Editing Quetzalcoatlus (section)

===Discovery and naming===
[[File:Big_Bend_Chihuahuan_Desert.jpg|thumb|left|The known fossils of ''Quetzalcoatlus'' were discovered in [[Big Bend National Park]], [[Texas]]]]
The genus ''Quetzalcoatlus'' is based on fossils discovered in rocks pertaining to the Late Cretaceous [[Javelina Formation]] in [[Big Bend National Park]], [[Texas]]. Remains of dinosaurs and other prehistoric life had been found in the area since the beginning of the 20th century. The first ''Quetzalcoatlus'' fossils were discovered in 1971 by the graduate student [[Douglas A. Lawson]] while conducting field work for his [[Master of Science|Master's degree]] project on the [[paleoecology]] of the Javelina Formation. This field work was supervised by [[Wann Langston Jr.]], an experienced [[paleontologist]] who had been doing field work in the region since 1938 and since 1963 led expeditions through his position as [[curator]] at the [[Texas Science and Natural History Museum]].{{efn|At that time known as the Texas Memorial Museum}}<ref>{{cite web |title=History of the Museum |url=https://sciencemuseum.utexas.edu/about/history |publisher=The University of Texas at Austin |access-date=September 21, 2023}}</ref> The two had first visited the park together in March 1970, with Lawson discovering the first ''Tyrannosaurus rex'' fossil from Texas. Returning in 1971, Lawson discovered a {{cvt|3|ft}} bone while investigating an [[Arroyo (watercourse)|arroyo]] on the western edge of the park, and returned to [[Austin, Texas|Austin]] with a {{cvt|1|ft}} section of it. He and Langston then identified it as a [[pterosaur]] fossil based on its hollow internal structure with thin walls. Returning in November 1971 for further excavations, they were struck by the unprecedented size of the remains compared to known pterosaurs.<ref name=brown2021>{{cite journal | title=The discovery, local distribution, and curation of the giant azhdarchid pterosaurs from Big Bend National Park | last1=Brown | first1=Matthew A. | last2=Sagebiel | first2=J. Chris | last3=Andres | first3=Brian | journal=Journal of Vertebrate Paleontology | year=2021 | volume=41 | issue=sup1 | pages=2–20 | doi=10.1080/02724634.2020.1780599| doi-access=free | bibcode=2021JVPal..41S...2B }}</ref> The initial material consisted of a giant radius and ulna, two fused wristbones known as syncarpals, and the end of the wing finger. Altogether, the material comprised a partial left wing from an individual (specimen number TMM 41450-3) later estimated at over {{cvt|10|m}} in [[wingspan]].<ref name=brown2021/><ref name="andres2021">{{cite journal |last1=Andres |first1=B. |last2=Langston |first2=W. Jr. |year=2021 |title=Morphology and taxonomy of ''Quetzalcoatlus'' Lawson 1975 (Pterodactyloidea: Azhdarchoidea) |journal=Journal of Vertebrate Paleontology |volume=41 |issue=sup1 |pages=46–202 |bibcode=2021JVPal..41S..46A |doi=10.1080/02724634.2021.1907587 |issn=0272-4634 |s2cid=245125409 |doi-access=free}}</ref> Lawson described the remains in his 1972 thesis as "[[Pteranodon]] gigas", and diagnosed it as being "nearly twice as large as any previously described species of ''Pteranodon''".<ref>{{Cite book |last=Lawson |first=Douglas Allan |author-link=Douglas A. Lawson |url=https://books.google.com/books?id=fuzmtgAACAAJ |title=Paleoecology of the Tornillo Formation, Big Bend National Park, Brewster County, Texas |date=1972 |publisher=University of Texas at Austin. |language=en}}</ref><ref name=andres2021/> As a thesis is not recognized as a published worked by the [[International Code for Zoological Nomenclature]] (ICZN), "Pteranodon gigas" is not a [[Valid name (zoology)|valid name]].<ref name=andres2021/> Further field work at the site was conducted in March 1973, when fragments were found alongside a long and delicate bone connected to an apparently larger element. This fossil was left in the ground until April 1974, when they fully excavated the larger element, a humerus. Due to the close association of discovered remains, Langston felt confident there were nothing more to be found at the site. Several later excavations of the site have indeed been unsuccessful.<ref name=brown2021/>
[[File:YB49-2_300.jpg|thumb|The name of ''Q. northropi'' refers to its similar appearance to aircraft designed by [[Jack Northrop|John Knudsen Northrop]]]]
Lawson announced his discovery in the journal ''[[Science (journal)|Science]]'' in March 1975, with a depiction of the animal's size compared to a large aircraft and a ''Pteranodon'' gracing the cover of the issue. Lawson wrote that it was "without doubt the largest flying animal presently known". He illustrated and  briefly described the remains known at the time, but did not offer a name and indicated that a more extensive description was in preparation that would diagnose the species.<ref name=brown2021/><ref name="lawson1975">{{cite journal |last1=Lawson |first1=Douglas A. |year=1975 |title=Pterosaur from the Latest Cretaceous of West Texas: Discovery of the largest flying creature |department=Reports |journal=Science |volume=187 |issue=4180 |pages=947–948 |bibcode=1975Sci...187..947L |doi=10.1126/science.187.4180.947 |pmid=17745279 |s2cid=46396417}}</ref> In May, he submitted a short response to his original paper to the journal, considering how such an enormous animal could have flown. Within the paper, he briefly established the name ''Quetzalcoatlus northropi'', but did still not provide a diagnosis or a more detailed description, which would later cause nomenclatural problems.<ref name=andres2021/><ref name="lawson1975b">{{cite journal | url=https://www.science.org/doi/abs/10.1126/science.188.4189.676.b | title=Response: Could Pterosaurs Fly? | author=Lawson, Douglas A. | journal=Science | year=1975 | volume=188 | issue=4189 | pages=676–678 | doi=10.1126/science.188.4189.676.b}}</ref> Though not specified in the original publication, Lawson's named the genus after the [[Aztecs|Aztec]] feathered serpent god [[Quetzalcoatl|Quetzalcōātl]], while the [[specific name (zoology)|specific name]] honors [[Jack Northrop|John Knudsen Northrop]], the founder of [[Northrop Corporation]], who drove the development of large tailless [[Northrop YB-49]] aircraft designs resembling ''Quetzalcoatlus''.<ref name="andres2021"/> The discovery of the giant pterosaur left a strong impression on both the scientific community and the general public, and was reported on throughout the world.<ref name=andres2021/> It was featured in [[Time Magazine]] and appeared on the cover of [[Scientific American]] in 1981 alongside an article on pterosaurs by Langston.<ref name=brown2021/> The species would become referenced by over 500 scientific publications, with ''Quetzalcoatlus northropi'' becoming the single most cited pterosaur species and ''Quetzalcoatlus'' the fourth most cited pterosaur genus after ''Pteranodon'', ''[[Rhamphorhynchus]]'', and ''[[Pterodactylus]]'', much older genera with many more species than ''Quetzalcoatlus''.<ref name=andres2021/>
[[File:Pterosaur_Texas_Science_and_Natural_History_Museum_Austin_2024.jpg|thumb|left|Skeleton reconstruction of ''Quetzalcoatlus'' at the [[Texas Science and Natural History Museum]], originally mounted by Langston in the 1980s]]
Prior to the announcement of the discovery, Langston had returned to Big Bend with a group of fossil preparators in February 1973, primarily aiming to excavate bones of the dinosaur ''[[Alamosaurus]]''. One of the preparators, a young man named Bill Amaral who went on to be a respected field worker, had been skipping his lunches to conduct additional explorations of the area.<ref name=brown2021/> He came across some additional fragments of pterosaur bone on a different portion of the ridge, around 50 kilometers away from the original site.<ref name=brown2021/><ref name=andres2021/> Two more new sites quickly followed nearby, producing many fragments which the crew figured could be fit back together, in addition to a complete carpal and intact wing bone. Langston noted in his field notes that none of these bones suggested animals as large as Lawson's original specimen. Further remains came from Amaral's first site in April 1974, after Lawson's site had been exhausted; a long neck vertebra and a pair of jawbones appeared. Associated structures were initially hoped to represent filamentous [[pycnofibres]], but were later confirmed to be conifer needles. Near the end of the 1974 season, Langston stumbled over a much more complete pterosaur skeleton; it consisted of a wing, multiple vertebrae, a femur and multiple other long bones. They lacked time to fully excavate it, leaving it in the ground until the next field season. This area, where many smaller specimens began to emerge, came to be known as Pterodactyl Ridge.<ref name=brown2021/> Two of the smaller individuals were reported in the first 1975 paper by Lawson, presumed to belong to the same species, though Langston would begin to question the idea they belonged to ''Q. northropi'' by the early 1980s.<ref name=andres2021/><ref name="lawson1975"/> Excavations continued in 1976, and eight new specimens emerged in 1977; in 1979, despite complications due to losing the field notes form 1977, Langston discovered another new site that would produce an additional ten specimens. Most importantly, a humerus of the smaller animal was finally found, which Langston considered of great importance to understanding ''Quetzalcoatlus''. Several further new localities followed in 1980, but 1981 proved less successful and Langston began to suspect the ridge may have been mostly depleted of pterosaur fossils. There was similarly little success in 1982, and visits during 1983 and 1985 proved to provide the last substantive discoveries of ''Quetzalcoatlus'' fossils. Langston returned in 1989, 1991, 1992, and 1996, but only found isolated bones and fragments. Eventually a handful of additional specimens were discovered by former student Thomas Lehman. A visit to Lawson's initial site during 1991 showed that all traces of excavation had by now eroded away. Langston would visit Big Bend for the last time in 1999, having concluded the pterosaur expeditions to focus on the excavation of two skulls of ''[[Deinosuchus]]'', another famous fossil of the area.<ref name=brown2021/>