Editing Dinosaur (section)

==="Dinosaur renaissance" and beyond===
{{Main|Dinosaur renaissance}}
[[World War II]] caused a pause in palaeontological research; after the war, research attention was also diverted increasingly to fossil mammals rather than dinosaurs, which were seen as sluggish and cold-blooded.<ref name="taylor2010">{{cite journal |last1=Taylor |first1=M.P. |title=Sauropod dinosaur research: a historical review |journal=Geological Society, London, Special Publications |year=2010 |volume=343 |issue=1 |pages=361–386 |doi=10.1144/SP343.22|bibcode=2010GSLSP.343..361T |s2cid=910635 }}</ref><ref name="Naish">{{cite book |last=Naish |first=D. |year=2009 |title=The Great Dinosaur Discoveries |pages=89–93 |publisher=A & C Black Publishers Ltd. |location=London, UK |isbn=978-1-4081-1906-8}}</ref> At the end of the 1960s, however, the field of dinosaur research experienced a surge in activity that remains ongoing.<ref name="arbour2018">{{cite journal |last1=Arbour |first1=V. |year=2018 |title=Results roll in from the dinosaur renaissance |journal=Science |volume=360 |issue=6389 |page=611 |doi=10.1126/science.aat0451|bibcode=2018Sci...360..611A |s2cid=46887409 }}</ref> Several seminal studies led to this activity. First, [[John Ostrom]] discovered the bird-like [[dromaeosauridae|dromaeosaurid]] theropod ''[[Deinonychus]]'' and described it in 1969. Its anatomy indicated that it was an active predator that was likely warm-blooded, in marked contrast to the then-prevailing image of dinosaurs.<ref name="taylor2010"/> Concurrently, [[Robert T. Bakker]] published a series of studies that likewise argued for active lifestyles in dinosaurs based on anatomical and ecological evidence (see {{section link||Physiology}}),<ref name="bakker1968"/><ref name="bakker1972"/> which were subsequently summarized in his 1986 book ''[[The Dinosaur Heresies]]''.<ref name=bakker86>{{harvnb|Bakker|1986}}</ref>

[[File:Dr. Bob Bakker with Dino.jpg|thumb|left|Paleontologist [[Robert T. Bakker]] with a mounted skeleton of a [[Tyrannosauridae|tyrannosaurid]] (''[[Gorgosaurus|Gorgosaurus libratus]]'')]]
New revelations were supported by an increase in dinosaur discoveries. Major new dinosaur discoveries have been made by paleontologists working in previously unexplored regions, including India, South America, Madagascar, Antarctica, and most significantly China. Across theropods, sauropodomorphs, and ornithischians, the number of named genera began to increase exponentially in the 1990s.<ref name="Genera900"/> In 2008 over 30 new species of dinosaurs were named each year.<ref name="benton2008"/> At least sauropodomorphs experienced a further increase in the number of named species in the 2010s, with an average of 9.3 new species having been named each year between 2009 and 2020. As a consequence, more sauropodomorphs were named between 1990 and 2020 than in all previous years combined.<ref name="cashmore2020">{{cite journal |last1=Cashmore |first1=D.D. |last2=Mannion |first2=P.D. |last3=Upchurch |first3=P. |last4=Butler |first4=R.J. |year=2020 |title=Ten more years of discovery: revisiting the quality of the sauropodomorph dinosaur fossil record |journal=Palaeontology |volume=63 |issue=6 |pages=951–978 |doi=10.1111/pala.12496|bibcode=2020Palgy..63..951C |s2cid=219090716 |doi-access=free }}</ref> These new localities also led to improvements in overall specimen quality, with new species being increasingly named not on scrappy fossils but on more complete skeletons, sometimes from multiple individuals. Better specimens also led to new species being invalidated less frequently.<ref name="benton2008">{{cite journal |last1=Benton |first1=M.J. |year=2008 |title=Fossil quality and naming dinosaurs |journal=Biology Letters |volume=4 |issue=6 |pages=729–732 |doi=10.1098/rsbl.2008.0402|pmid=18796391 |pmc=2614166 }}</ref> Asian localities have produced the most complete theropod specimens,<ref name="cashmore2019">{{cite journal |last1=Cashmore |first1=D.D. |last2=Butler |first2=R.J. |year=2019 |title=Skeletal completeness of the non-avian theropod dinosaur fossil record |journal=Palaeontology |volume=62 |issue=6 |pages=951–981 |doi=10.1111/pala.12436|s2cid=197571209 |doi-access=free |bibcode=2019Palgy..62..951C }}</ref> while North American localities have produced the most complete sauropodomorph specimens.<ref name="cashmore2020"/>

Prior to the dinosaur renaissance, dinosaurs were mostly classified using the traditional rank-based system of [[Linnaean taxonomy]]. The renaissance was also accompanied by the increasingly widespread application of [[cladistics]], a more objective method of classification based on ancestry and shared traits, which has proved tremendously useful in the study of dinosaur systematics and evolution. Cladistic analysis, among other techniques, helps to compensate for an often incomplete and fragmentary fossil record.<ref name="holtz1997">{{cite book |last1=Holtz |first1=T.R. Jr. |last2=Brett-Surman |first2=M.K. |year=1997 |chapter=The Taxonomy and Systematics of Dinosaurs |title=The Complete Dinosaur |publisher=Indiana University Press |location=Bloomington |pages=209–223 |isbn=978-0-253-33349-0 |chapter-url=https://books.google.com/books?id=Hk5ecvEv0GcC&pg=PA209}}</ref><ref name="NYT-20161208">{{cite news |last=St. Fleur |first=Nicholas |title=That Thing With Feathers Trapped in Amber? It Was a Dinosaur Tail |url=https://www.nytimes.com/2016/12/08/science/dinosaur-feathers-amber.html |url-status=live |url-access=registration |date=December 8, 2016 |department=Trilobites |work=The New York Times |location=New York |issn=0362-4331 |archive-url=https://web.archive.org/web/20170831181949/https://www.nytimes.com/2016/12/08/science/dinosaur-feathers-amber.html |archive-date=August 31, 2017 |access-date=December 8, 2016}}</ref> Reference books summarizing the state of dinosaur research, such as [[David B. Weishampel]] and colleagues' ''[[The Dinosauria]]'', made knowledge more accessible<ref name="lockley2000">{{cite journal |last1=Lockley |first1=M.G. |last2=Wright |first2=J.L. |year=2000 |title=Reading About Dinosaurs – An Annotated Bibliography of Books |journal=Journal of Geoscience Education |volume=48 |issue=2 |pages=167–178 |doi=10.5408/1089-9995-48.2.167|bibcode=2000JGeEd..48..167L |s2cid=151426669 }}</ref> and spurred further interest in dinosaur research. The release of the first and second editions of ''The Dinosauria'' in 1990 and 2004, and of a review paper by [[Paul Sereno]] in 1998, were accompanied by increases in the number of published [[phylogenetic tree]]s for dinosaurs.<ref name="lloyd2008">{{cite journal |last1=Lloyd |first1=G.T. |last2=Davis |first2=K.E. |last3=Pisani |first3=D. |last4=Tarver |first4=J.E. |last5=Ruta |first5=R. |last6=Sakamoto |first6=M. |last7=Hone |first7=D.W.E. |last8=Jennings |first8=R. |last9=Benton |first9=M.J. |year=2008 |title=Dinosaurs and the Cretaceous Terrestrial Revolution |journal=Proceedings of the Royal Society B |volume=275 |issue=1650 |pages=2483–2490 |doi=10.1098/rspb.2008.0715|pmid=18647715 |pmc=2603200 }}</ref>