Timeline of ichthyosaur research explained

This timeline of ichthyosaur research is a chronological listing of events in the history of paleontology focused on the ichthyosauromorphs, a group of secondarily aquatic marine reptiles whose later members superficially resembled dolphins, sharks, or swordfish. Scientists have documented ichthyosaur fossils at least as far back as the late 17th century. At that time, a scholar named Edward Lhuyd published a book on British fossils that misattributed some ichthyosaur vertebrae to actual fishes; their true nature was not recognized until the 19th century. In 1811, a boy named Joseph Anning discovered the first ichthyosaur fossils that would come to be scientifically recognized as such. His sister Mary would later find the rest of its skeleton and would go on to become a respected fossil collector and paleontologist in her own right.

Early researchers recognized ichthyosaurs as marine reptiles, but major aspects of their anatomy and behavior needed to be resolved. They were frequently portrayed as leaving the water to bask on rocks and with straight tails. Although a bend in ichthyosaurs' tail vertebrae was seen from the earliest specimens, scholars assumed the bend reflected damage incurred to the animal's carcass after death. This bend was so common, however, that scholars eventually realized that it was natural and supported a shark-like tail fin. Scientists came to realize that ichthyosaurs were too adapted to leave the water even to lay eggs. Evidence for live birth in ichthyosaurs dates back as far as 1846, when Chaning Pierce reported an apparent fossil Ichthyosaurus embryo to Sir Richard Owen.

Ichthyosaur discoveries continued to be made into the 20th century. In 1928, Simeon Muller discovered the remains of 40 gigantic ichthyosaurs in Nevada. However, these remains would not be excavated until Charles Camp and Samuel Welles of Berkeley led an expedition for the purpose in the mid 1950s. These fossils would take more than a decade to excavate, and the results of Camp's examination of the bones would not be published until a year after his 1975 death. These giant ichthyosaurs were named Shonisaurus popularis and their final resting place is now known as Berlin-Ichthyosaur state park.

Other notable late 20th century advances in ichthyosaur research include the recognition of a new genus of ichthyosaur called Eurhinosaurus longirostris that had been misclassified as a species of Ichthyosaurus since 1854. In 1986 Christopher McGowan would describe another, similar animal serendipitously discovered in England as Excalibosaurus, after King Arthur's mythical sword. The late 1990s and early 21st century would see scholarly debate regarding the cause of the ichthyosaurs' extinction, especially regarding the potential role played by competition with the mosasaurs which had evolved around the time.

17th century

1699

19th century

1810s

1811

1812

1814

1818

1819

1820s

1822

1823

1824

1830s

1830

1834

1840s

1840

1843

1844

1846

1850s

1851

1852

1853

1854

1858

1860s

1860

1866

1867

1868

1870s

1871

1874

1876

1879

1880s

1880

1881

1886

1887

1888

1889

1890s

1895

20th century

1900s

1902

1903

1904

1906

1908

1909

1910s

1910

1916

1920s

1922

1925

1926

1927

1928

1929

1930s

1931

1934

1939

1940s

1946

1948

1950s

1951

1954

1956

1957

1960s

1963

1965

1968

1970s

1972

1973

1974

1975

1976

1978

1979

1980s

1980

1983

1984

1985

1986

1987

1988

1989

1990s

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

March 6th

September

21st century

2000s

2000

May

2001

2002

2003

2004

2006

2007

2008

2010s

2010

2011

2012

2013

2014

2015

2016

2017

2018

2019

2020

See also

References

Notes and References

  1. Beiträge zur Kenntnis der Ichthyosaurier im deutschen Muschelkalk. Friedrich. von Huene. Friedrich von Huene. Tübingen. Palaeontographica. 62. 1–68. 1916. de.
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  4. Cheng Ji . Da-Yong Jiang . Ryosuke Motani . Olivier Rieppel . Wei-Cheng Hao . Zuo-Yu Sun . amp . 2015 . Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China . Journal of Vertebrate Paleontology . 36 . 1 . e1025956 . 10.1080/02724634.2015.1025956 . 85621052 .
  5. Jeremy E. Martin . Peggy Vincent . Guillaume Suan . Tom Sharpe . Peter Hodges . Matt Williams . Cindy Howells . Valentin Fischer . amp . 2015 . A mysterious giant ichthyosaur from the lowermost Jurassic of Wales . Acta Palaeontologica Polonica . 60 . 4 . 837–842 . 10.4202/app.00062.2014 . free .
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  41. Katherine L. Anderson . Patrick S. Druckenmiller . Gregory M. Erickson . Erin E. Maxwell . 2019 . Skeletal microstructure of Stenopterygius quadriscissus (Reptilia, Ichthyosauria) from the Posidonienschiefer (Posidonia Shale, Lower Jurassic) of Germany . Palaeontology . 62 . 3 . 433–449 . 10.1111/pala.12408 . 2019Palgy..62..433A . free .
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  44. Nikolay G. Zverkov . Vladimir M. Efimov . 2019. Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm . Journal of Systematic Palaeontology . 17. 14. 963–993. 10.1080/14772019.2018.1515793 . 2019JSPal..17.1183Z . 91912834 .
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  47. Lisandro Campos . Marta S. Fernández . Yanina Herrera . 2020 . A new ichthyosaur from the Late Jurassic of north-west Patagonia (Argentina) and its significance for the evolution of the narial complex of the ophthalmosaurids . Zoological Journal of the Linnean Society . 188 . 1 . 180–201 . 10.1093/zoolinnean/zlz095 . free .
  48. Jian-dong Huang . Ryosuke Motani . Da-yong Jiang. Andrea Tintori. Olivier Rieppel . Min Zhou. Xin-Xin Ren. Rong Zhang . 2019 . The new ichthyosauriform Chaohusaurus brevifemoralis (Reptilia, Ichthyosauromorpha) from Majiashan, Chaohu, Anhui Province, China . PeerJ . 7 . e7561 . 10.7717/peerj.7561 . 31565558 . 6741286 . free .
  49. Jair Israel Barrientos Lara . Jesús Alvarado Ortega . Marta S.Fernández . 2020 . Acuetzpalin carranzai gen et sp. nov. A new ophthalmosauridae (Ichthyosauria) from the Upper Jurassic of Durango, North Mexico . Journal of South American Earth Sciences . 98 . Article 102456 . 10.1016/j.jsames.2019.102456 . 2020JSAES..9802456B . 213102661 .