Timeline of troodontid research

Last updated
Artistic restoration of Byronosaurus with secretary bird-like plumage Byronosaurus.jpg
Artistic restoration of Byronosaurus with secretary bird-like plumage

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. [1] 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. [2]

Contents

Many milestones of troodontid research occurred between the description of Troodon and the resolution of their confusion with pachycephalosaurs. The family itself was named by Charles Whitney Gilmore in 1924. [2] That same year Henry Fairfield Osborn named the genus Saurornithoides . [3] In the 1960s and 1970s researchers like Russell and Hopson observed that troodontids had very large brains for their body size. Both attributed this enlargement of the brain to a need for processing the animal's especially sharp senses. [4] Also in the 1970s, Barsbold described the new species Saurornithoides (now Zanabazar ) junior [3] and named the family Saurornithoidae, but as noted this was just a junior synonym of the Troodontidae in the first place. [2]

In the 1980s Gauthier classed them with the dromaeosaurids in the Deinonychosauria. [2] That same decade Jack Horner reported the discovery of Troodon nests in Montana. [5] Interest in the life history of Troodon continued in the 1990s with a study of its growth rates based on histological sections of fossils taken from a bonebed in Montana [4] and the apparent pairing of eggs in Troodon nests. [5] This decade also saw the first potential report of European troodontid remains, although this claim has been controversial. [4] A single mysterious tooth from the Late Jurassic Morrison Formation of the United States was described as the oldest known troodontid remains, although this has also been controversial. [2] In the 2000s, several new kinds of troodontid were named, like Byronosaurus and Sinovenator . [3]

19th century

The Troodon formosus holotype tooth Troodon formosus.jpg
The Troodon formosus holotype tooth

1850s

1856

1870s

Paronychodon teeth Paronychodon.png
Paronychodon teeth

1876

1877

20th century

Holotype skull of Saurornithoides Saurornithoides.jpg
Holotype skull of Saurornithoides

1900s

1901

1910s

1913

1920s

1924

1930s

Partial Stenonychosaurus inequalis skull, now attributed to Latenivenatrix Latenivenatrix skull.jpg
Partial Stenonychosaurus inequalis skull, now attributed to Latenivenatrix

1932

1940s

1945

1960s

1964

1969

1970s

Artist's restoration of Saurornithoides (now Zanabazar) junior Zanabazar.jpg
Artist's restoration of Saurornithoides (now Zanabazar) junior

1974

1975

1977

1980s

The feet of Borogovia Borogovia feet.jpg
The feet of Borogovia

1982

1985

1986

Troodontids were formally distinguished from pachycephalosaurs in the 1980s. Pachycephalosaurus Clean.png
Troodontids were formally distinguished from pachycephalosaurs in the 1980s.

1987

1990s

Two Paronychodon teeth Paronychodon.png
Two Paronychodon teeth

1990

Limb bones of Tochisaurus Tochisaurus.jpg
Limb bones of Tochisaurus

1991

Artistic restoration of Sinornithoides youngi Sinornithoides-youngi jconway.png
Artistic restoration of Sinornithoides youngi

1993

1994

1995

Troodon eggs continued to attract scholarly attention in the 1990s. Troodon clutch.jpg
Troodon eggs continued to attract scholarly attention in the 1990s.

1996

1997

1998

In the 1990s, Thomas Holtz argued that troodontids were close relatives of the ornithomimosaurs (example pictured), although this is no longer widely accepted. Beishanlong grandis.jpg
In the 1990s, Thomas Holtz argued that troodontids were close relatives of the ornithomimosaurs (example pictured), although this is no longer widely accepted.

1999

21st century

2000s

2000

Sinovenator fossils Fossil Japan.jpg
Sinovenator fossils
Illustration of Sinovenator with a human to scale SinovenatorSIZE.png
Illustration of Sinovenator with a human to scale

2001

2002

Artist's restoration of Mei Meilong mmartyniuk wiki.png
Artist's restoration of Mei

2004

2005

Artist's restoration of Anchiornis Anchiornis martyniuk.png
Artist's restoration of Anchiornis

2007

2009

2010s

Artist's restoration of Xixiasaurus Xixiasaurus.jpg
Artist's restoration of Xixiasaurus

2010

2011

Artist's restoration of Gobivenator Gobivenator Restoration.jpg
Artist's restoration of Gobivenator

2012

2014

2017

2019

2020

See also

Footnotes

  1. Horner (2001); "History of Dinosaur Collecting in Montana", page 44.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Makovicky and Norell (2004); "Introduction", page 184.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Makovicky and Norell (2004); "Table 9.1: Troodontidae", page 185.
  4. 1 2 3 4 5 6 7 8 9 10 11 12 Makovicky and Norell (2004); "Paleobiology", page 194.
  5. 1 2 3 4 5 6 Makovicky and Norell (2004); "Paleobiology", page 195.
  6. 1 2 3 4 5 6 7 8 Makovicky and Norell (2004); "Table 9.1: Troodontidae", page 186.
  7. Cope (1877).
  8. Nopcsa (1901).
  9. Kessler, Grigorescu, and Csiki (2005).
  10. Sternberg (1945).
  11. Holtz (2011); "Winter Appendix 2010".
  12. 1 2 3 Makovicky and Norell (2004); "Systematics and Evolution", page 193.
  13. 1 2 3 Makovicky and Norell (2004); "Biogeography", page 194.
  14. Makovicky and Norell (2004); "Definition and Diagnosis", page 184.
  15. 1 2 Makovicky and Norell (2004); "Systematics and Evolution", pages 193–194.
  16. Padian, Ji, and Ji (2001); "Abstract," page 117.
  17. Padian, Ji, and Ji (2001); "Conclusions," pages 131–132.
  18. Padian, Ji, and Ji (2001); "Conclusions," page 132.
  19. 1 2 Norell and Makovicky (2004); "Systematics and Evolution", page 207.
  20. Makovicky and Norell (2004); "Systematics and Evolution", page 194.
  21. Xu and Norell (2004); "Abstract," page 838.
  22. Xu and Wang (2004); "Abstract," page 22.
  23. Ji et al. (2005); "Abstract," page 197.
  24. Averianov and Sues (2007); "Abstract," page 87.
  25. Xu et al. (2009); "Abstract," page 430.
  26. Norell et al. (2009); "Abstract," page 63.
  27. Senter et al. (2010); "Abstract," page 1.
  28. Lü et al. (2010); "Abstract," page 381.
  29. Xu et al. (2011); "Abstract," page 1.
  30. Zanno et al. (2011); "Abstract," page 1.
  31. Xu et al. (2012); "Abstract," page 140.
  32. Tsuihiji et al. (2014); "Abstract," page 131.
  33. Varricchio, David J.; Kundrát, Martin; Hogan, Jason (2018). "An Intermediate Incubation Period and Primitive Brooding in a Theropod Dinosaur". Scientific Reports. 8 (1): 12454. Bibcode:2018NatSR...812454V. doi:10.1038/s41598-018-30085-6. PMC   6102251 . PMID   30127534.
  34. Hartman, Scott; Mortimer, Mickey; Wahl, William R.; Lomax, Dean R.; Lippincott, Jessica; Lovelace, David M. (2019). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247. doi: 10.7717/peerj.7247 . PMC   6626525 . PMID   31333906.

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References