Editing Tethys Ocean (section)

==Modern theory==
{{More citations needed section|date=April 2025}}
From the [[Ediacaran]] (600&nbsp;{{abbr|Mya|million years ago}}) into the [[Devonian]] (360 {{abbr|Mya|million years ago}}), the [[Proto-Tethys Ocean]] existed and was situated between [[Baltica]] and [[Laurentia]] to the north and [[Gondwana]] to the south.

From the [[Silurian]] (440 {{abbr|Mya|million years ago}}) through the [[Jurassic]] periods, the Paleo-Tethys Ocean existed between the [[Hunic terranes]] and Gondwana. Over a period of 400&nbsp;million years, continental [[terrane]]s intermittently separated from Gondwana in the Southern Hemisphere to migrate northward to form Asia in the Northern Hemisphere.<ref name=metcalfe>{{Harvnb|Metcalfe|2013|loc=Introduction, p. 2}}</ref>[[File:249 global.png|thumb|Plate tectonic reconstruction of the Tethys realm at 249&nbsp;{{abbr|Mya|million years ago}}]]
===Triassic Period===
About 250&nbsp;Mya,<ref>{{cite web |url=http://www.palaeos.com/Mesozoic/Triassic/MidTrias.html |series=Palaeos Mesozoic: Triassic |title=Middle Triassic |archive-url=https://web.archive.org/web/20080516030745/http://www.palaeos.com/Mesozoic/Triassic/MidTrias.html |archive-date=May 16, 2008 |df=dmy-all}}</ref> during the [[Triassic]], a new ocean began forming in the southern end of the Paleo-Tethys Ocean. A rift formed along the northern continental shelf of Southern [[Pangaea]] (Gondwana). Over the next 60&nbsp;million years, that piece of shelf, known as [[Cimmerian plate|Cimmeria]], traveled north, pushing the floor of the Paleo-Tethys Ocean under the eastern end of northern [[Pangaea]] (early / proto- [[Laurasia]]). The Neo-Tethys Ocean formed between Cimmeria and Gondwana, directly over where the Paleo-Tethys formerly rested.{{citation needed|date=June 2017}}

===Jurassic Period===
During the [[Jurassic]] period about 150&nbsp;Mya, Cimmeria finally collided with Laurasia and stalled, so the ocean floor behind it [[subduction|buckled under]], forming the [[Tethys Trench]]. Water levels rose, and the western Tethys shallowly covered significant portions of Europe, forming the first Tethys Sea. Around the same time, Laurasia and Gondwana began [[continental drift|drifting apart]], opening an extension of the Tethys Sea between them which today is the part of the Atlantic Ocean between the [[Mediterranean]] and the [[Caribbean]]. As North and South America were still attached to the rest of Laurasia and Gondwana, respectively, the Tethys Ocean in its widest extension was part of a continuous oceanic belt running around the Earth between about [[latitude]] 30°N and the [[Equator]]. Thus, [[ocean current]]s at the time around the [[Early Cretaceous]] ran very differently from the way they do today.{{citation needed|date=June 2017}}

===Late Cretaceous===
[[File:100 global.png|thumb|Plate tectonic reconstruction of the Tethys realm at 100&nbsp;Mya]]
Between the Jurassic and the [[Late Cretaceous]], which started about 100  Mya, Gondwana began breaking up, pushing Africa and India north across the Tethys and opening up the Indian Ocean. During the Late Cretaceous the Tethys sea was home to many different animals, including [[marine reptiles]], [[Osteichthyes|bony fish]], [[Chondrichthyes|cartilaginous fish]] and [[Cephalopod|cephalopods]]. The [[Island|islands]] that were located in the northern parts of the Tethys sea ([[Europe]]) created [[Biodiversity|biodiverse]] [[Ecosystem|ecosystems]] that had animals that went through [[insular dwarfism]] and [[Island gigantism|insular gigantism]]. The insular dwarfism process happened mostly to the [[Dinosaur|dinosaurs]] that lived on the islands, like the [[Sauropoda|sauropods]] and the [[Hadrosauromorpha|hadrosaurs]]. [[Telmatosaurus]] is a good representation of the insular dwarfism process. While the insular dwarfism process happened to the dinosaurs, the [[Pterosaur|pterosaurs]] that lived on the islands went through the process known as insular gigantism. [[Hatzegopteryx]] was a huge [[Azhdarchidae|azhdarchid]] pterosaur that lived on the islands of the Tethys sea, this giant pterosaur would have filled it's [[ecological niche]] as [[apex predator]]. During the [[Maastrichtian]] the Tethys sea had many different large mosasaurs that lived in the same geographical area and would have competed with each other. Europe had large mosasaurs like [[Prognathodon|Prognathodon giganteus]], Prognathodon saturator, Prognathodon sectorius, [[Mosasaurus|Mosasaurus hoffmannii]] and Mosasaurus lemonnieri. [[North Africa]] would have also had large mosasaurs like Prognathodon giganteus, Prognathodon currii, [[Thalassotitan|Thalassotitan atrox]], [[Hainosaurus boubker]] and Mosasaurus beaugei. The competition between many different apex predators is something we don't only see in the Tethys sea, we also see this in the [[Western Interior Seaway]].{{Citation needed|date=April 2025}}

===Cenozoic===
[[File:Dire Straits FIG 01.jpg|thumb|Vast regions of Europe and west-central Asia were still covered by a contiguous Tethys at the start of the [[Eocene]] (top image), but by the Oligocene, most of this had dried out (bottom image), and the Tethys was almost entirely divided into the Indian Ocean, Mediterranean and Paratethys.]]
Throughout the [[Cenozoic]] (66 million to the dawn of the Neogene, 23&nbsp;Mya), the connections between the Atlantic and Indian Oceans across the Tethys were eventually closed off in what is now the Middle East during the [[Miocene]], as a consequence of the northern migration of Africa/Arabia and global sea levels falling due to the concurrent formation of the [[Antarctic ice sheet|Antarctic Ice Sheet]]. This decoupling occurred in two steps, first around 20 Mya and another around 14&nbsp;Mya.<ref name=":1" /> The complete closure of the Tethys led to a global reorganization of currents, and is what is thought to have allowed for [[upwelling]] in the [[Arabian Sea]] and led to the establishment of the modern [[Monsoon of South Asia|South Asian Monsoon]]. It also caused major modifications to the functioning of the [[Atlantic meridional overturning circulation|AMOC]] and [[Antarctic Circumpolar Current|ACC]].<ref name=":1" />

During the [[Oligocene]] (33.9 to 23  Mya), large parts of central and eastern Europe were covered by a northern branch of the Tethys Ocean, called the [[Paratethys]]. The Paratethys was separated from the Tethys with the formation of the Alps, [[Carpathians]], [[Dinarides]], [[Taurus Mountains|Taurus]], and [[Elburz]] mountains during the [[Alpine orogeny]]. During the late [[Miocene]], the Paratethys gradually disappeared, and became an isolated inland sea.<ref>{{cite journal 
 |last1=Steininger |first1=F.F.
 |last2=Wessely|first2=G.
 |title= From the Tethyan Ocean to the Paratethys Sea: Oligocene to Neogene stratigraphy, paleogeography and paleobiogeography of the circum-Mediterranean region and the Oligocene to Neogene Basin evolution in Austria
 |year = 2000|journal=Mitteilungen der Österreichischen Geologischen Gesellschaft |volume=92|pages=95–116}}</ref> Separation from the wider Tethys during the early Miocene initially led to a boost in [[Primary production|primary productivity]] for the Paratethys, but this gave way to a total ecosystem collapse during the late Miocene as a result of rapid dissolution of [[carbonate]].<ref name=":2" />