Editing Reptile (section)

===Mesozoic reptiles===
The close of the Permian saw the greatest mass extinction known (see the [[Permian–Triassic extinction event]]), an event prolonged by the combination of two or more distinct extinction pulses.<ref name="SahneyBenton2008RecoveryFromProfoundExtinction">{{cite journal |author1=Sahney, S. |author2=Benton, M.J.  |name-list-style=amp | year=2008 | title=Recovery from the most profound mass extinction of all time | journal=Proceedings of the Royal Society B | doi=10.1098/rspb.2007.1370 |doi-access=free | volume = 275 | pages = 759–765| pmid=18198148 | issue=1636 | pmc=2596898}}</ref> Most of the earlier parareptile and synapsid megafauna disappeared, being replaced by the true reptiles, particularly [[archosauromorpha|archosauromorphs]]. These were characterized by elongated hind legs and an erect pose, the early forms looking somewhat like long-legged crocodiles. The [[archosaur]]s became the dominant group during the [[Triassic]] period, though it took 30 million years before their diversity was as great as the animals that lived in the Permian.<ref name="SahneyBenton2008RecoveryFromProfoundExtinction"/> Archosaurs developed into the well-known [[dinosaur]]s and [[pterosaur]]s, as well as the ancestors of [[crocodile]]s. Since reptiles, first [[rauisuchia]]ns and then dinosaurs, dominated the Mesozoic era, the interval is popularly known as the "Age of Reptiles". The dinosaurs also developed smaller forms, including the feather-bearing smaller [[theropoda|theropods]]. In the [[Cretaceous]] period, these gave rise to the first true [[birds]].<ref name=divergence>{{Cite journal | last1 = Lee | first1 = Michael SY | last2 = Cau | first2 = Andrea | last3 = Darren | first3 = Naish | last4 = Gareth J. | first4 = Dyke | year = 2013 | title = Morphological Clocks in Paleontology, and a Mid-Cretaceous Origin of Crown Aves | journal = Systematic Biology | doi = 10.1093/sysbio/syt110 |doi-access=free | pmid=24449041 | volume=63 | issue = 3 | pages=442–449}}</ref>

The [[sister group]] to Archosauromorpha is [[Lepidosauromorpha]], containing [[lizard]]s and [[tuatara]]s, as well as their fossil relatives. Lepidosauromorpha contained at least one major group of the Mesozoic sea reptiles: the [[mosasaurs]], which lived during the [[Cretaceous]] period. The phylogenetic placement of other main groups of fossil sea reptiles – the [[ichthyopterygia]]ns (including [[ichthyosaur]]s) and the [[sauropterygia]]ns, which evolved in the early Triassic – is more controversial. Different authors linked these groups either to lepidosauromorphs<ref name=Gauthier-1994-Prothero-Schoch>{{cite book |author=Gauthier, J.A. |year=1994 |section=The diversification of the amniotes |editor1=Prothero, D.R. |editor2=Schoch, R.M. |title=Major Features of Vertebrate Evolution |journal=Short Courses in Paleontology |volume=7 |pages=129–159 |place=Knoxville, TN |publisher=The Paleontological Society |doi=10.1017/S247526300000129X |chapter-url=https://www.cambridge.org/core/journals/short-courses-in-paleontology/article/abs/diversification-of-the-amniotes/EDBFD2920CC4B45A0BB6299C8B787F90 }}</ref> or to archosauromorphs,<ref>{{Cite journal |author=Merck, John W. |year=1997 |title=A phylogenetic analysis of the euryapsid reptiles |journal=Journal of Vertebrate Paleontology |volume=17 |issue=Supplement to 3 |pages=1–93|doi=10.1080/02724634.1997.10011028}}</ref><ref>{{cite conference |author1=Modesto, Sean |author2=Reisz, Robert |author3=Scott, Diane |year=2011 |title=A neodiapsid reptile from the Lower Permian of Oklahoma |conference=71st Annual Meeting |publisher=Society of Vertebrate Paleontology |series=Program and Abstracts |page=160}}</ref><ref>{{cite web |author=Holtz, T. |title=Fossil tetrapods |series=GEOL&nbsp;331 Vertebrate Paleontology&nbsp;II |type=class handouts |website=geol.umd.edu |publisher=[[University of Maryland]], Department of Geology |url=http://www.geol.umd.edu/~tholtz/G331/lectures/331vertsII.html}}</ref> and ichthyopterygians were also argued to be diapsids that did not belong to the least inclusive clade containing lepidosauromorphs and archosauromorphs.<ref>{{cite journal |author1=Motani, Ryosuke |author2=Minoura, Nachio |author3=Ando, Tatsuro |year=1998 |title=Ichthyosaurian relationships illuminated by new primitive skeletons from Japan |journal=[[Nature (journal)|Nature]] |volume=393 |issue=6682 |pages=255–257 |doi=10.1038/30473 |bibcode=1998Natur.393..255M |s2cid=4416186 }}</ref>