The Permian is a geological period that lasted from 298.9 to 252.2 million years ago. It was the last period of the Paleozoic Era, and saw the mass extinction of many species known as The Great Dying. The Permian Period began with the Collision of Pangea I, which resulted in the formation of Pangea II. This supercontinent included all of today’s continents except for Antarctica and Australia. During the Permian, there were four main climatic zones: equatorial, northern temperate, southern temperate, and polar. These climate zones were determined by latitude; however, they were also affected by elevation (higher elevations being cooler) and proximity to large bodies of water (which tend to moderate temperatures).
At the start of the Permian, life was flourishing on Earth. The oceans were teeming with fish, invertebrates, and marine reptiles. On land, arthropods such as millipedes and cockroaches scuttled among plants including ferns, cycads, ginkgoes, and seed ferns. Amphibians such as frogs hopped among these plants while lizards sunned themselves on rocks or hunted for small prey. Early tetrapods such as Seymouria walked across floodplains searching for food such as insects or carrion. In the skies above them flew pterosaurs such as Rhamphorhynchus and Dimorphodon . All of these animals were relatively small; however this would change during the Permian as some lineages began to produce giant members.
One example is “therapsids” – a group that includes mammals and their extinct relatives – which gave rise to creatures such as Titanophoneus , a 6 meter long carnivore with teeth up to 10 cm long! Another example is “sauropodomorph” dinosaurs which include Apatosaurus and Brachiosaurus ; both groups would continue to grow in size throughout the Mesozoic Era until their ultimate demise 65 million years ago at the end-Cretaceous mass extinction event . But even before then, during the Permian itself another mass extinction occurred – The Great Dying – which killed off around 96% of all marine species and 70% of terrestrial vertebrate species . No one knows exactly what caused this event , but it marks a turning point in Earth’s history after which life would never be quite so diverse again .
So what happened during this time? And why did things change so much afterwards? Let’s take a closer look…
During the early part ofPermiantime , conditions were favourableforlifeonEarthwithwarmtemperaturesandhigh levels o CO2in theatmosphere providing plentyofplantfoodandconducivetoclimateswherelife could flourishonlandandinsea . However , there weresignsofchangeonthe horizonasasteadydeclineinoceanoxygenlevelsbegantooccuraround 280 mya(millionyearsago) . This trendwouldcontinueuntilOxygenlevelswereatcritical lowsbytheendoftheperiod 252 myaandmanymarineanimalssuchasshrimps , crabs squidwereunabletosurviveinthenewly anoxic conditionscausedbyexcessively high levels ofthesedissolvedgasesso perished . Inadditionto changesinthewater columnanoxiawasalsoseeninfossilrecordsofthemudflatsdepositedontheseafloorwhich showedaminimaldiversityoffauna mismatchedtotheexuberantdiversityoffauna seenpreviouslyduringearlierpartsofthePalaeozoicEra Theselow levelsofofficiallysignalledthebeginningofmassextinctioneventknownasTheGreatDyingorTheEndPermiandMassExtinctionEventwhicheventuallywipedoutapproximately96 %ofmarinespeciesand70 %oterrestrialvertebratespeciesoveraperiodoftens milionyearsfrom252 2myato 251 2myaThis madeitextinctioseventisarguably themostdevastatingbiologicaldisasterinEarthshistorywith farreachingconsequencesforlifeto come