Editing Velociraptor (section)

===Predatory behavior===
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|image1 = Fighting dinosaurs (1).jpg
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|footer = The "Fighting Dinosaurs" specimen of ''V. mongoliensis'' and ''Protoceratops andrewsi'' and restoration of same
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The "[[Fighting Dinosaurs]]" specimen, found in 1971, preserves a ''Velociraptor mongoliensis'' and ''[[Protoceratops|Protoceratops andrewsi]]'' in combat and provides direct evidence of predatory behavior. When originally reported, it was hypothesized that the two animals drowned.<ref name=barsbold1974/> However, as the animals were preserved in ancient sand dune deposits, it is now thought that the animals were buried in sand, either from a collapsing dune or in a [[Dust storm|sandstorm]]. Burial must have been extremely rapid, judging from the lifelike poses in which the animals were preserved. Parts of the ''Protoceratops'' are missing, which has been seen as evidence of [[scavenger|scavenging]] by other animals.<ref name=carpenter1998>{{cite journal|last=Carpenter |first=Kenneth |author-link=Kenneth Carpenter |year=1998 |title=Evidence of predatory behavior by theropod dinosaurs |journal=Gaia |volume=15 |pages=135–144 |url=http://www.mnhn.ul.pt/geologia/gaia/9.pdf |url-status=dead |archive-url=https://web.archive.org/web/20110719060017/http://www.mnhn.ul.pt/geologia/gaia/9.pdf |archive-date=19 July 2011 }}</ref> Comparisons between the [[sclerotic ring|scleral rings]] of ''Velociraptor'', ''Protoceratops'', and modern birds and reptiles indicates that ''Velociraptor'' may have been [[nocturnal]], while ''Protoceratops'' may have been [[cathemeral]], active throughout the day during short intervals, suggesting that the fight may have occurred at twilight or during low-light conditions.<ref>{{cite journal|author1=Schmitz, L. |author2=Motani, R. |year=2011 |title=Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology |journal=Science |volume=332 |issue=6030|pages=705–8|doi=10.1126/science.1200043 |pmid=21493820|bibcode=2011Sci...332..705S|s2cid=33253407 }}</ref>
[[File:Fighting Dinosaurs size.png|thumb|Size comparison of the Fighting Dinosaurs]]
The distinctive claw, on the second digit of dromaeosaurids, has traditionally been depicted as a slashing weapon; its assumed use being to cut and [[disembowel]] prey.<ref name=ostrom1969>{{cite book |last=Ostrom |first=John H. |author-link=John Ostrom |year=1969 |title=Osteology of ''Deinonychus antirrhopus'', an unusual theropod from the Lower Cretaceous of Montana |journal=Bulletin of the Peabody Museum of Natural History |volume=30 |pages=1–165|doi=10.2307/j.ctvqc6gzx|s2cid=210733704 }}</ref> In the "Fighting Dinosaurs" specimen, the ''Velociraptor'' lies underneath, with one of its sickle claws apparently embedded in the throat of its prey, while the beak of ''Protoceratops'' is clamped down upon the right forelimb of its attacker. This suggests ''Velociraptor'' may have used its sickle claw to pierce vital organs of the throat, such as the [[jugular vein]], [[carotid artery]], or [[vertebrate trachea|trachea]] (windpipe), rather than slashing the abdomen. The inside edge of the claw was rounded and not unusually sharp, which may have precluded any sort of cutting or slashing action, although only the bony core of the claw is preserved. The thick abdominal wall of [[skin]] and [[muscle]] of large prey species would have been difficult to slash without a specialized cutting surface.<ref name=carpenter1998/> The slashing [[hypothesis]] was tested during a 2005 [[BBC]] documentary, ''[[The Truth About Killer Dinosaurs]]''. The producers of the program created an artificial ''Velociraptor'' leg with a sickle claw and used a [[pork belly]] to simulate the dinosaur's prey. Though the sickle claw did penetrate the abdominal wall, it was unable to tear it open, indicating that the claw was not used to disembowel prey.<ref>{{cite journal |last1=Manning |first1=P. L. |last2=Payne |first2=D. |last3=Pennicott |first3=J. |last4=Barrett |first4=P. M. |last5=Ennos |first5=R. A. |year=2006 |title=Dinosaur killer claws or climbing crampons? |journal=Biology Letters |volume=2 |issue=1|pages=110–112 |doi=10.1098/rsbl.2005.0395 |pmid=17148340 |pmc=1617199}}</ref>

Remains of ''[[Deinonychus]]'', a closely related dromaeosaurid, have commonly been found in aggregations of several individuals. ''Deinonychus'' has also been found in association with the large ornithopod ''[[Tenontosaurus]]'', which has been cited as evidence of cooperative (pack) hunting.<ref name=maxwellostrom1995>{{cite journal|doi=10.1080/02724634.1995.10011256 |last1=Maxwell |first1=W. Desmond |author-link2=John Ostrom |last2=Ostrom |first2=John H. |year=1995 |title=Taphonomy and paleobiological implications of Tenontosaurus-Deinonychus associations |journal=Journal of Vertebrate Paleontology |volume=15 |issue=4 |pages=707–712 |bibcode=1995JVPal..15..707M |url=http://vertpaleo.org/publications/jvp/15-707-712.cfm |url-status=dead |archive-url=https://web.archive.org/web/20070927204328/http://www.vertpaleo.org/publications/jvp/15-707-712.cfm |archive-date=27 September 2007 }}</ref><ref name=brinkmanetal1998>{{cite journal |last1=Brinkman |first1=Daniel L. |last2=Cifelli |first2=Richard L. |last3=Czaplewski |first3=Nicholas J. |year=1998 |title=First occurrence of ''Deinonychus antirrhopus'' (Dinosauria: Theropoda) in the Antlers Formation (Lower Cretaceous: Aptian-Albian) of Oklahoma |journal=Oklahoma Geological Survey Bulletin |volume=146 |pages=1–27 |url=http://www.ogs.ou.edu/pubsscanned/BULLETINS/Bulletin146.pdf |archive-date=19 August 2018 |access-date=21 August 2010 |archive-url=https://web.archive.org/web/20180819045405/http://www.ogs.ou.edu/pubsscanned/BULLETINS/Bulletin146.pdf |url-status=live }}</ref> However, the only solid evidence for social behavior of any kind among dromaeosaurids comes from a Chinese trackway which shows six individuals of a large species moving as a group.<ref name="Lietal2007">{{cite journal |first1=Rihui |last1=Li |last2=Lockley |first2=M.G. |last3=Makovicky |first3=P.J. |last4=Matsukawa |first4=M. |last5=Norell |first5=M.A. |last6=Harris |first6=J.D. |last7=Liu |first7=M. |title=Behavioral and faunal implications of Early Cretaceous deinonychosaur trackways from China |year=2007 |pmid=17952398 |journal=Die Naturwissenschaften |volume=95 |issue=3 |pages=185–191 |doi=10.1007/s00114-007-0310-7 |bibcode=2008NW.....95..185L|s2cid=16380823 }}</ref> Although many isolated fossils of ''Velociraptor'' have been found in Mongolia, none were closely associated with other individuals.<ref name=norellmakovicky2004/> Therefore, while ''Velociraptor'' is commonly depicted as a [[pack hunter]], as in ''Jurassic Park'', there is only limited fossil evidence to support this theory for dromaeosaurids in general and none specific to ''Velociraptor'' itself. Dromeosaur footprints in China suggest that a few other raptor genera may have hunted in packs, but there have been no conclusive examples of pack behavior found.<ref>{{cite news | title=Dinosaurs behaving badly: Did velociraptors hunt in packs? | url=https://www.theguardian.com/science/blog/2011/mar/29/dinosaurs-behaviour-raptors-pack-hunters | newspaper=The Guardian | first=Brian | last=Switek | date=29 March 2011 | access-date=17 September 2020 | archive-date=25 May 2023 | archive-url=https://web.archive.org/web/20230525041612/https://www.theguardian.com/science/blog/2011/mar/29/dinosaurs-behaviour-raptors-pack-hunters | url-status=live }}</ref><ref>Long, John, and Schouten, Peter. (2008). ''Feathered Dinosaurs: The Origin of Birds''. Oxford and New York: Oxford University Press. {{ISBN|978-0-19-537266-3}}, p. 21.</ref>
[[File:Velociraptor restraining an oviraptorosaur by durbed.jpg|left|thumb|''V. mongoliensis'' restraining an [[oviraptorosaur]] with its sickle claws]]
In 2011, Denver Fowler and colleagues suggested a new method by which dromaeosaurs like ''Velociraptor'' and similar dromaeosaurs may have captured and restrained prey. This model, known as the "raptor prey restraint" (RPR) model of predation, proposes that dromaeosaurs killed their prey in a manner very similar to extant [[Accipitridae|accipitrid]] [[birds of prey]]: by leaping onto their quarry, pinning it under their body weight, and gripping it tightly with the large, sickle-shaped claws. These researchers proposed that, like accipitrids, the dromaeosaur would then begin to feed on the animal while it was still alive, and prey death would eventually result from blood loss and organ failure. This proposal is based primarily on comparisons between the morphology and proportions of the feet and legs of dromaeosaurs to several groups of extant birds of prey with known predatory behaviors. Fowler found that the feet and legs of dromaeosaurs most closely resemble those of [[eagle]]s and [[hawk]]s, especially in terms of having an enlarged second claw and a similar range of grasping motion. The short [[Tarsometatarsus|metatarsus]] and foot strength, however, would have been more similar to that of [[owl]]s. The RPR method of predation would be consistent with other aspects of ''Velociraptor''{{'}}s anatomy, such as their unusual jaw and arm morphology. The arms, which could exert a lot of force but were likely covered in long feathers, may have been used as flapping stabilizers for balance while atop a struggling prey animal, along with the stiff counterbalancing tail. The jaws, thought by Fowler and colleagues to be comparatively weak, would have been useful for row saw motion bites like the modern day [[Komodo dragon]], which also has a weak bite, to finish off its prey if the kicks were not powerful enough. These predatory adaptations working together may also have implications for the [[Origin of avian flight|origin of flapping]] in [[paravian]]s.<ref name=fowler2011>{{cite journal |last1=Fowler |first1=D.W. |last2=Freedman |first2=E.A. |last3=Scannella |first3=J.B. |last4=Kambic |first4=R.E. |year=2011 |title=The Predatory Ecology of ''Deinonychus'' and the Origin of Flapping in Birds |journal=PLOS ONE |volume=6 |issue=12|page=e28964 |doi=10.1371/journal.pone.0028964 |pmid=22194962 |bibcode=2011PLoSO...628964F |pmc=3237572|doi-access=free }}</ref>