Editing Compsognathus (section)

==Description==
[[File:Compysizes1.png|thumb|left|Size comparison of the French (orange) and German (green) specimens, with a human]]
For decades, ''Compsognathus'' was known as the [[dinosaur size|smallest known non-avian dinosaur]],<ref name=ostrom78/> although some dinosaurs discovered later, such as ''[[Mahakala omnogovae|Mahakala]]'' and ''[[Microraptor]]'', were even smaller.<ref name="campione2014">{{Cite journal| volume = 5| issue = 9| pages = 913–923| last1 = Campione| first1 = N.E.| last2 = Evans| first2 = D.C.| last3 = Brown| first3 = C.M.| last4 = Carrano| first4 = M.T.| title = Body mass estimation in non-avian bipeds using a theoretical conversion to quadruped stylopodial proportions| journal = Methods in Ecology and Evolution| date = 2014 |doi=10.1111/2041-210X.12226| bibcode = 2014MEcEv...5..913C| s2cid = 84317234| doi-access = free}}</ref><ref name="agnolin2019">{{Cite journal| doi = 10.3389/feart.2018.00252| issn = 2296-6463| volume = 6| last1 = Agnolin| first1 = Federico L.| last2 = Motta| first2 = Matias J.| last3 = Brissón Egli| first3 = Federico| last4 = Lo Coco| first4 = Gastón| last5 = Novas| first5 = Fernando E.| title = Paravian Phylogeny and the Dinosaur-Bird Transition: An Overview| journal = Frontiers in Earth Science| date = 2019| page = 252| bibcode = 2018FrEaS...6..252A| doi-access = free| hdl = 11336/130197| hdl-access = free}}</ref> The German specimen was estimated to be {{convert|70–75|cm|abbr=on}}<ref name=ostrom78/> and {{convert|89|cm|abbr=on}}<ref name=GSP88/> in length by separate authors, while the larger French specimen was estimated at {{convert|1.25|m|abbr=on}}<ref name=GSP88/> and {{convert|1.4|m|abbr=on}}<ref name=peyer06/> in length. The height at the hip has been estimated at {{convert|20|cm|abbr=on}} for the German specimen and at {{convert|29|cm|abbr=on}} for the French specimen.<ref name=GSP88/> The German specimen was estimated to have weighed {{convert|0.32|kg|abbr=on}}<ref name=TH07>{{cite journal |last=Therrien |first=F. |author2=Henderson, D.M. |year=2007 |title=My theropod is bigger than yours...or not: estimating body size from skull length in theropods |journal=Journal of Vertebrate Paleontology |volume=27 |issue=1 |pages=108–115 |doi=10.1671/0272-4634(2007)27[108:MTIBTY]2.0.CO;2|s2cid=86025320 }}</ref> and {{convert|0.58|kg|abbr=on}},<ref name=GSP88/> and the French specimen {{convert|2.5|kg|abbr=on}}<ref name=GSP88/> and {{convert|3.5|kg|abbr=on}}.<ref name="seebacher2001">{{cite journal | doi = 10.1671/0272-4634(2001)021[0051:ANMTCA]2.0.CO;2 | last1 = Seebacher | first1 = F. | year = 2001 | title = A new method to calculate allometric length-mass relationships of dinosaurs | url = http://dinoweb.ucoz.ru/_fr/4/A_new_method_to.pdf | journal = Journal of Vertebrate Paleontology | volume = 21 | issue = 1 | pages = 51–60 | citeseerx = 10.1.1.462.255 | s2cid = 53446536 | archive-date = March 4, 2016 | access-date = August 6, 2018 | archive-url = https://web.archive.org/web/20160304002456/http://dinoweb.ucoz.ru/_fr/4/A_new_method_to.pdf | url-status = live }}</ref> Compared to other compsognathids, the larger French specimen would have been similar in size to larger ''[[Sinosauropteryx]]'' specimens, but smaller than ''[[Huaxiagnathus]]'' and ''[[Mirischia]]''.<ref name=peyer06/>

''Compsognathus'' were small, bipedal animals with long legs and longer tails, which they used for balance during locomotion. The forelimbs were smaller than the hindlimbs. The hand bore two large, clawed digits and a third, smaller digit that may have been non-functional.<ref name=peyer06/><ref name=gishlick07/> Their delicate skulls were narrow and long, with tapered snouts. The skull had five pairs of [[Fenestra (anatomy)|fenestrae]] (skull openings), the largest of which was for the [[Orbit (anatomy)|orbit]] (eye socket),<ref name="Lambert">{{cite book| last = Lambert| first = David| title = The Ultimate Dinosaur Book| publisher = Dorling Kindersley| year = 1993| location = New York| pages = [https://archive.org/details/ultimatedinosaur00lamb/page/38 38–81]| isbn = 978-1-56458-304-8| url = https://archive.org/details/ultimatedinosaur00lamb/page/38}}</ref>  with the eyes being larger in proportion to the rest of the skull. The lower jaw was slender and had no mandibular fenestra, a hole in the side of the lower jawbone commonly seen in [[archosaur]]s.

The teeth were small and pointed, suited for its diet of small vertebrates and possibly other small animals, such as insects. The German specimen had three teeth in each [[premaxilla]] (front bone of the lower jaw), 15 or 16 teeth in each maxilla, and 18 teeth in the lower jaw.<ref name="stromer1934">{{cite journal|last=Stromer| first=E. |year=1934 |title=Die Zähne des ''Compsognathus'' und Bemerkungen über das Gebiss der Theropoda |journal=Zentralblatt für Mineralogie, Geologie und Paläontologie, Abteilung B |volume=Jahrgang 1934| pages=74–85 |language=German}}</ref><ref name=ostrom78/> The French specimen had more teeth, including four in each premaxilla, 17 or 18 in the maxilla, and at least 21 teeth in the dentary.<ref name=peyer06/> Compsognathids were unique among theropods in having [[tooth crown]]s that curved backwards at two thirds of their height, while their mid-parts were straight; also, the crowns had expanded bases.<ref name=peyer06/> In ''Compsognathus'', the frontmost teeth of the upper and lower jaws were [[Serration|unserrated]], while those further back had fine serrations on their rear edges. In the German specimen, the crowns were around two times higher than wide in the front of the jaws but diminished in height further back, with the last tooth about as high as wide.<ref name="stromer1934"/> The German specimen also shows a [[diastema]] (tooth gap) behind the first three teeth of the premaxilla.<ref name=ostrom78/> As such a gap was not present in the French specimen, Peyer suggested that additional teeth were possibly present in this region the German specimen.<ref name=peyer06/>

The number of digits on the hand of ''Compsognathus'' has been a source of debate.<ref name=gishlick07/> For much of its history, ''Compsognathus'' was typically depicted with three digits, as is typical for theropods.<ref name=gishlick07/><ref name=ostrom78/> However, the type specimen only preserved phalanges from the first two digits, leading to the suggestion that ''Compsognathus'' had only two functional digits, with the third metacarpal being smaller and thinner.<ref name=ostrom78/> Study of the French specimen indicated that the third digit bore at least one or two small phalanges.<ref name=peyer06/><ref name=gishlick07/> However, there remains no evidence for an ungual phalanx on the third digit, so the digit may have been reduced and non-functional.<ref name=gishlick07/>

===Integument===
[[File:Compsognathus BW.jpg|thumb|Evidence from related species suggests that the body might have been covered with feather-like structures.]]
Some relatives of ''Compsognathus'', namely ''[[Sinosauropteryx]]'' and ''[[Sinocalliopteryx]]'', have been preserved with the remains of simple feathers covering the body like fur,<ref name="Currie2001"/> prompting some scientists to suggest that ''Compsognathus'' might have been feathered in a similar way.<ref name="jietal2007">{{cite journal | last1 = Ji | first1 = S. | last2 = Ji | first2 = Q. | last3 = Lu | first3 = J. | last4 = Yuan | first4 = C. | year = 2007 | title = A new giant compsognathid dinosaur with long filamentous integuments from Lower Cretaceous of Northeastern China | journal = Acta Geologica Sinica | volume = 81 | issue = 1| pages = 8–15 }}</ref> Consequently, many depictions of ''Compsognathus'' show them with coverings of downy proto-feathers. However, no feathers or feather-like covering have been preserved with ''Compsognathus'' fossils, in contrast to ''Archaeopteryx'', which are found in the same sediments. Karin Peyer, in 2006, reported skin impressions preserved on the side of the tail starting at the 13th tail vertebra. The impressions showed small bumpy tubercles, similar to the scales found on the tail and hind legs of ''[[Juravenator]]''.<ref name=peyer2006>{{cite journal | doi = 10.1671/0272-4634(2006)26[879:AROCFT]2.0.CO;2 | last1 = Peyer | first1 = K. | year = 2006 | title = A reconsideration of ''Compsognathus'' from the Upper Tithonian of Canjuers, southeastern France | journal = Journal of Vertebrate Paleontology | volume = 26 | issue = 4| pages = 879–896 | s2cid = 86338296 }}</ref> Additional scales had in 1901 been reported by Von Huene, in the abdominal region of the German ''Compsognathus'', but Ostrom subsequently disproved this interpretation;<ref name=ostrom78/><ref name="Huene01">{{cite journal |last= von Huene|first= F.|year=1901|title= Der vermuthliche Hautpanzer des "Compsognathus longipes" Wagner |journal=Neues Jahrbuch für Mineralogie, Geologie und Paläontologie |volume= 1|pages=157–160}}</ref> in 2012, Achim Reisdorf postulated that they are plaques of [[adipocere]], corpse wax.<ref name=reisdorf2012>{{cite journal | last1 = Reisdorf | first1 = A.G. | last2 = Wuttke | first2 = M. | year = 2012 | title = Re-evaluating Moodie's Opisthotonic-Posture Hypothesis in fossil vertebrates. Part I: Reptiles – The taphonomy of the bipedal dinosaurs ''Compsognathus longipes'' and ''Juravenator starki'' from the Solnhofen Archipelago (Jurassic, Germany) | journal = Palaeobiodiversity and Palaeoenvironments | volume = 92 | issue = 1| pages = 119–168 | doi = 10.1007/s12549-011-0068-y | s2cid = 129785393 }}</ref>

Like ''Compsognathus'', and unlike ''Sinosauropteryx'', a patch of fossilized skin from the tail and hindlimb of the possible relative ''[[Juravenator starki]]'' shows mainly scales, though there is some indication that simple feathers were also present in the preserved areas.<ref name=Goehlich2006>{{cite journal | last1 = Goehlich | first1 = U.B. | last2 = Tischlinger | first2 = H. | last3 = Chiappe | first3 = L.M. | year = 2006 | title = ''Juraventaor starki'' (Reptilia, Theropoda) ein nuer Raubdinosaurier aus dem Oberjura der Suedlichen Frankenalb (Sueddeutschland): Skelettanatomie und Wiechteilbefunde | journal = Archaeopteryx | volume = 24 | pages = 1–26 }}</ref> This may mean that a feather covering was not ubiquitous in this group of dinosaurs, or maybe that some species had fewer feathers than others.<ref>{{cite journal |last= Xu|first= Xing |year=2006|title= Palaeontology: Scales, feathers and dinosaurs |journal=Nature |volume= 440|issue=7082|pages=287–8 |doi=10.1038/440287a |pmid= 16541058 |bibcode = 2006Natur.440..287X |s2cid= 28376204 |doi-access= free }}</ref>