Timeline of tyrannosaur research

Last updated

Skeletal mount of the Tyrannosaurus holotype. Tyrannosaurus Rex Holotype.jpg
Skeletal mount of the Tyrannosaurus holotype.

This timeline of tyrannosaur research is a chronological listing of events in the history of paleontology focused on the tyrannosaurs, a group of predatory theropod dinosaurs that began as small, long-armed bird-like creatures with elaborate cranial ornamentation but achieved apex predator status during the Late Cretaceous as their arms shrank and body size expanded. Although formally trained scientists did not begin to study tyrannosaur fossils until the mid-19th century, these remains may have been discovered by Native Americans and interpreted through a mythological lens. The Montana Crow tradition about thunder birds with two claws on their feet may have been inspired by isolated tyrannosaurid forelimbs found locally. [1] Other legends possibly inspired by tyrannosaur remains include Cheyenne stories about a mythical creature called the Ahke, [2] and Delaware stories about smoking the bones of ancient monsters to have wishes granted. [3]

Contents

Tyrannosaur remains were among the first dinosaur fossils collected in the United States. The first of these was named Deinodon horridus by Joseph Leidy. However, as this species was based only on teeth the name would fall into disuse. [4] Soon after, Edward Drinker Cope described Laelaps aquilunguis from a partial skeleton in New Jersey. Its discovery heralded the realization that carnivorous dinosaurs were bipeds, unlike the lizardlike megalosaurs sculpted for the Crystal Palace. [5] Laelaps was also among the first dinosaurs to be portrayed artistically as a vigorous, active animal, presaging the Dinosaur Renaissance by decades. [6] Later in the century, Cope's hated rival Othniel Charles Marsh would discover that the name Laelaps had already been given to a parasitic mite, and would rename the dinosaur Dryptosaurus . [7]

Early in the 20th century, Tyrannosaurus itself was discovered by Barnum Brown and named by Henry Fairfield Osborn, who would recognize it as a representative of a distinct family of dinosaurs he called the Tyrannosauridae. [8] Tyrannosaur taxonomy would be controversial for many decades afterward. One controversy centered around the use of the name Tyrannosauridae for this family, as the name "Deinodontidae" had already been proposed. The name Tyrannosauridae came out victorious following arguments put forth by Dale Russell in 1970. [9] The other major controversy regarding tyrannosaur taxonomy was the family's evolutionary relationships. Early in the history of paleontology, it was assumed that the large carnivorous dinosaurs were all part of one evolutionary lineage ("carnosaurs"), while the small carnivorous dinosaurs were part of a separate lineage (coelurosaurs). Tyrannosaurid anatomy led some early researchers like Matthew, Brown, and Huene, to cast doubt on the validity of this division. However, the traditional carnosaur-coelurosaur division persisted until the early 1990s, when the application of cladistics to tyrannosaur systematics confirmed the doubts of early workers and found tyrannosaurs to be large-bodied coelurosaurs. [10]

Another debate about tyrannosaurs would not be settled until the early 21st century: their diet. Early researchers were so overwhelmed by the massive bulk of Tyrannosaurus that some, like Lawrence Lambe, were skeptical that it was even capable of hunting down live prey and assumed that it lived as a scavenger. This view continued to be advocated into the 1990s by Jack Horner but was shown false by Kenneth Carpenter, who reported the discovery of a partially healed tyrannosaur bite wound on an Edmontosaurus annectens tail vertebra, proving that T. rex at least sometimes pursued living victims. [11]

Prescientific

Bones of Dryptosaurus, originally known as Laelaps. DryptosaurusLaelaps.jpg
Bones of Dryptosaurus , originally known as Laelaps .

19th century

Illustration of the teeth of Deinodon. Deinodon.JPG
Illustration of the teeth of Deinodon .

1850s

1856

1860s

Inaccurate reconstructions of "Laelaps aquilunguis" and Elasmosaurus (1869). Laelaps-cope.jpg
Inaccurate reconstructions of " Laelaps aquilunguis " and Elasmosaurus (1869).

1865

1866

1868

1870s

Illustration of the type specimen (AMNH 3982) of Manospondylus gigas Manospondylus.jpg
Illustration of the type specimen (AMNH 3982) of Manospondylus gigas

1876

1877

1880s

1884

1890s

Leaping Laelaps by Charles R. Knight, 1896. Laelaps-Charles Knight-1897.jpg
Leaping Laelaps by Charles R. Knight, 1896.

1890

1892

20th century

Skeletal reconstruction of T. rex from the original description. Tyrannosaurus skeleton.jpg
Skeletal reconstruction of T. rex from the original description.

1900s

1900

1902

1905

1910s

Skeleton of Gorgosaurus libratus. Gorgosaurus skeleton AMNH 5428.jpg
Skeleton of Gorgosaurus libratus .

1914

1917

1920s

Type specimen of Gorgosaurus sternbergi, now recognized as a juvenile Gorgosaurus libratus. Sharp naturalhistory1920 deinodon.jpg
Type specimen of Gorgosaurus sternbergi, now recognized as a juvenile Gorgosaurus libratus .

1922

Foot of Alectrosaurus olseni. Alectrosaurm olseni.jpg
Foot of Alectrosaurus olseni .

1923

1928

1930s

1930

1932

1933

1940s

Holotype skull of "Gorgosaurus" (now Nanotyrannus) lancensis. CMNH Nanotyrannus Skull.jpg
Holotype skull of "Gorgosaurus" (now Nanotyrannus ) lancensis.

1946

1950s

Holotype skull of Tarbosaurus bataar PIN 551-1, Museum of Paleontology, Moscow. Tarbosaurus holotype skull.jpg
Holotype skull of Tarbosaurus bataar PIN 551-1, Museum of Paleontology, Moscow.

1955

1956

1958

1960s

1964

1970s

Artist's restoration of Daspletosaurus torosus. Daspletosaurus torDB.jpg
Artist's restoration of Daspletosaurus torosus .

1970

1974

Skeletal mount of Alioramus remotus. Texas Alioramus.jpg
Skeletal mount of Alioramus remotus .

1975

1976

1977

1978

1979

1980s

A juvenile Tarbosaurus. Tarbosaurus specimen MPC-D 100 7.jpg
A juvenile Tarbosaurus .

1980

1981

Holotype skull of Nanotyrannus lancensis. CMNH Nanotyrannus Skull.jpg
Holotype skull of Nanotyrannus lancensis .

1983

1986

1988

1990s

Tyrannosaurs had long been classified with carnosaurs like Allosaurus (pictured). In the 1990s, this consensus began to change. Allosaurus SDNHM.jpg
Tyrannosaurs had long been classified with carnosaurs like Allosaurus (pictured). In the 1990s, this consensus began to change.

1990

Paleontologists like Abler studied tyrannosaur tooth biomechanics (Tyrannosaurus teeth pictured) in the early 1990s. B-rex teeth.jpg
Paleontologists like Abler studied tyrannosaur tooth biomechanics (Tyrannosaurus teeth pictured) in the early 1990s.

1991

1992

1993

1994

Lockley and Hunt reported a possible T. rex footprint in 1994. Philmont Scout Ranch Tyrannosaurus footprint.jpg
Lockley and Hunt reported a possible T. rex footprint in 1994.

1995

The known skeletal elements of Bagaraatan ostromi. Bagaraatan outline.jpg
The known skeletal elements of Bagaraatan ostromi .

1996

1997

1998

Skeletal mount of Santanaraptor placidus. Santanaraptor.jpg
Skeletal mount of Santanaraptor placidus .

1999

21st century

2000s

Edmontosaurus annectens tail vertebrae have been preserved with partially healed T. rex bite marks. DMNS Edmontosaurus.png
Edmontosaurus annectens tail vertebrae have been preserved with partially healed T. rex bite marks.

2000

Known skeletal elements of Eotyrannus lengi. Eotyrannus remains 01.png
Known skeletal elements of Eotyrannus lengi .

2001

Diagram of T. rex forelimb anatomy. Tyrannosaur arm 104.JPG
Diagram of T. rex forelimb anatomy.

Thomas R. Holtz, Jr. published a cladistic analysis of the Tyrannosauridae. [26] Holtz defined the Tyrannosauridae in his analysis as "all descendants of the most recent common ancestor of Tyrannosaurus and Aublysodon." [10] He concluded that the Tyrannosauridae had two subfamilies, a more primitive Aublysodontinae and the tyrannosaurinae. [26] He defined the former as "Aublysodon and all taxa sharing a more recent common ancestor with it than with Tyrannosaurus." [27]

Jaws and teeth of Gorgosaurus. Drumheller 150 cropped.jpg
Jaws and teeth of Gorgosaurus .

He observed that these dinosaurs were distinguished by their unserrated premaxillary teeth. [26] The Tyrannosaurinae he defined as "Tyrannosaurus and all taxa sharing a more recent common ancestor with it than with Aublysodon." [27]

Holtz considered these definitions only tentative due to the scant remains representing most taxa in the Aublysodontinae. [28] Holtz also noted that the lack of serrations on aublyodontines' premaxillary teeth could have been caused by tooth wear in life, postmortem abrasion, or digestion. [29] Alternatively "Aublysodontine"-type teeth could be from an ontogenetic stage or sexual morph of another kind of tyrannosaur. [29] Holtz also expressed the taxonomic opinion that Nanotyrannus lancensis was a juvenile T. rex. [10] The results of his phylogenetic analysis of the Tyrannosauridae are reproduced below:

2002

Skeletal mount of Appalachiosaurus. Appalachiosaurus.jpg
Skeletal mount of Appalachiosaurus .

2003

2004

2005

Artist's restoration of Guanlong. Guanlong wucaii head.jpg
Artist's restoration of Guanlong .

2006

2009

2010s

Artist's restoration of Xiongguanlong. Xiongguanlong NT.jpg
Artist's restoration of Xiongguanlong .

2010

2011

Artist's restoration of Yutyrannus. Feathered tyrant by pilsator-d4vbemk.jpg
Artist's restoration of Yutyrannus .

2012

2013

Artist's restoration of Nanuqsaurus. Nanuqsaurus.png
Artist's restoration of Nanuqsaurus .
Artist's restoration of Moros intrepidus. Moros intrepidus reconstruction.png
Artist's restoration of Moros intrepidus .

2014

2015

2016

2017

2018

2019

2020s

2020

See also

Footnotes

  1. Mayor (2005); "Crow Fossil Collectors," page 276.
  2. 1 2 Mayor (2005); "Cheyenne Fossil Knowledge," pages 211–212.
  3. 1 2 Mayor (2005); "Smoking the Monster's Bone: An Ancient Delaware Fossil Legend," pages 68–69.
  4. Horner (2001); "History of Dinosaur Collecting in Montana," page 44.
  5. For the implications of Dryptosaurus for theropod gait, see Holtz (2004); "Introduction", page 111. For a characterization of the Crystal Palace theropods, see Bakker (2004); page 3.
  6. Brett-Surman (1999); "1897," page 713.
  7. Moore (2014); "1866," page 62.
  8. For the discovery of T. rex, see Horner (2001); "History of Dinosaur Collecting in Montana," page 48. For the erection of the Tyrannosauridae, see Holtz (2004); "Introduction", page 114.
  9. 1 2 3 4 5 6 7 8 Holtz (2004); "Introduction", page 114.
  10. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Holtz (2004); "Systematics and Evolution", page 127.
  11. 1 2 3 4 5 6 7 8 Holtz (2004); "Paleobiology", pages 134–135.
  12. 1 2 3 4 5 6 7 8 9 10 11 Holtz (2004); "Table 5.1: Tyrannosauroidea", page 114.
  13. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Holtz (2004); "Table 5.1: Tyrannosauroidea", page 112.
  14. 1 2 Holtz (2004); "Introduction", page 111.
  15. Tanke (2010); "Background and Collection History," page 542.
  16. 1 2 3 4 5 6 7 8 9 10 11 12 13 Holtz (2004); "Table 5.1: Tyrannosauroidea", page 113.
  17. "Barnum Brown". Strange Science. 2015-06-14. Retrieved 2017-12-12.
  18. 1 2 3 4 5 6 7 8 9 10 11 12 13 Holtz (2004); "Paleobiology", page 134.
  19. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Holtz (2004); "Paleobiology", page 135.
  20. Chicago Field Museum - All About Sue
  21. Holtz (2004); "Paleobiology", pages 135–136.
  22. Holtz (2004); "Systematics and Evolution", page 133.
  23. Holtz (2004); "Systematics and Evolution", page 128.
  24. 1 2 Carpenter and Smith (2001); "Abstract," page 90.
  25. Carpenter and Smith (2001); "Introduction," page 91.
  26. 1 2 3 Holtz (2001); "Abstract," page 64.
  27. 1 2 Holtz (2001); "Results," page 66.
  28. Holtz (2001); "Results," page 66-67.
  29. 1 2 Holtz (2001); "Results," page. 67.
  30. 1 2 Abler (2001); "Abstract," page 84.
  31. Abler (2001); "Kerf-and-Drill Model," page 86.
  32. Abler (2001); "Kerf-and-Drill Model," pages 86–88.
  33. Abler (2001); "Introduction," page 84.
  34. Jacobsen (2001); "Abstract," page 58.
  35. Jacobsen (2001); "Introduction," page 59.
  36. Jacobsen (2001); "Discussion," page 61.
  37. Jacobsen (2001); "Discussion," page 60.
  38. Rauhut (2003); "Abstract," page 903.
  39. Xu et al. (2004); "Abstract," page 680.
  40. Carr, Williamson, and Schwimmer (2005); "Abstract," page 119.
  41. Carpenter, Miles, and Cloward (2005); "Abstract," page 23.
  42. Xu et al. (2006); "Abstract," page 715.
  43. Sereno et al. (2009); "Abstract," page 418.
  44. Ji, Ji, and Zhang (2009); "Abstract," page 1369.
  45. Carr and Williamson (2010); "Abstract," page 1.
  46. Averianov, Krasnolutskii, and Ivantsov (2010); "Abstract," page 42.
  47. Li et al. (2010); "Abstract," page 183.
  48. Carr et al. (2011); "Abstract," page 241.
  49. Hone et al. (2011); "Abstract," page 495.
  50. Xu et al. (2012); "Abstract," page 92.
  51. Brusatte and Benson (2013); "Abstract," page 47.
  52. Loewen et al. (2013); "Abstract," page 1.
  53. Fiorillo and Tykoski (2014); "Abstract," page 1.
  54. Lü et al. (2014); "Abstract," page 1.
  55. Hill (2015); in passim.
  56. Brusatte et al. (2016); in passim.
  57. Carr, Thomas D.; Varricchio, David J.; Sedlmayr, Jayc C.; Roberts, Eric M.; Moore, Jason R. (2017). "A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system". Scientific Reports. 7: 44942. Bibcode:2017NatSR...744942C. doi:10.1038/srep44942. PMC   5372470 . PMID   28358353.
  58. McDonald, A.T.; Wolfe, D.G.; Dooley Jr, A.C. (2018). "A new tyrannosaurid (Dinosauria: Theropoda) from the Upper Cretaceous Menefee Formation of New Mexico". PeerJ. 6: 6:e5749. doi:10.7717/peerj.5749. PMC   6183510 . PMID   30324024.
  59. Zanno, L.E.; Tucker, R.T.; Canoville, A.; Avrahami, H.M.; Gates, T.A.; Makovicky, P.J. (2019). "Diminutive fleet-footed tyrannosauroid narrows the 70-million-year gap in the North American fossil record". Communications Biology. 2 (64): 64. doi:10.1038/s42003-019-0308-7. PMC   6385174 . PMID   30820466.
  60. Martin Kundrát; Xing Xu; Martina Hančová; Andrej Gajdoš; Yu Guo; Defeng Chen (2019). "Evolutionary disparity in the endoneurocranial configuration between small and gigantic tyrannosauroids". Historical Biology: An International Journal of Paleobiology. 32 (5): 620–634. doi:10.1080/08912963.2018.1518442. S2CID   91373963.
  61. Eric Snively; Haley O’Brien; Donald M. Henderson; Heinrich Mallison; Lara A. Surring; Michael E. Burns; Thomas R. Holtz Jr; Anthony P. Russell; Lawrence M. Witmer; Philip J. Currie; Scott A. Hartman; John R. Cotton (2019). "Lower rotational inertia and larger leg muscles indicate more rapid turns in tyrannosaurids than in other large theropods". PeerJ. 7: e6432. doi:10.7717/peerj.6432. PMC   6387760 . PMID   30809441.
  62. Tomoya Hanai; Takanobu Tsuihiji (2019). "Description of tooth ontogeny and replacement patterns in a juvenile Tarbosaurus bataar (Dinosauria: Theropoda) using CT‐scan data". The Anatomical Record. 302 (7): 1210–1225. doi: 10.1002/ar.24014 . PMID   30378771. S2CID   53109996.
  63. Ingmar Werneburg; Borja Esteve-Altava; Joana Bruno; Marta Torres Ladeira; Rui Diogo (2019). "Unique skull network complexity of Tyrannosaurus rex among land vertebrates". Scientific Reports. 9 (1): Article number 1520. Bibcode:2019NatSR...9.1520W. doi:10.1038/s41598-018-37976-8. PMC   6365547 . PMID   30728455.
  64. Joseph E. Peterson; Karsen N. Daus (2019). "Feeding traces attributable to juvenile Tyrannosaurus rex offer insight into ontogenetic dietary trends". PeerJ. 7: e6573. doi:10.7717/peerj.6573. PMC   6404657 . PMID   30863686.
  65. W. Scott Persons IV; Philip J. Currie; Gregory M. Erickson (2019). "An older and exceptionally large adult specimen of Tyrannosaurus rex". The Anatomical Record. 303 (4): 656–672. doi: 10.1002/ar.24118 . PMID   30897281.
  66. "Tiny "Coyote of the Cretaceous" Fills a Gap in the Tyrannosaur Tree". PBS.
  67. Voris, Jared T.; Zelenitsky, Darla K.; Therrien, François; Currie, Philip J. (2019-11-28). "Reassessment of a juvenile Daspletosaurus from the Late Cretaceous of Alberta, Canada with implications for the identification of immature tyrannosaurids". Scientific Reports. 9 (1): 17801. Bibcode:2019NatSR...917801V. doi:10.1038/s41598-019-53591-7. ISSN   2045-2322. PMC   6882908 . PMID   31780682.
  68. Wu Xiao-chun; Shi Jian-Ru; Dong Li-Yang; Thomas D. Carr; Yi Jian; Xu Shi-Chao (2019). "A new tyrannosauroid from the Upper Cretaceous of Shanxi, China". Cretaceous Research. 108: Article 104357. doi:10.1016/j.cretres.2019.104357. S2CID   214354354.
  69. Voris, Jared T.; Therrien, Francois; Zelenitzky, Darla K.; Brown, Caleb M. (2020). "A new tyrannosaurine (Theropoda:Tyrannosauridae) from the Campanian Foremost Formation of Alberta, Canada, provides insight into the evolution and biogeography of tyrannosaurids". Cretaceous Research. 110: 104388. doi:10.1016/j.cretres.2020.104388. S2CID   213838772.

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Bistahieversor, also known as the "Bisti Beast", is a genus of basal eutyrannosaurian theropod dinosaur. The genus contains only a single known species, B. sealeyi, described in 2010, from the Late Cretaceous of New Mexico. The holotype and a juvenile were found in the Hunter Wash Member of the Kirtland Formation, while other specimens came from the underlying Fossil Forest member of the Fruitland Formation. This dates Bistahieversor approximately 75.5 to 74.5 million years ago during the Campanian age, found in sediments spanning a million years.

<i>Lythronax</i> Genus of tyrannosaurid dinosaur from the Late Cretaceous period

Lythronax is a genus of tyrannosaurid dinosaur that lived in North America around 81.9-81.5 million years ago during the Late Cretaceous period. The only known specimen was discovered in Utah in the Wahweap Formation of the Grand Staircase–Escalante National Monument in 2009, and it consists of a partial skull and skeleton. In 2013, it became the basis of the new genus and species Lythronax argestes; the generic name Lythronax means "gore king", and the specific name argestes originates from the Greek poet Homer's name for the wind from the southwest, in reference to the specimen's geographic provenance in North America.

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

Timurlengia is an extinct genus of tyrannosauroid theropod dinosaur found in Uzbekistan, in the Bissekty Formation in the Kyzylkum Desert, hailing from the Turonian age of the early Late Cretaceous. The type species is Timurlengia euotica.

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