Editing Pterosaur (section)

===Extinction===
[[File:Arambourgiania_philadelphiae.png|thumb|left|[[Azhdarchid]] pterosaurs such as ''[[Arambourgiana]]'' thrived at the end of the Cretaceous]]
It was once thought that competition with early [[bird]] species might have resulted in the [[extinct]]ion of many of the pterosaurs.<ref>BBC Documentary: ''Walking with dinosaurs (episode 4 ) – Giant Of The Skies'' at 22', Tim Haines, 1999</ref> It was thought that by the end of the Cretaceous, only large species of pterosaurs were present (no longer true; see below). The smaller species were thought to have become extinct, their niche filled by birds.<ref>{{cite journal |vauthors=Slack KE, Jones CM, Ando T, etal |title=Early penguin fossils, plus mitochondrial genomes, calibrate avian evolution |journal=Molecular Biology and Evolution |volume=23 |issue=6 |pages=1144–55 |date=June 2006 |pmid=16533822 |doi=10.1093/molbev/msj124 |doi-access=free }}</ref> However, pterosaur decline (if actually present) seems unrelated to bird diversity, as ecological overlap between the two groups appears to be minimal.<ref>{{cite journal |title=Estimating the effects of sampling biases on pterosaur diversity patterns: implications for hypotheses of bird/pterosaur competitive replacement|journal=Paleobiology|issue=3|pages=432–46|year= 2009|author1=Butler, Richard J. |author2=Barrett, Paul M. |author3=Nowbath, Stephen |author4=Upchurch, Paul |name-list-style=amp |volume=35 |doi=10.1666/0094-8373-35.3.432|bibcode=2009Pbio...35..432B |s2cid=84324007}}</ref> In fact, at least some avian niches were reclaimed by pterosaurs prior to the [[Cretaceous–Paleogene extinction event]].<ref name="longrichetal2018"/> It seems that the K-Pg extinction event at the end of the Cretaceous, which wiped out all non-avian dinosaurs and many other animals, was the direct cause of the extinction of the pterosaurs.

Small-sized pterosaur species apparently were present in the [[Csehbánya Formation]], indicating a higher diversity of Late Cretaceous pterosaurs than previously accounted for.<ref>{{cite journal|author1=Prondvai, E. |author2=Bodor, E. R. |author3=Ösi, A. |year=2014 |title=Does morphology reflect osteohistology-based ontogeny? A case study of Late Cretaceous pterosaur jaw symphyses from Hungary reveals hidden taxonomic diversity |journal=Paleobiology |volume=40 |issue=2 |pages=288–321 |doi=10.1666/13030|bibcode=2014Pbio...40..288P |s2cid=85673254 |url=http://real.mtak.hu/21860/1/Prondvai_et_al.2014_reposit1_u_110445.946242.pdf }}</ref> The recent findings of a small [[cat]]-sized adult azhdarchid further indicate that small pterosaurs from the Late Cretaceous might actually have simply been rarely preserved in the fossil record, helped by the fact that there is a strong bias against terrestrial small sized vertebrates such as juvenile [[dinosaurs]], and that their diversity might actually have been much larger than previously thought.<ref>{{cite journal | last1 = Martin-Silverstone | first1 = Elizabeth | last2 = Witton | first2 = Mark P. | last3 = Arbour | first3 = Victoria M. | last4 = Currie | first4 = Philip J. | year = 2016 | title = A small azhdarchoid pterosaur from the latest Cretaceous, the age of flying giants | journal = Royal Society Open Science | volume = 3 | issue = 8| page = 160333 | doi = 10.1098/rsos.160333 | pmid = 27853614 | pmc = 5108964 | bibcode = 2016RSOS....360333M}}</ref>

A 2021 study showcases that niches previously occupied by small pterosaurs were increasingly occupied by the juvenile stages of larger species in the Late Cretaceous. Rather than being outcompeted by birds, pterosaurs essentially specialized a trend already occurring in previous eras of the Mesozoic.<ref name="Smith et al 2021">{{cite journal |last1=Smith |first1=Roy E. |last2=Chinsamy |first2=Anusuya |last3=Unwin |first3=David M. |last4=Ibrahim |first4=Nizar |last5=Zouhri |first5=Samir |last6=Martill |first6=David M. |title=Small, immature pterosaurs from the Cretaceous of Africa: implications for taphonomic bias and palaeocommunity structure in flying reptiles |journal=Cretaceous Research |date=16 October 2021 |volume=130 |pages=105061 |doi=10.1016/j.cretres.2021.105061 |s2cid=239257717 |url=https://figshare.com/articles/journal_contribution/20261157 }}</ref>