Editing Extinction event (section)

====Plate tectonics====
Movement of the continents into some configurations can cause or contribute to extinctions in several ways: by initiating or ending [[ice age]]s; by changing ocean and wind currents and thus altering climate; by opening seaways or land bridges that expose previously isolated species to competition for which they are poorly adapted (for example, the extinction of most of South America's [[Meridiungulata|native ungulates]] and all of its [[Sparassodonta|large metatherians]] after the [[Great American Interchange|creation of a land bridge between North and South America]]). Occasionally continental drift creates a super-continent that includes the vast majority of Earth's land area, which in addition to the effects listed above is likely to reduce the total area of [[continental shelf]] (the most species-rich part of the ocean) and produce a vast, arid continental interior that may have extreme seasonal variations.

Another theory is that the creation of the super-continent [[Pangaea]] contributed to the [[Permian-Triassic extinction event|End-Permian]] mass extinction. Pangaea was almost fully formed at the transition from mid-Permian to late-Permian, and the "Marine genus diversity" diagram at the top of this article shows a level of extinction starting at that time, which might have qualified for inclusion in the "Big Five" if it were not overshadowed by the "Great Dying" at the end of the Permian.<ref>{{cite web |title=Speculated Causes of the Permian Extinction |publisher=Hooper Virtual Paleontological Museum |url=http://park.org/Canada/Museum/extinction/permcause.html |access-date=16 July 2012}}</ref>