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103-514: The highest point of the Donnersberg is the rock Königstuhl ("king's seat") at 687 metres above sea level. The mountain has a diameter of about 7 kilometres and covers an area of some 2,400 hectares. The Donnersberg was formed by volcanic activity during the Permian , in the transition period between the lower and upper Rotliegend strata. The name Donnersberg is thought to refer to Donar ,

206-901: A century after its original naming, with the United States Geological Survey until 1941 considering the Permian a subsystem of the Carboniferous equivalent to the Mississippian and Pennsylvanian . The Permian Period is divided into three epochs , from oldest to youngest, the Cisuralian, Guadalupian, and Lopingian. Geologists divide the rocks of the Permian into a stratigraphic set of smaller units called stages , each formed during corresponding time intervals called ages. Stages can be defined globally or regionally. For global stratigraphic correlation,

309-630: A city in Perm Krai. The stage was introduced by Alexandr Antonovich Stukenberg in 1890. The Kungurian currently lacks a defined GSSP. Recent proposals have suggested the appearance of Neostreptognathodus pnevi as the lower boundary. The Guadalupian Series is named after the Guadalupe Mountains in Texas and New Mexico, where extensive marine sequences of this age are exposed. It was named by George Herbert Girty in 1902. The Roadian

412-630: A coal swamp community, has an upper canopy consisting of lycopsid tree Sigillaria , with a lower canopy consisting of Marattialean tree ferns, and Noeggerathiales. Early conifers appeared in the Late Carboniferous, represented by primitive walchian conifers, but were replaced with more derived voltzialeans during the Permian. Permian conifers were very similar morphologically to their modern counterparts, and were adapted to stressed dry or seasonally dry climatic conditions. The increasing aridity, especially at low latitudes, facilitated

515-541: A dramatic increase in diversification during the Early Permian. Towards the end of the Permian, there was a substantial drop in both origination and extinction rates. The dominant insects during the Permian Period were early representatives of Paleoptera , Polyneoptera , and Paraneoptera . Palaeodictyopteroidea , which had represented the dominant group of insects during the Carboniferous, declined during

618-406: A lineage of the eucynodont suborder. Biarmosuchia Dinocephalia Anomodontia Gorgonopsia Therocephalia Cynodontia Six major groups of therapsids are generally recognized: Biarmosuchia , Dinocephalia , Anomodontia , Gorgonopsia , Therocephalia and Cynodontia . A clade uniting therocephalians and cynodonts, called Eutheriodontia , is well supported, but relationships among

721-403: A mutation in the regulatory gene Msx2, which is involved in both the closure of the skull roof and the maintenance of hair follicles in mice. This suggests that hair may have first evolved in probainognathians, though it does not entirely rule out an earlier origin of fur. Whiskers probably evolved in probainognathian cynodonts. Some studies had inferred an earlier origin for whiskers based on

824-481: A peak of diversity in the Cisuralian, with a substantial decline during the Guadalupian-Lopingian following Olson's extinction, with the family diversity dropping below Carboniferous levels. Embolomeres , a group of aquatic crocodile-like limbed vertebrates that are reptilliomorphs under some phylogenies. They previously had their last records in the Cisuralian, are now known to have persisted into

927-525: A protective cover, over plants such as ferns that disperse spores in a wetter environment. The first modern trees ( conifers , ginkgos and cycads ) appeared in the Permian. Three general areas are especially noted for their extensive Permian deposits—the Ural Mountains (where Perm itself is located), China, and the southwest of North America, including the Texas red beds. The Permian Basin in

1030-642: Is a global hiatus in the terrestrial fossil record during the late Kungurian and early Roadian , referred to as "Olson's Gap" that obscures the nature of the transition. Other proposals have suggested that the North American and Russian records overlap, with the latest terrestrial North American deposition occurring during the Roadian, suggesting that there was an extinction event, dubbed " Olson's Extinction ". The Middle Permian faunas of South Africa and Russia are dominated by therapsids, most abundantly by

1133-663: Is defined by the first appearance of the conodont Jinogondolella aserrata. The Capitanian is named after the Capitan Reef in the Guadalupe Mountains of Texas, named by George Burr Richardson in 1904, and first used in a chronostratigraphic sense by Glenister and Furnish in 1961 as a substage of the Guadalupian Stage. The Capitanian was ratified as an international stage by the ICS in 2001. The GSSP for

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1236-476: Is poorly known, and there are few fossils that provide direct evidence for the presence or absence of fur. The most basal synapsids with unambiguous direct evidence of fur are docodonts , which are mammaliaforms very closely related to crown-group mammals. Two "mummified" juvenile specimens of the dicynodont Lystrosaurus murrayi preserve skin impressions; the skin is hairless, leathery, and dimpled, somewhat comparable to elephant skin. Fossilized facial skin from

1339-427: Is poorly understood. Most Permian therapsids had a pineal foramen, indicating that they had a parietal eye like many modern reptiles and amphibians. The parietal eye serves an important role in thermoregulation and the circadian rhythm of ectotherms, but is absent in modern mammals, which are endothermic . Near the end of the Permian, dicynodonts, therocephalians and cynodonts show parallel trends towards loss of

1442-452: Is thought to have existed during the Early Permian. Though the fossil record is fragmentary, lungfish appear to have undergone an evolutionary diversification and size increase in freshwater habitats during the Early Permian, but subsequently declined during the middle and late Permian. Conodonts experienced their lowest diversity of their entire evolutionary history during the Permian. Permian chondrichthyan faunas are poorly known. Members of

1545-629: The Carnian (Late Triassic), although they continued for some time longer in the wet equatorial band and the south. Some exceptions were the still further derived eucynodonts . At least three groups of them survived. They all appeared in the Late Triassic period. The extremely mammal -like family, Tritylodontidae , survived into the Early Cretaceous . Another extremely mammal-like family, Tritheledontidae , are unknown later than

1648-599: The International Commission on Stratigraphy (ICS) ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype ) identifying the lower boundary of the stage. The ages of the Permian, from youngest to oldest, are: For most of the 20th century, the Permian was divided into the Early and Late Permian, with the Kungurian being the last stage of

1751-588: The Königstuhl rock, a 27 metres tall tower was constructed in 1864–1865, the Ludwigsturm . After World War II , a radio mast for the largest U.S. radio station in western Europe was placed on the Donnersberg. In the early 1960s, a new communications tower was constructed, stretching over 200 metres. The Donnersbergbahn is a railway line that runs from Alzey to Kirchheimbolanden. The line originally ran even further, to Marnheim , but on March 20, 1945,

1854-738: The Late Triassic , the dicynodonts , became extinct towards the end of the period. The last surviving group of non-mammaliaform cynodonts were the Tritylodontidae , which became extinct during the Early Cretaceous . Therapsids' temporal fenestrae were larger than those of the pelycosaurs. The jaws of some therapsids were more complex and powerful, and the teeth were differentiated into frontal incisors for nipping, great lateral canines for puncturing and tearing, and molars for shearing and chopping food. Therapsid legs were positioned more vertically beneath their bodies than were

1957-726: The North China Craton , the South China Block and Indochina fused to each other and Pangea by the end of the Permian. The Zechstein Sea , a hypersaline epicontinental sea , existed in what is now northwestern Europe. Large continental landmass interiors experience climates with extreme variations of heat and cold (" continental climate ") and monsoon conditions with highly seasonal rainfall patterns. Deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms , plants with seeds enclosed in

2060-704: The Paleo-Tethys Ocean , a large ocean that existed between Asia and Gondwana. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia , causing the Paleo-Tethys Ocean to shrink. A new ocean was growing on its southern end, the Neotethys Ocean , an ocean that would dominate much of the Mesozoic Era. A magmatic arc, containing Hainan on its southwesternmost end, began to form as Panthalassa subducted under

2163-825: The Permian–Triassic extinction event (colloquially known as the Great Dying), the largest mass extinction in Earth's history (which is the last of the three or four crises that occurred in the Permian), in which nearly 81% of marine species and 70% of terrestrial species died out, associated with the eruption of the Siberian Traps . It took well into the Triassic for life to recover from this catastrophe; on land, ecosystems took 30 million years to recover. Prior to

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2266-537: The Pfrimm Viaduct , a railway bridge between Kirchheimbolanden and Marnheim, was destroyed by withdrawing German troops, and it has not been rebuilt since. Permian The Permian ( / ˈ p ɜːr m i . ə n / PUR -mee-ən ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago (Mya), to

2369-549: The Sydney Basin , and palaeoclimatic models of the Earth's climate based on the behaviour of modern weather patterns showing that such a megamonsoon would occur given the continental arrangement of the Permian. The aforementioned increasing equatorial aridity was likely driven by the development and intensification of this Pangaean megamonsoon. Permian marine deposits are rich in fossil mollusks , brachiopods , and echinoderms . Brachiopods were highly diverse during

2472-540: The Theriodontia . Hopson and Barghausen did not initially come to a conclusion about how dinocephalians, anomodonts and theriodonts were related to each other, but subsequent studies suggested that anomodonts and theriodonts should be classified together as the Neotherapsida. However, there remains debate over these relationships; in particular, some studies have suggested that anomodonts, not gorgonopsians, are

2575-447: The U.S. states of Texas and New Mexico is so named because it has one of the thickest deposits of Permian rocks in the world. Sea levels dropped slightly during the earliest Permian (Asselian). The sea level was stable at several tens of metres above present during the Early Permian, but there was a sharp drop beginning during the Roadian, culminating in the lowest sea level of the entire Palaeozoic at around present sea level during

2678-399: The Ural Mountains in the years 1840 and 1841. Murchison identified "vast series of beds of marl , schist , limestone , sandstone and conglomerate" that succeeded Carboniferous strata in the region. Murchison, in collaboration with Russian geologists, named the period after the surrounding Russian region of Perm, which takes its name from the medieval kingdom of Permia that occupied

2781-401: The dinocephalians , the herbivorous anomodonts , the carnivorous biarmosuchians , and the mostly carnivorous theriodonts . After a brief burst of evolutionary diversity, the dinocephalians died out in the later Middle Permian ( Guadalupian ) but the anomodont dicynodonts as well as the theriodont gorgonopsians and therocephalians flourished, being joined at the very end of the Permian by

2884-577: The pseudosuchians , dinosaurs , and pterosaurs in the following Triassic, first appeared and diversified during the Late Permian, including the first appearance of the Archosauriformes during the latest Permian. Cynodonts , the group of therapsids ancestral to modern mammals , first appeared and gained a worldwide distribution during the Late Permian. Another group of therapsids, the therocephalians (such as Lycosuchus ), arose in

2987-566: The sauropsids ( reptiles ). The world at the time was dominated by the supercontinent Pangaea , which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa . The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. Various authors recognise at least three, and possibly four extinction events in

3090-605: The Asselian, Sakmarian, and Artinskian stages. The Kungurian was later added to conform to the Russian "Lower Permian". Albert Auguste Cochon de Lapparent in 1900 had proposed the "Uralian Series", but the subsequent inconsistent usage of this term meant that it was later abandoned. The Asselian was named by the Russian stratigrapher V.E. Ruzhenchev in 1954, after the Assel River in the southern Ural Mountains. The GSSP for

3193-691: The Cisuralian. Another cool period began around the middle Capitanian. This cool period, lasting for 3-4 Myr, was known as the Kamura Event. It was interrupted by the Emeishan Thermal Excursion in the late part of the Capitanian, around 260 million years ago, corresponding to the eruption of the Emeishan Traps . This interval of rapid climate change was responsible for the Capitanian mass extinction event. During

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3296-450: The Cisuralian. Permian synapsids included some large members such as Dimetrodon . The special adaptations of synapsids enabled them to flourish in the drier climate of the Permian and they grew to dominate the vertebrates. A faunal turnover occurred around the transition between the Cisuralian and Guadalupian, with the decline of amphibians and the replacement of pelycosaurs (a paraphyletic group) with more advanced therapsids , although

3399-676: The Early Jurassic . Mammaliaformes was the third group, including Morganucodon and similar animals. Some taxonomists refer to these animals as "mammals", though most limit the term to the mammalian crown group . The non-eucynodont cynodonts survived the Permian–Triassic extinction; Thrinaxodon , Galesaurus and Platycraniellus are known from the Early Triassic . By the Middle Triassic , however, only

3502-500: The Early Permian Chemnitz petrified forest of Germany demonstrates that they had complex branching patterns similar to modern angiosperm trees. By the Late Permian, high thin forests had become widespread across the globe, as evidenced by the global distribution of weigeltisaurids. The oldest likely record of Ginkgoales (the group containing Ginkgo and its close relatives) is Trichopitys heteromorpha from

3605-534: The Early Permian of the United States has been hypothesized to be an even earlier-diverging therapsid, but more recent study has suggested it is more likely to be a non-therapsid sphenacodontian. Biarmosuchia is the most recently recognized therapsid clade, first recognized as a distinct lineage by Hopson and Barghausen in 1986 and formally named by Sigogneau-Russell in 1989. Most biarmosuchians were previously classified as gorgonopsians. Biarmosuchia includes

3708-599: The Early Permian. Glenister and colleagues in 1992 proposed a tripartite scheme, advocating that the Roadian-Capitanian was distinct from the rest of the Late Permian, and should be regarded as a separate epoch. The tripartite split was adopted after a formal proposal by Glenister et al. (1999). Historically, most marine biostratigraphy of the Permian was based on ammonoids ; however, ammonoid localities are rare in Permian stratigraphic sections, and species characterise relatively long periods of time. All GSSPs for

3811-568: The Early Triassic, but a Permian origin is suspected. The diversity of coelacanths is relatively low throughout the Permian in comparison to other marine fishes, though there is an increase in diversity during the terminal Permian (Changhsingian), corresponding with the highest diversity in their evolutionary history during the Early Triassic. Diversity of freshwater fish faunas was generally low and dominated by lungfish and "Paleopterygians". The last common ancestor of all living lungfish

3914-705: The Germanic god of thunder, a theory supported by the fact that the Romans dubbed the Donnersberg Mons Jovis after their god of thunder, Jupiter . According to other theories, the name of the mountain was derived from the Celtic dunum (meaning "mountain") or from the name of a Celtic deity, Taranis . During the Celtic La Tène period, around 150 BC, an important settlement ( oppidum )

4017-472: The Late Permian. Members of the modern orders Archostemata and Adephaga are known from the Late Permian. Complex wood boring traces found in the Late Permian of China suggest that members of Polyphaga , the most diverse group of modern beetles, were also present by the Late Permian. The terrestrial fossil record of the Permian is patchy and temporally discontinuous. Early Permian records are dominated by equatorial Europe and North America, while those of

4120-617: The Late Permian. By the Changhsingian, only a handful (4-6) genera remained. Corals exhibited a decline in diversity over the course of the Middle and Late Permian. Terrestrial life in the Permian included diverse plants, fungi , arthropods , and various types of tetrapods . The period saw a massive desert covering the interior of Pangaea . The warm zone spread in the northern hemisphere, where extensive dry desert appeared. The rocks formed at that time were stained red by iron oxides,

4223-623: The Lopingian in China. Modern amphibians ( lissamphibians ) are suggested to have originated during Permian, descending from a lineage of dissorophoid temnospondyls or lepospondyls . The diversity of fish during the Permian is relatively low compared to the following Triassic. The dominant group of bony fishes during the Permian were the " Paleopterygii " a paraphyletic grouping of Actinopterygii that lie outside of Neopterygii . The earliest unequivocal members of Neopterygii appear during

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4326-605: The Lopingian series. The GSSP for the base of the Wuchiapingian is located at Penglaitan, Guangxi , China and was ratified in 2004. The boundary is defined by the first appearance of Clarkina postbitteri postbitteri The Changhsingian was originally derived from the Changxing Limestone, a geological unit first named by the Grabau in 1923, ultimately deriving from Changxing County , Zhejiang .The GSSP for

4429-598: The Lopingian to a series, including all Permian deposits in South China that overlie the Maokou Limestone. In 1995, a vote by the Subcommission on Permian Stratigraphy of the ICS adopted the Lopingian as an international standard chronostratigraphic unit. The Wuchiapinginan and Changhsingian were first introduced in 1962, by J. Z. Sheng as the "Wuchiaping Formation" and "Changhsing Formation" within

4532-514: The Middle Permian. There were no flying vertebrates, though the extinct lizard-like reptile family Weigeltisauridae from the Late Permian had extendable wings like modern gliding lizards , and are the oldest known gliding vertebrates. Permian stem-amniotes consisted of lepospondyli and batrachosaurs , according to some phylogenies; according to others, stem-amniotes are represented only by diadectomorphs . Temnospondyls reached

4635-598: The Middle and Late Permian are dominated by temperate Karoo Supergroup sediments of South Africa and the Ural region of European Russia. Early Permian terrestrial faunas of North America and Europe were dominated by primitive pelycosaur synapsids including the herbivorous edaphosaurids , and carnivorous sphenacodontids , diadectids and amphibians . Early Permian reptiles, such as acleistorhinids , were mostly small insectivores. Synapsids (the group that would later include mammals) thrived and diversified greatly during

4738-514: The Ochoan, corresponding to the Lopingian. During the Permian, all the Earth 's major landmasses were collected into a single supercontinent known as Pangaea , with the microcontinental terranes of Cathaysia to the east. Pangaea straddled the equator and extended toward the poles, with a corresponding effect on ocean currents in the single great ocean (" Panthalassa ", the "universal sea"), and

4841-620: The Permian are based around the first appearance datum of specific species of conodont , an enigmatic group of jawless chordates with hard tooth-like oral elements. Conodonts are used as index fossils for most of the Palaeozoic and the Triassic. The Cisuralian Series is named after the strata exposed on the western slopes of the Ural Mountains in Russia and Kazakhstan. The name was proposed by J. B. Waterhouse in 1982 to comprise

4944-582: The Permian, representing up to a third of all insects at some localities. Mecoptera (sometimes known as scorpionflies) first appeared during the Early Permian, going on to become diverse during the Late Permian. Some Permian mecopterans, like Mesopsychidae have long proboscis that suggest they may have pollinated gymnosperms. The earliest known beetles appeared at the beginning of the Permian. Early beetles such as members of Permocupedidae were likely xylophagous , feeding on decaying wood. Several lineages such as Schizophoridae expanded into aquatic habitats by

5047-540: The Permian-Triassic boundary, corresponding to the eruption of the Siberian Traps , which released more than 5 teratonnes of CO 2 , more than doubling the atmospheric carbon dioxide concentration. A -2% δ O excursion signifies the extreme magnitude of this climatic shift. This extremely rapid interval of greenhouse gas release caused the Permian-Triassic mass extinction, as well as ushering in an extreme hothouse that persisted for several million years into

5150-508: The Permian. Xenacanthiformes , another extinct group of shark-like chondrichthyans, were common in freshwater habitats, and represented the apex predators of freshwater ecosystems. Four floristic provinces in the Permian are recognised, the Angaran , Euramerican, Gondwanan, and Cathaysian realms. The Carboniferous Rainforest Collapse would result in the replacement of lycopsid -dominated forests with tree-fern dominated ones during

5253-543: The Permian. The end of the Early Permian ( Cisuralian ) saw a major faunal turnover, with most lineages of primitive " pelycosaur " synapsids becoming extinct, being replaced by more advanced therapsids . The end of the Capitanian Stage of the Permian was marked by the major Capitanian mass extinction event , associated with the eruption of the Emeishan Traps . The Permian (along with the Paleozoic) ended with

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5356-524: The Permian. The extinct order Productida was the predominant group of Permian brachiopods, accounting for up to about half of all Permian brachiopod genera. Brachiopods also served as important ecosystem engineers in Permian reef complexes. Amongst ammonoids , Goniatitida were a major group during the Early-Mid Permian, but declined during the Late Permian. Members of the order Prolecanitida were less diverse. The Ceratitida originated from

5459-515: The Permian. This is likely due to competition by Hemiptera , due to their similar mouthparts and therefore ecology. Primitive relatives of damselflies and dragonflies ( Meganisoptera ), which include the largest flying insects of all time, also declined during the Permian. Holometabola , the largest group of modern insects, also diversified during this time. " Grylloblattidans ", an extinct group of winged insects thought to be related to modern ice crawlers , reached their apex of diversity during

5562-654: The Usolka section in the southern Urals, which was ratified in 2018. The GSSP is defined by the first appearance of Sweetognathus binodosus . The Artinskian was named after the city of Arti in Sverdlovsk Oblast , Russia. It was named by Karpinsky in 1874. The Artinskian currently lacks a defined GSSP. The proposed definition for the base of the Artinskian is the first appearance of Sweetognathus aff. S. whitei. The Kungurian takes its name after Kungur ,

5665-736: The Word Formation by Johan August Udden in 1916, Glenister and Furnish in 1961 was the first publication to use it as a chronostratigraphic term as a substage of the Guadalupian Stage. The GSSP for the base of the Wordian is located in Guadalupe Pass, Texas, within the sediments of the Getaway Limestone Member of the Cherry Canyon Formation , which was ratified in 2001. The base of the Wordian

5768-413: The Wuchiapingian, followed by a slight rise during the Changhsingian. The Permian was cool in comparison to most other geologic time periods, with modest pole to Equator temperature gradients. At the start of the Permian, the Earth was still in the Late Paleozoic icehouse (LPIA), which began in the latest Devonian and spanned the entire Carboniferous period, with its most intense phase occurring during

5871-506: The amount of lava estimated to have been produced during this period, the worst-case scenario is the release of enough carbon dioxide from the eruptions to raise world temperatures five degrees Celsius. Another hypothesis involves ocean venting of hydrogen sulfide gas. Portions of the deep ocean will periodically lose all of its dissolved oxygen allowing bacteria that live without oxygen to flourish and produce hydrogen sulfide gas. If enough hydrogen sulfide accumulates in an anoxic zone ,

5974-411: The ancestors of many present-day families. Rich forests were present in many areas, with a diverse mix of plant groups. The southern continent saw extensive seed fern forests of the Glossopteris flora. Oxygen levels were probably high there. The ginkgos and cycads also appeared during this period. Insects, which had first appeared and become abundant during the preceding Carboniferous, experienced

6077-405: The base of the Asselian is located in the Aidaralash River valley near Aqtöbe , Kazakhstan, which was ratified in 1996. The beginning of the stage is defined by the first appearance of Streptognathodus postfusus . The Sakmarian is named in reference to the Sakmara River in the southern Urals, and was coined by Alexander Karpinsky in 1874. The GSSP for the base of the Sakmarian is located at

6180-418: The base of the Capitanian is located at Nipple Hill in the southeast Guadalupe Mountains of Texas, and was ratified in 2001, the beginning of the stage is defined by the first appearance of Jinogondolella postserrata. The Lopingian was first introduced by Amadeus William Grabau in 1923 as the "Loping Series" after Leping , Jiangxi , China. Originally used as a lithostraphic unit, T.K. Huang in 1932 raised

6283-404: The base of the Changhsingian is located 88 cm above the base of the Changxing Limestone in the Meishan D section, Zhejiang, China and was ratified in 2005, the boundary is defined by the first appearance of Clarkina wangi. The GSSP for the base of the Triassic is located at the base of Bed 27c at the Meishan D section, and was ratified in 2001. The GSSP is defined by the first appearance of

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6386-412: The beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison , who named it after the region of Perm in Russia . The Permian witnessed the diversification of the two groups of amniotes , the synapsids and

6489-429: The chondrichthyan clade Holocephali , which contains living chimaeras , reached their apex of diversity during the Carboniferous-Permian, the most famous Permian representative being the "buzz-saw shark" Helicoprion , known for its unusual spiral shaped spiral tooth whorl in the lower jaw. Hybodonts , a group of shark-like chondrichthyans, were widespread and abundant members of marine and freshwater faunas throughout

6592-449: The climate became notably more arid at the end of the Carboniferous and beginning of the Permian. Nonetheless, temperatures continued to cool during most of the Asselian and Sakmarian, during which the LPIA peaked. By 287 million years ago, temperatures warmed and the South Pole ice cap retreated in what was known as the Artinskian Warming Event (AWE), though glaciers remained present in the uplands of eastern Australia, and perhaps also

6695-399: The conodont Hindeodus parvus . The Russian Tatarian Stage includes the Lopingian, Capitanian and part of the Wordian, while the underlying Kazanian includes the rest of the Wordian as well as the Roadian. In North America, the Permian is divided into the Wolfcampian (which includes the Nealian and the Lenoxian stages); the Leonardian (Hessian and Cathedralian stages); the Guadalupian; and

6798-434: The continental interior by the more advanced seed ferns and early conifers as a result of the Carboniferous rainforest collapse . At the close of the Permian, lycopod and equisete swamps reminiscent of Carboniferous flora survived only in Cathaysia , a series of equatorial islands in the Paleo-Tethys Ocean that later would become South China . The Permian saw the radiation of many important conifer groups, including

6901-458: The decline of early synapsid clades was apparently a slow event that lasted about 20 Ma, from the Sakmarian to the end of the Kungurian . Predator-prey interactions among terrestrial synapsids became more dynamic. If terrestrial deposition ended around the end of the Cisuralian in North America and began in Russia during the early Guadalupian, a continuous record of the transition is not preserved. Uncertain dating has led to suggestions that there

7004-439: The dinocephalian Estemmenosuchus has been described as showing that the skin was glandular and lacked both scales and hair. Coprolites containing what appear to be hairs have been found from the Late Permian . Though the source of these hairs is not known with certainty, they may suggest that hair was present in at least some Permian therapsids. The closure of the pineal foramen in probainognathian cynodonts may indicate

7107-419: The distinctive Burnetiamorpha , but support for the monophyly of Biarmosuchia is relatively low. Many biarmosuchians are known for extensive cranial ornamentation. Dinocephalia comprises two distinctive groups, the Anteosauria and Tapinocephalia . Historically, carnivorous dinocephalians, including both anteosaurs and titanosuchids, were called titanosuchians and classified as members of Theriodontia, while

7210-412: The diverse Dinocephalia . Dinocephalians become extinct at the end of the Middle Permian, during the Capitanian mass extinction event . Late Permian faunas are dominated by advanced therapsids such as the predatory sabertoothed gorgonopsians and herbivorous beaked dicynodonts , alongside large herbivorous pareiasaur parareptiles . The Archosauromorpha , the group of reptiles that would give rise to

7313-401: The earliest Permian of France. The oldest known fossils definitively assignable to modern cycads are known from the Late Permian. In Cathaysia, where a wet tropical frost-free climate prevailed, the Noeggerathiales , an extinct group of tree fern-like progymnosperms were a common component of the flora The earliest Permian (~ 298 million years ago) Cathyasian Wuda Tuff flora, representing

7416-573: The early Wuchiapingian, following the emplacement of the Emeishan Traps, global temperatures declined as carbon dioxide was weathered out of the atmosphere by the large igneous province's emplaced basalts. The late Wuchiapingian saw the finale of the Late Palaeozoic Ice Age, when the last Australian glaciers melted. The end of the Permian is marked by a temperature excursion, much larger than the Emeishan Thermal Excursion, at

7519-431: The end of the Permian. Nautiloids , a subclass of cephalopods, surprisingly survived this occurrence. There is evidence that magma , in the form of flood basalt , poured onto the Earth's surface in what is now called the Siberian Traps , for thousands of years, contributing to the environmental stress that led to mass extinction. The reduced coastal habitat and highly increased aridity probably also contributed. Based on

7622-438: The eucynodonts remained. The therocephalians , relatives of the cynodonts, managed to survive the Permian–Triassic extinction and continued to diversify through the Early Triassic period. Approaching the end of the period, however, the therocephalians were in decline to eventual extinction, likely outcompeted by the rapidly diversifying Saurian lineage of diapsids , equipped with sophisticated respiratory systems better suited to

7725-580: The family Daraelitidae within Prolecanitida during the mid-Permian, and extensively diversified during the Late Permian. Only three families of trilobite are known from the Permian, Proetidae , Brachymetopidae and Phillipsiidae . Diversity, origination and extinction rates during the Early Permian were low. Trilobites underwent a diversification during the Kungurian-Wordian, the last in their evolutionary history, before declining during

7828-471: The first of the cynodonts . Like all land animals, the therapsids were seriously affected by the Permian–Triassic extinction event , with the very successful gorgonopsians and the biarmosuchians dying out altogether and the remaining groups— dicynodonts , therocephalians and cynodonts —reduced to a handful of species each by the earliest Triassic . Surviving dicynodonts were represented by two families of disaster taxa ( Lystrosauridae and Myosauridae ),

7931-429: The gas can rise into the atmosphere. Oxidizing gases in the atmosphere would destroy the toxic gas, but the hydrogen sulfide would soon consume all of the atmospheric gas available. Hydrogen sulfide levels might have increased dramatically over a few hundred years. Models of such an event indicate that the gas would destroy ozone in the upper atmosphere allowing ultraviolet radiation to kill off species that had survived

8034-631: The herbivorous Tapinocephalidae were classified as members of Anomodontia. Anomodontia includes the dicynodonts , a clade of tusked, beaked herbivores, and the most diverse and long-lived clade of non-cynodont therapsids. Other members of Anomodontia include Suminia , which is thought to have been a climbing form. Gorgonopsia is an abundant but morphologically homogeneous group of saber-toothed predators . It has been suggested that Therocephalia might not be monophyletic, with some species more closely related to cynodonts than others. However, most studies regard Therocephalia as monophyletic. Cynodonts are

8137-721: The introduction of the term Permian , rocks of equivalent age in Germany had been named the Rotliegend and Zechstein , and in Great Britain as the New Red Sandstone . The term Permian was introduced into geology in 1841 by Sir Roderick Impey Murchison , president of the Geological Society of London , after extensive Russian explorations undertaken with Édouard de Verneuil in the vicinity of

8240-748: The late Carboniferous in Euramerica, and result in the differentiation of the Cathaysian floras from those of Euramerica. The Gondwanan floristic region was dominated by Glossopteridales , a group of woody gymnosperm plants, for most of the Permian, extending to high southern latitudes. The ecology of the most prominent glossopterid, Glossopteris , has been compared to that of bald cypress , living in mires with waterlogged soils. The tree-like calamites , distant relatives of modern horsetails , lived in coal swamps and grew in bamboo -like vertical thickets. A mostly complete specimen of Arthropitys from

8343-664: The latter part of the Pennsylvanian epoch. A significant trend of increasing aridification can be observed over the course of the Cisuralian. Early Permian aridification was most notable in Pangaean localities at near-equatorial latitudes. Sea levels also rose notably in the Early Permian as the LPIA slowly waned. At the Carboniferous-Permian boundary, a warming event occurred. In addition to becoming warmer,

8446-564: The lower sprawling posture of many reptiles and amphibians . Therapsids evolved from earlier synapsids commonly called " pelycosaurs ", specifically within the Sphenacodontia , more than 279.5 million years ago. They replaced the pelycosaurs as the dominant large land animals in the Guadalupian through to the Early Triassic. In the aftermath of the Permian–Triassic extinction event , therapsids declined in relative importance to

8549-432: The mammaliaform Morganucodon suggest that even early mammaliaforms had reptile-like metabolic rates. Evidence for respiratory turbinates, which have been hypothesized to be indicative of endothermy, was reported in the therocephalian Glanosuchus , but subsequent study showed that the apparent attachment sites for turbinates may simply be the result of distortion of the skull. The evolution of integument in therapsids

8652-455: The most extensive extinction event recorded in paleontology : the Permian–Triassic extinction event . 90 to 95% of marine species became extinct , as well as 70% of all land organisms. It is also the only known mass extinction of insects. Recovery from the Permian–Triassic extinction event was protracted; on land, ecosystems took 30 million years to recover. Trilobites , which had thrived since Cambrian times, finally became extinct before

8755-473: The most potent greenhouse gases ) into the atmosphere to raise world temperatures an additional five degrees Celsius. The frozen methane hypothesis helps explain the increase in carbon-12 levels found midway in the Permian–Triassic boundary layer. It also helps explain why the first phase of the layer's extinctions was land-based, the second was marine-based (and starting right after the increase in C-12 levels), and

8858-414: The mountainous regions of far northern Siberia. Southern Africa also retained glaciers during the late Cisuralian in upland environments. The AWE also witnessed aridification of a particularly great magnitude. In the late Kungurian, cooling resumed, resulting in a cool glacial interval that lasted into the early Capitanian, though average temperatures were still much higher than during the beginning of

8961-713: The next geologic epoch, the Triassic. The Permian climate was also extremely seasonal and characterised by megamonsoons , which produced high aridity and extreme seasonality in Pangaea's interiors. Precipitation along the western margins of the Palaeo-Tethys Ocean was very high. Evidence for the megamonsoon includes the presence of megamonsoonal rainforests in the Qiangtang Basin of Tibet, enormous seasonal variation in sedimentation, bioturbation, and ichnofossil deposition recorded in sedimentary facies in

9064-519: The other four clades are controversial. The most widely accepted hypothesis of therapsid relationships, the Hopson and Barghausen paradigm, was first proposed in 1986. Under this hypothesis, biarmosuchians are the earliest-diverging major therapsid group, with the other five groups forming the Eutherapsida, and within Eutherapsida, gorgonopsians are the sister taxon of eutheriodonts, together forming

9167-461: The pineal foramen, and the foramen is completely absent in probainognathian cynodonts. Evidence from oxygen isotopes, which are correlated with body temperature, suggests that most Permian therapsids were ectotherms and that endothermy evolved convergently in dicynodonts and cynodonts near the end of the Permian. In contrast, evidence from histology suggests that endothermy is shared across Therapsida, whereas estimates of blood flow rate and lifespan in

9270-507: The presence of foramina on the snout of therocephalians and early cynodonts, but the arrangement of foramina in these taxa actually closely resembles lizards, which would make the presence of mammal-like whiskers unlikely. Therapsids evolved from a group of pelycosaurs called sphenacodonts . Therapsids became the dominant land animals in the Middle Permian , displacing the pelycosaurs. Therapsida consists of four major clades :

9373-596: The rapidly diversifying archosaurian sauropsids ( pseudosuchians , dinosaurs and pterosaurs , etc.) during the Middle Triassic. The therapsids include the cynodonts , the group that gave rise to mammals ( Mammaliaformes ) in the Late Triassic around 225 million years ago, the only therapsid clade that survived beyond the end of the Triassic . The only other group of therapsids to have survived into

9476-439: The result of intense heating by the sun of a surface devoid of vegetation cover. A number of older types of plants and animals died out or became marginal elements. The Permian began with the Carboniferous flora still flourishing. About the middle of the Permian a major transition in vegetation began. The swamp -loving lycopod trees of the Carboniferous, such as Lepidodendron and Sigillaria , were progressively replaced in

9579-587: The same area hundreds of years prior, and which is now located in the Perm Krai administrative region. Between 1853 and 1867, Jules Marcou recognised Permian strata in a large area of North America from the Mississippi River to the Colorado River and proposed the name Dyassic , from Dyas and Trias , though Murchison rejected this in 1871. The Permian system was controversial for over

9682-473: The scarcely known Kombuisia , and a single group of large stocky herbivores , the Kannemeyeriiformes , which were the only dicynodont lineage to thrive during the Triassic. They and the medium-sized cynodonts (including both carnivorous and herbivorous forms) flourished worldwide throughout the Early and Middle Triassic. They disappear from the fossil record across much of Pangea at the end of

9785-440: The sister taxon of Eutheriodontia, other studies have found dinocephalians and anomodonts to form a clade, and both the phylogenetic position and monophyly of Biarmosuchia remain controversial. In addition to the six major groups, there are several other lineages and species of uncertain classification. Raranimus from the early Middle Permian of China is likely to be the earliest-diverging known therapsid. Tetraceratops from

9888-408: The southeastern South China. The Central Pangean Mountains , which began forming due to the collision of Laurasia and Gondwana during the Carboniferous, reached their maximum height during the early Permian around 295 million years ago, comparable to the present Himalayas , but became heavily eroded as the Permian progressed. The Kazakhstania block collided with Baltica during the Cisuralian, while

9991-421: The sprawling legs of reptiles and pelycosaurs. Also compared to these groups, the feet were more symmetrical, with the first and last toes short and the middle toes long, an indication that the foot's axis was placed parallel to that of the animal, not sprawling out sideways. This orientation would have given a more mammal -like gait than the lizard -like gait of the pelycosaurs. The physiology of therapsids

10094-532: The spread of conifers and their increasing prevalence throughout terrestrial ecosystems. Bennettitales , which would go on to become in widespread the Mesozoic, first appeared during the Cisuralian in China. Lyginopterids , which had declined in the late Pennsylvanian and subsequently have a patchy fossil record, survived into the Late Permian in Cathaysia and equatorial east Gondwana. The Permian ended with

10197-423: The third land-based again. Therapsids Therapsida is a clade comprising a major group of eupelycosaurian synapsids that includes mammals and their ancestors and close relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, resulting in a more "standing" quadrupedal posture, as opposed to

10300-413: The toxic gas. There are species that can metabolize hydrogen sulfide. Another hypothesis builds on the flood basalt eruption theory. An increase in temperature of five degrees Celsius would not be enough to explain the death of 95% of life. But such warming could slowly raise ocean temperatures until frozen methane reservoirs below the ocean floor near coastlines melted, expelling enough methane (among

10403-581: The very hot, dry and oxygen-poor world of the End-Triassic. Dicynodonts were among the most successful groups of therapsids during the Late Permian, and survived through to near the end of the Triassic. Mammals are the only living therapsids. The mammalian crown group , which evolved in the Early Jurassic period, radiated from a group of mammaliaforms that included the docodonts . The mammaliaforms themselves evolved from probainognathians ,

10506-474: Was built on the Donnersberg, covering some 240 hectares. Part of the wall ( Keltenwall ) surrounding this settlement has been reconstructed. Archeological excavations are ongoing. In the Middle Ages , five castles surrounded the strategically placed mountain: Tannenfels , Wildenstein , Hohenfels , Falkenstein and Ruppertsecken . Today, only ruins remain of these five castles. About 900 metres east of

10609-667: Was named in 1968 in reference to the Road Canyon Member of the Word Formation in Texas. The GSSP for the base of the Roadian is located 42.7m above the base of the Cutoff Formation in Stratotype Canyon, Guadalupe Mountains, Texas, and was ratified in 2001. The beginning of the stage is defined by the first appearance of Jinogondolella nankingensis . The Wordian was named in reference to

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