Six Great Extinction Events

The Six Great Extinctions Extinction is just another word used for the dying off of one species or of many species. Since the beginning of time there have been five mass extinction and then some smaller extinctions. Either big or small, they play a huge role in the evolution of the species around us. Whether they were a common ancestor, or a close relative to an organism, they still helped the organisms we know today evolve and adapt to the environment that we now share. During the extinction events some species are more probable to survive than others are (Futuyma 173). Amphibians have survived through many of the great extinctions (Kolbert, 2009). They once were an all marine organism but have evolved throughout time and now can live on …show more content…
The end Permian event took place about 251 million years ago, and on the species level about 96% marine species were lost and over 70% of terrestrial species were lost (“Permian Extinction”, 2015) (Murcia, 2015). During this extinction event, there were many organisms that disappeared but did not go extinct. They merely disappeared, but the reappeared again during the middle to late Triassic period (Erwin, 1990). There were also organisms that slowly started disappearing at the beginning of the Permian: the corals and other organisms like the corals (Erwin, 1990). Different groups during this time started declining at different times, so a time scale is hard to put together for this extinction event (Erwin, 1990). There is still today much debate about how all of this happened. Some scientists say that it was a very slow and progressive event (Erwin, 1990), while others say that it was rapid and lasted only about 200,000 years (“Permian Extinction”, 2015). Unlike the two events prior, there are many speculations as to what could have caused this extinction event. The newest research that is out says that it could be because of the Methanosarcina that belong to the Archean’s (“Permian Extinction”, 2015). This particular group evolved the ability to produce methane, which could have led to the increase in water temperatures (“Permian Extinction”, 2015). With the methane being produced it could have also disrupted the other atmospheric cycle, meaning that less photosynthesis was taking place and that there were fewer oxygen counts in the waters as well (“Permian Extinction”, 2015). Only the organisms that were adapted to living in this environment could have survived (“Permian Extinction”, 2015). Not only were the marine organisms effected by this event, but also the aquatic and terrestrial life as well (Erwin, 1990). Another theory as to why this took place is that when the