Editing Conodont (section)

== Evolutionary history ==
[[File:Conodonts.jpg|thumb|300px|Conodont elements from the Deer Valley Member of the [[Mauch Chunk Formation]] in Pennsylvania, Maryland, and West Virginia, US <br>{{hidden|detail|Figures 1, 2. Conodonts from the Deer Valley Member of the Mauch Chunk Formation, Keystone quarry, Pa. This collection (93RS–79c) is from the lower 10 cm of the Deer Valley Member. Note the nonabraded, although slightly broken, conodont elements of the high-energy oolitic marine facies of the Deer Valley Member.<br>1. ''[[Kladognathus]] sp.'', Sa element, posterior view, X140 2. ''[[Cavusgnathus]] unicornis'', gamma morphotype, Pa element, lateral view, X140 <br>3–9. Conodonts from the uppermost Loyalhanna Limestone Member of the Mauch Chunk Formation, Keystone quarry, Pa. This collection (93RS–79b) is from the upper 10 cm of the Loyalhanna Member. Note the highly abraded and reworked aeolian forms. <br>3, 4. ''[[Kladognathus]] sp.'', Sa element, lateral views, X140 <br>5. ''[[Cavusgnathus]] unicornis'', alpha morphotype, Pa element, lateral view, X140 <br>6, 7. ''[[Cavusgnathus]] sp.'', Pa element, lateral view, X140 <br>8. ''[[Polygnathus]] sp.'', Pa element, upper view, reworked Late Devonian to Early Mississippian morphotype, X140 <br>9. ''[[Gnathodus]] texanus?'', Pa element, upper view, X140 <br>10–14. Conodonts from the basal 20 cm of the Loyalhanna Limestone Member of the Mauch Chunk Formation, Keystone quarry, Pa. (93RS–79a), and Westernport, Md. (93RS–67), note the highly abraded and reworked aeolian forms <br>10. ''[[Polygnathus]] sp.'', Pa element, upper view, reworked Late Devonian to Early Mississippian morphotype, 93RS–79a, X140 <br>11. ''Polygnathus sp.'', Pa element, upper view, reworked Late Devonian to Early Mississippian morphotype, 93RS–67, X140 <br>12. ''[[Gnathodus]] sp.'', Pa element, upper view, reworked Late Devonian(?) through Mississippian morphotype, 93RS–67, X140 <br>13. ''[[Kladognathus]] sp.'', M element, lateral views, 93RS–67, X140 <br>14. ''[[Cavusgnathus]] sp.'', Pa element, lateral view, 93RS–67, X140}}]]The earliest fossils of conodonts are known from the Cambrian period. Conodonts extensively diversified during the early Ordovician, reaching their apex of diversity during the middle part of the period, and experienced a sharp decline during the late Ordovician and Silurian, before reaching another peak of diversity during the mid-late Devonian. Conodont diversity declined during the [[Carboniferous]], with an extinction event at the end of the middle [[Tournaisian]]<ref>{{cite journal |last1=Zhuravlev |first1=Andrey V. |last2=Plotitsyn |first2=Artem N. |date=18 January 2022 |title=The middle–late Tournaisian crisis in conodont diversity: a comparison between Northeast Laurussia and Northeast Siberia |url=https://www.sciencedirect.com/science/article/abs/pii/S1871174X22000014 |journal=Palaeoworld |volume=31 |issue=4 |pages=633–645 |doi=10.1016/j.palwor.2022.01.001 |s2cid=246060690 |access-date=16 October 2022}}</ref> and a prolonged period of significant loss of diversity during the [[Pennsylvanian (geology)|Pennsylvanian]].<ref name="Shi-2021">{{cite journal |last1=Shi |first1=Yukun |last2=Wang |first2=Xiangdong |last3=Fan |first3=Junxuan |last4=Huang |first4=Hao |last5=Xu |first5=Huiqing |last6=Zhao |first6=Yingying |last7=Shen |first7=Shuzhong |date=September 2021 |title=Carboniferous-earliest Permian marine biodiversification event (CPBE) during the Late Paleozoic Ice Age |url=https://www.sciencedirect.com/science/article/pii/S0012825221002002 |journal=Earth-Science Reviews |volume=220 |page=103699 |doi=10.1016/j.earscirev.2021.103699 |bibcode=2021ESRv..22003699S |access-date=4 September 2022}}</ref><ref>{{cite journal |last1=Sepkoski |first1=J. J. |year=2002 |title=A compendium of fossil marine animal genera |journal=Bulletins of American Paleontology |volume=363 |pages=1–560}}</ref> Only a handful of conodont genera were present during the Permian, though diversity increased after the P-T extinction during the Early Triassic.

Diversity continued to decline during the Middle and Late Triassic, culminating in their extinction soon after the Triassic-Jurassic boundary. Much of their diversity during the Paleozoic was likely controlled by sea levels and temperature, with the major declines during the Late Ordovician and Late Carboniferous due to cooler temperatures, especially [[glacial event]]s and associated [[marine regression]]s which reduced [[continental shelf]] area. However, their final demise is more likely related to [[biotic interactions]], perhaps competition with new Mesozoic taxa.<ref>{{Cite journal|last1=Ginot|first1=Samuel|last2=Goudemand|first2=Nicolas|date=December 2020|title=Global climate changes account for the main trends of conodont diversity but not for their final demise|journal=Global and Planetary Change|language=en|volume=195|pages=103325|doi=10.1016/j.gloplacha.2020.103325|bibcode=2020GPC...19503325G|s2cid=225005180|doi-access=free}}</ref>