobayashi, and Currie (2004); "Table 6.1: Ornithomimosauria", page 138.
  7. 1 2 3 4 Makovicky, Kobayashi, and Currie (2004); "Systematics and Evolution", page 147.
  8. 1 2 3 4 5 6 7 8 Makovicky, Kobayashi, and Currie (2004); "Paleobiology", page 150.
  9. For date, see Khan (2014). For expedition, see Lee et al. (2014); "Abstract," page 257.
  10. 1 2 3 4 5 Makovicky, Kobayashi, and Currie (2004); "Systematics and Evolution", page 148.
  11. Makovicky, Kobayashi, and Currie (2004); "Biogeography", page 149.
  12. 1 2 Hurum (2001); "Abstract," page 34.
  13. Hurum (2001); "Abstract," page 35.
  14. Hurum (2001); "Conclusions," page 40.
  15. 1 2 For date and catalogue number, see Lee et al. (2014); "Abstract," page 257. For expedition, see Hecht (2014).
  16. 1 2 Khan (2014).
  17. Buffetaut, Suteethorn, and Tong (2009); "Abstract", page 229.
  18. Makovicky et al. (2010); "Abstract", page 191.
  19. 1 2 3 Hecht (2014); "Fossil smugglers".
  20. Joyce (2014).
  21. Jiji (2014).
  22. Xu et al. (2011); "Abstract", page 213.
  23. Jin, Chen, and Godefroit (2012); "Abstract", page 467.
  24. Lee et al. (2014); "Abstract," page 257.
  25. V.R. Alifanov; S.V. Saveliev (2015). "The Most Ancient Ornithomimosaur (Theropoda, Dinosauria), with Cover Imprints from the Upper Jurassic of Russia". Paleontologicheskii Zhurnal. 49 (6): 71–85. doi:10.1134/S0031030115060039. S2CID   131199807.
  26. ReBecca K. Hunt; James H. Quinn (2018). "A new ornithomimosaur from the Lower Cretaceous Trinity Group of Arkansas". Journal of Vertebrate Paleontology. 38 (1): e1421209. Bibcode:2018JVPal..38E1209H. doi:10.1080/02724634.2017.1421209. S2CID   90165402.
  27. Ian Macdonald; Philip J. Currie (2019). "Description of a partial Dromiceiomimus (Dinosauria: Theropoda) skeleton with comments on the validity of the genus". Canadian Journal of Earth Sciences. 56 (2): 129–157. Bibcode:2019CaJES..56..129M. doi:10.1139/cjes-2018-0162. S2CID   134730129.
  28. Serrano-Brañas, C.I.; Espinosa-Cha´vez, B.; Maccracken, S.A.; Gutie´rrez-Blando, C.; de Leo´n-Da´ vila, C.; Ventura, J.F. (2020). "Paraxenisaurus normalensis, a large deinocheirid ornithomimosaur from the Cerro del Pueblo Formation (Upper Cretaceous), Coahuila, Mexico". Journal of South American Earth Sciences. 101: 102610. Bibcode:2020JSAES.10102610S. doi:10.1016/j.jsames.2020.102610. S2CID   218968100.
  29. Tsogtbaatar, C.; Cullen, T.; Phillips, G.; Rolke, R.; Zanno, L.E. (2022). "Large-bodied ornithomimosaurs inhabited Appalachia during the Late Cretaceous of North America". PLOS ONE. 17 (10): e0266648. Bibcode:2022PLoSO..1766648T. doi: 10.1371/journal.pone.0266648 . PMC   9581415 . PMID   36260601.
  30. Rachel E. Nottrodt (2022). "First articulated ornithomimid specimens from the upper Maastrichtian Scollard Formation of Alberta, Canada". Journal of Vertebrate Paleontology. 41 (5). doi:10.1080/02724634.2021.2019754. S2CID   247311332.
  31. Allain, R.; Vullo, R.; Phillips, G.; Rolke, R.; Bourgeais,R.; Bourgeais,R.; Goedert, J.; Anquintin, J.; Lasseron, M.; Vullo, R.; Martin, J. E.; Perez-Garcia,A.; Peyre de Fabregues, C.; Royo-Torres, R.; Augier, D.; Bailly, G.; Cazes, L.; Despresy, Y.; Galliegue, A.; Gomez,B.; Goussard, F.; Lenglet, T.; Vacant, R.; Mazan; Tour-nepiche, J.-F. (2022). "Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): Implications for continental faunal turnover at the J/K boundary". Geodiversitas. 44 (25): 683–752. doi:10.5252/geodiversitas2022v44a25. S2CID   251106920.

Related Research Articles

<i>Gallimimus</i> Ornithomimid dinosaur genus from the Late Cretaceous Period

Gallimimus is a genus of theropod dinosaur that lived in what is now Mongolia during the Late Cretaceous period, about seventy million years ago (mya). Several fossils in various stages of growth were discovered by Polish-Mongolian expeditions in the Gobi Desert of Mongolia during the 1960s; a large skeleton discovered in this region was made the holotype specimen of the new genus and species Gallimimus bullatus in 1972. The generic name means "chicken mimic", referring to the similarities between its neck vertebrae and those of the Galliformes. The specific name is derived from bulla, a golden capsule worn by Roman youth, in reference to a bulbous structure at the base of the skull of Gallimimus. At the time it was named, the fossils of Gallimimus represented the most complete and best preserved ornithomimid material yet discovered, and the genus remains one of the best known members of the group.

<i>Anserimimus</i> Extinct genus of dinosaurs

Anserimimus is a genus of ornithomimid theropod dinosaur, from the Late Cretaceous Period of what is now Mongolia. It was a lanky, fast-running animal, possibly an omnivore. From what fossils are known, it probably closely resembled other ornithomimids, except for its more powerful forelimbs.

<span class="mw-page-title-main">Ornithomimosauria</span> Extinct clade of theropod dinosaurs

Ornithomimosauria are theropod dinosaurs which bore a superficial resemblance to the modern-day ostrich. They were fast, omnivorous or herbivorous dinosaurs from the Cretaceous Period of Laurasia, as well as Africa and possibly Australia. The group first appeared in the Early Cretaceous and persisted until the Late Cretaceous. Primitive members of the group include Nqwebasaurus, Pelecanimimus, Shenzhousaurus, Hexing and Deinocheirus, the arms of which reached 2.4 m (8 feet) in length. More advanced species, members of the family Ornithomimidae, include Gallimimus, Struthiomimus, and Ornithomimus. Some paleontologists, like Paul Sereno, consider the enigmatic alvarezsaurids to be close relatives of the ornithomimosaurs and place them together in the superfamily Ornithomimoidea.

<i>Struthiomimus</i> Extinct genus of reptile

Struthiomimus is a genus of ornithomimid dinosaurs from the late Cretaceous of North America. Ornithomimids were long-legged, bipedal, ostrich-like dinosaurs with toothless beaks. The type species, Struthiomimus altus, is one of the more common small dinosaurs found in Dinosaur Provincial Park; its abundance suggests that these animals were herbivores or omnivores rather than pure carnivores.

<i>Ornithomimus</i> Ornithomimid dinosaur genus from the Late Cretaceous Period

Ornithomimus is a genus of ornithomimid theropod dinosaurs from the Campanian and Maastrichtian ages of Late Cretaceous Western North America. Ornithomimus was a swift, bipedal dinosaur which fossil evidence indicates was covered in feathers and equipped with a small toothless beak that may indicate an omnivorous diet. It is usually classified into two species: the type species, Ornithomimus velox, and a referred species, Ornithomimus edmontonicus. O. velox was named in 1890 by Othniel Charles Marsh on the basis of a foot and partial hand from the Denver Formation of Colorado. Another seventeen species have been named since then, though almost all of them have been subsequently assigned to new genera or shown to be not directly related to Ornithomimus velox. The best material of species still considered part of the genus has been found in Alberta, representing the species O. edmontonicus, known from several skeletons from the Horseshoe Canyon Formation. Additional species and specimens from other formations are sometimes classified as Ornithomimus, such as Ornithomimus samueli from the earlier Dinosaur Park Formation.

<i>Dromiceiomimus</i> Extinct genus of reptiles

Dromiceiomimus is a genus of ornithomimid theropod from the Late Cretaceous of Alberta, Canada. The type species, D. brevitertius, is considered a synonym of Ornithomimus edmontonicus by some authors, while others consider it a distinct and valid taxon.

<i>Deinocheirus</i> Genus of theropod dinosaurs

Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.

<i>Garudimimus</i> Ornithomimosaur genus from the Late Cretaceous

Garudimimus is a genus of ornithomimosaur that lived in Asia during the Late Cretaceous. The genus is known from a single specimen found in 1981 by a Soviet-Mongolian paleontological expedition in the Bayan Shireh Formation and formally described in the same year by Rinchen Barsbold; the only species is Garudimimus brevipes. Several interpretations about the anatomical traits of Garudimimus were made in posterior examinations of the specimen, but most of them were criticized during its comprehensive redescription in 2005. Extensive undescribed ornithomimosaur remains at the type locality of Garudimimus may represent additional specimens of the genus.

<i>Archaeornithomimus</i> Extinct genus of dinosaurs

Archaeornithomimus is a genus of ornithomimosaurian theropod dinosaur that lived in Asia during the Late Cretaceous period, around 96 million years ago in the Iren Dabasu Formation.

<i>Pelecanimimus</i> Extinct genus of dinosaurs

Pelecanimimus is an extinct genus of basal ("primitive") ornithomimosaurian dinosaur from the Early Cretaceous of Spain. It is notable for possessing more teeth than any other member of the Ornithomimosauria, most of which were toothless.

<span class="mw-page-title-main">Ornithomimidae</span> Group of theropod dinosaurs

Ornithomimidae is a family of theropod dinosaurs which bore a superficial resemblance to modern ostriches. Ornithomimids were fast, omnivorous or herbivorous dinosaurs known mainly from the Late Cretaceous Period of Laurasia, though they have also been reported from the Lower Cretaceous Wonthaggi Formation of Australia.

<i>Shenzhousaurus</i> Extinct genus of reptiles

Shenzhousaurus is a genus of basal ornithomimosaur from the Lower Cretaceous of China.

<i>Nqwebasaurus</i> Extinct genus of dinosaur

Nqwebasaurus is a basal coelurosaur and is the basal-most member of the coelurosaurian clade Ornithomimosauria from the Early Cretaceous of South Africa. The name Nqwebasaurus is derived from the Xhosa word "Nqweba" which is the local name for the Kirkwood district, and "thwazi" is ancient Xhosa for "fast runner". Currently it is the oldest coelurosaur in Africa and shows that basal coelurosaurian dinosaurs inhabited Gondwana 50 million years earlier than previously thought. The type specimen of Nqwebasaurus was discovered by William J. de Klerk who is affiliated with the Albany Museum in Grahamstown. It is the only fossil of its species found to date and was found in the Kirkwood Formation of the Uitenhage Group. Nqwebasaurus has the unofficial nickname "Kirky", due to being found in the Kirkwood.

<span class="mw-page-title-main">Nemegt Formation</span> Geological formation in Mongolia

The Nemegt Formation is a geological formation in the Gobi Desert of Mongolia, dating to the Late Cretaceous. The formation consists of river channel sediments and contains fossils of fish, turtles, crocodilians, and a diverse fauna of dinosaurs, including birds.

<span class="mw-page-title-main">Deinocheiridae</span> Extinct family of dinosaurs

Deinocheiridae is a family of ornithomimosaurian dinosaurs, living in Asia and the Americas from the Albian until the Maastrichtian. The family was originally named by Halszka Osmólska and Roniewicz in 1970, including only the type genus Deinocheirus. In a 2014 study by Yuong-Nam Lee and colleagues and published in the journal Nature, it was found that Deinocheiridae was a valid family. Lee et al. found that based on a new phylogenetic analysis including the recently discovered complete skeletons of Deinocheirus, the type genus, as well as Garudimimus and Beishanlong, could be placed as a successive group, with Beishanlong as the most primitive and Deinocheirus as most derived. The family Garudimimidae, named in 1981 by Rinchen Barsbold, is now a junior synonym of Deinocheiridae as the latter family includes the type genus of the former. The group existed from 115 to 69 million years ago, with Beishanlong living from 115 to 100 mya, Garudimimus living from 98 to 83 mya, and Deinocheirus living from 71 to 69 mya. Other genera included are Paraxenisaurus, and possibly Harpymimus and Hexing.

<i>Beishanlong</i> Extinct genus of dinosaurs

Beishanlong is a genus of giant ornithomimosaurian theropod dinosaur from the Early Cretaceous of China. It is the second-largest ornithomimosaur discovered, only surpassed by Deinocheirus.

<span class="mw-page-title-main">Timeline of troodontid research</span> Events in the history of paleontology

This timeline of troodontid research is a chronological listing of events in the history of paleontology focused on the troodontids, a group of bird-like theropod dinosaurs including animals like Troodon. Troodontid remains were among the first dinosaur fossils to be reported from North America after paleontologists began performing research on the continent, specifically the genus Troodon itself. Since the type specimen of this genus was only a tooth and Troodon teeth are unusually similar to those of the unrelated thick-headed pachycephalosaurs, Troodon and its relatives would be embroiled in taxonomic confusion for over a century. Troodon was finally recognized as distinct from the pachycephalosaurs by Phil Currie in 1987. By that time many other species now recognized as troodontid had been discovered but had been classified in the family Saurornithoididae. Since these families were the same but the Troodontidae named first, it carries scientific legitimacy.

<span class="mw-page-title-main">Timeline of oviraptorosaur research</span>

This timeline of oviraptorosaur research is a chronological listing of events in the history of paleontology focused on the oviraptorosaurs, a group of beaked, bird-like theropod dinosaurs. The early history of oviraptorosaur paleontology is characterized by taxonomic confusion due to the unusual characteristics of these dinosaurs. When initially described in 1924 Oviraptor itself was thought to be a member of the Ornithomimidae, popularly known as the "ostrich" dinosaurs, because both taxa share toothless beaks. Early caenagnathid oviraptorosaur discoveries like Caenagnathus itself were also incorrectly classified at the time, having been misidentified as birds.

<i>Aepyornithomimus</i> Extinct genus of dinosaurs

Aepyornithomimus is a genus of ornithomimid theropod dinosaur from the Late Cretaceous Djadokhta Formation in Mongolia. It lived in the Campanian, around 75 million years ago, when the area is thought to have been a desert. The type and only species is A. tugrikinensis.

<i>Afromimus</i> Extinct genus of dinosaurs

Afromimus is a genus of theropod dinosaur from the Early Cretaceous Elrhaz Formation of Niger. It contains a single species, A. tenerensis, named in 2017 by Paul Sereno from parts of the right leg, vertebrae, and ribs found in the Ténéré Desert. It was originally classified as an ornithomimosaurian, but subsequently it was argued to be an abelisauroid.