Permian period began 300 million years ago and ended 250 million years ago, the Permian period is the final period of the Paleozoic era. During this period, the Earth was divided into vast areas of land and ocean. Most of the continents of that time, with the exception of Asia, were fused together to form the giant supercontinent known today as Pangea. This huge piece of land stretched from south pole to the North Pole. Pangea was surrounded by a giant ocean known as Panthalassa. To the east of Pangea was the continent of Asia, and between Pangea and Asia there was a sea called Paleo-Tethys. East of Pangea and south of Asia was the Tethys Sea.

The weather changed greatly during this period. At the beginning of this period, there were glaciers on the Earth that formed during the Carboniferous. However, by the middle of the Permian, the climate became warmer. Rising temperatures caused glaciers to melt, and small water areas on the continents dried up. This drying continued throughout this period until the climate changed to a colder one.

Life during this period was diverse and continued to evolve. Some plants and animals that lived in the Carboniferous continued to flourish in the Permian period. Also, thanks to mutations, new species of life appeared and just began to take over the land. Molluscs, brachiopods, ammonoids, fusulinids and echinoderms lived in the seas and oceans during this period. Thermal life that existed during this phylum includes a variety of tetrapods, vascular and nonvascular plants, arthropods, and fungi. During this time, groups of coniferous plants appeared on the scene of life, as well as some cicadas and ginkgo plants.

Insects also began to evolve during the Permian period, with cockroaches appearing in particular. Primitive cockroaches began to evolve at the end Carboniferous period highly successful. They had four folding wings; well-developed eyes, six legs, a system of olfactory antennas, an exoskeleton. They could absorb both plant and animal food. Scientists estimate that these primitive cockroaches made up about 90% of all insect species at that time. The other 10% of insects that existed at that time were beetles known as Coleoptera, true beetles known as Hemiptera and dragonflies known as Odonata.

Diadectians, amphibians and pelisosaurs also lived during this period. Around the middle of this period, the first primitive therapsids evolved, including dinocephaly. Towards the end of the period, these primitive therapsids became more advanced and eventually gave rise to animals such as gorgonopans and dicynodonts. At this time, archosaurs also began their evolution. Early mammal relatives known as synapsids also flourished during this period.

However, not all species were able to survive the Permian period. By the end of this period, trilobites and many tree species such as Sigillaria and Lepidodendron became extinct. Their niche was occupied by conifers and seed ferns. This period would end tragically with the great Permian–Triassic extinction event (also known as the Great Dying). Scientists believe that this event killed approximately 90-95% of all marine species and about 70-75% terrestrial species animals. Scientists aren't entirely sure what caused this mass extinction

However, the end of the Permian period witnessed the most severe mass extinction event in Earth's history.

Climate and geography

As in the previous Carboniferous period, the climate of the Permian period was closely related to its. Most of The planet's land mass remained locked into the supercontinent Pangea, with outlying branches that include modern-day Siberia, Australia and China. At the beginning of the Permian period, much of southern Pangea was covered by glaciers, but global temperatures increased significantly by the beginning of the Triassic period. the world has become drier, stimulating the evolution of new reptile species better adapted to climate change.

Animal world:

Reptiles

Dimetrodon

The most important event of the Permian period was the appearance of "synapsid" reptiles (animals that developed holes in their skulls behind each eye). During the Early Permian, these synapsids resembled crocodiles and even dinosaurs, including Varanops and Dimetrodon.

By the end of the Permian period, the synapsids had split from the therapsids or "mammal-reptiles"; at the same time, the first archosaurs appeared, "diapsid" reptiles characterized by two openings in the skull behind each eye. A quarter of a billion years ago, no one could have predicted that these archosaurs were destined to evolve into the very first dinosaurs of the Mesozoic era!

Amphibians

Diplocaulus

The increasingly drier conditions of the Permian period did not encourage significant development, unlike more adaptable reptiles (which could lay eggs on land, while amphibians were forced to live near bodies of water). Two of the most notable amphibians of the early Permian were the 2-meter-tall Eriotes and the strange Diplocaulus.

Insects

The Permian period had not yet seen the changes in insect forms observed during the following Mesozoic era. The most common insects were giant cockroaches (their tough exoskeletons gave them a selective advantage over other terrestrials), as well as various species of dragonflies, which were not as impressive as their early Carboniferous ancestors (for example, Meganeura).

Sea life

Helicoprion

The Permian period produced surprisingly few marine fossils; the most reliable genera are prehistoric sharks, such as Helicoprion And Xenacanthus And prehistoric fish, such as Acanthodes. (This does not mean that there were few sharks and fish in the world's oceans, but rather that geological conditions did not lend themselves to the process of fossilization.) The diversity of marine reptiles was extremely poor, especially in comparison with the subsequent Triassic period; one of the few identified examples is the mysterious Claudiosaurus.

Vegetable world

Unless you're a paleobotanist, you might not be interested in swapping one weird prehistoric lycopod plant for another, Glossopteris.

Suffice it to say that the Permian period witnessed the evolution of new species of seed plants, as well as the spread of ferns, conifers and cicadas (which were an important food source for Mesozoic era reptiles).

Permian mass extinction

Everyone knows about the K-T extinction (Cretaceous-Paleogene extinction) that wiped out the dinosaurs about 66 million years ago, but the most severe was the Permian, which wiped out about 70% of terrestrial genera and a whopping 95% of marine genera. No one knows for sure what caused this extinction, although most probable cause is a series of massive volcanic eruptions. It was this “great disappearance” at the end of the Permian that opened ecological niches for new species of terrestrial and marine reptiles and led, in turn, to the possible evolution of dinosaurs.

If you find an error, please highlight a piece of text and click Ctrl+Enter.

Permian geological period, Carboniferous (285 - 250.0 million years ago) - last period Paleozoic. The Permian period is divided into two sections: lower and upper.

The climate of the Permian period was characterized by pronounced zonality and increasing aridity. In general, we can say that it was close to the modern one. If anything, he had more similarities with modern climate than in subsequent periods of the Mesozoic. At the beginning of the Permian, bacteria and fungi finally learned to utilize wood, and the oxygen catastrophe of the Carboniferous period receded without breaking out properly. Main stream evolutionary process in the Permian period - the development of increasingly arid regions by plants and animals, while evolution proceeded very quickly and in many parallel directions. The beginning of the Permian period was marked by glaciation on southern continents and, accordingly, lowering sea levels throughout the planet. In the middle of the Permian period this glaciation gave way to global warming. Glacial sedimentary rocks have been found in South America, South Africa, Antarctica and Australia. As Gondwana moved northward, the land warmed up and the ice gradually melted. At the same time, parts of Laurasia became very hot and dry, and vast deserts spread there. Mountain-building processes formed the Ural-Tien Shan platform, Atlantia connected with Asia, forming northern continent Laurasia. The American Cordillera and Andes, the Australian Cordillera and the Donetsk Ridge continue to form. In Gondwana, depressions formed with the accumulation of sedimentary rocks: sands, gypsum, conglomerates.

The climate is dry, inland seas, lakes, and swamps are disappearing. Differentiation climatic conditions determined high mountains. As a result of volcanoes, strata of volcanic rocks emerged.

The flora is characterized by a decrease in the number of sigillaria, lepidodendrons and cordaites, the appearance of ferns and new groups of gymnosperms. Calamites, tree and herbaceous ferns grow in swamps and bays.

Conifers, ginkgos and cycads are widespread. Cycads resemble palm trees, the reproductive organs of cycads are male and female cones, with small seeds.

On the Gondwana continent, which stretched across from Brazil Atlantic Ocean, included America and through Madagascar reached India and Australia, there are strata of red and yellow sandstones with remains marine fauna: sponges, bivalves, cephalopods, gastropods, brachiopods, echinoderms, but marine animal world The Permian period is poorer than the Carboniferous.

Foraminifera are rare, the number of sponges, corals, and echinoderms is decreasing, trilobites are absent, tabulates and ancient urchins are dying out.

Cephalopods developed new forms of ammonites, acquiring a complex organization, nautiloids appeared, forms of brachiopods appeared, living in Indian Ocean. Found in fresh and brackish waters bivalves. Among gastropods Prosobranchs have evolved, bryozoans exist, and reefs have formed. Ostracods and worm-like crustaceans develop.

The Permian mass extinction (informally referred to as The Great Dying, or The Greatest Mass Extinction of All Time) is one of the five mass extinctions. It marks the boundary between the Permian and Triassic geological periods (it also separates the Paleozoic and Mesozoic era). The age of this boundary according to the modern (2012) geochronological scale is 252.2 ± 0.5 million years.

Is one of major disasters biosphere in the history of the Earth, which led to the extinction of 96% of all marine species and 70% of terrestrial vertebrate species. The disaster was the only known mass extinction of insects, resulting in the extinction of about 57% of genera and 83% of species of the entire class of insects. Due to the loss of such quantity and diversity biological species restoration of the biosphere took much more a long period time compared to other disasters leading to extinctions. The models by which the extinction occurred are under debate. Various scientific schools suggest one to three extinction shocks. According to researchers from the Massachusetts Institute of Technology, 96% aquatic species and 70% of terrestrial species became extinct in just 60 thousand years.

Currently, experts do not have a generally accepted opinion about the causes of extinction. A number of possible reasons:

• · catastrophic events:
  • o increased volcanic activity in Siberia;
  • o the fall of one or many meteorites, or the collision of the Earth with an asteroid with a diameter of several tens of kilometers (one of the proofs of this hypothesis is the possible presence of a 500-kilometer crater in the area of ​​Wilkes Land);
  • o sudden release of methane from the seabed;
  • o acquisition by archaea (genus Methanosarcina) of the ability to process organic matter with the release of large volumes of methane.
• Gradual environmental changes:
• o anoxia -- changes chemical composition sea ​​water and atmosphere, in particular, oxygen deficiency;
• o increasing climate aridity;
• o change ocean currents and/or sea level under the influence of climate change.

The most common hypothesis is that the cause of the catastrophe was the outpouring of traps (first the relatively small Emeishan traps about 260 million years ago, then the colossal Siberian traps 251 million years ago), which could lead to a volcanic winter, Greenhouse effect due to the release of volcanic gases and others climate change that influenced the biosphere[

On the territory of the former Perm province. Now this tectonic structure is called the Cis-Ural Foredeep. Murchison also discovered its widespread distribution in the Urals and the Russian Plain.

This is the only geological system that has received a Russian name.

Permian divisions (systems)

system	Department	tier	Age, million years ago
Triassic	Lower	Indus	less
Permian	Lopinsky	Changsinsky	254,14-251,9
		Vuchapinsky	259,1-254,14
	Guadalupe	Keptensky	265,1-259,1
		Wordsky	268,8-265,1
		Rhodes	272,95-268,8
	Priuralsky	Kungursky	283,5-272,95
		Artinsky	290,1-283,5
		Sakmara	295,0-290,1
		Asselian	298,9-295,0
Carbon	Upper	Gzhelsky	more
Divisions are given according to IUGS as of December 2016

In accordance with the general stratigraphic scale adopted at a conference in Kazan in 2004, Russian geologists distinguish in the Permian system three departments: lower (Ural), middle (Biarmian) and upper (Tatar). The lower (Ural) section included the following stages (from bottom to top): Asselian, Sakmara, Artinskian, Kungurskian, Ufa. The middle (Biarmian) section included the Kazan and Urzhum stages, and the upper (Tatar) section included the Severodvinsk and Vyatka stages. It is also proposed to distinguish between the Urzhum and Severodvinsk stages a separate Yurpalovsky stage and a Vyaznikovsky stage above the Vyatka stage.

Flora and fauna of the Permian period

Insects

Of the insects in the Permian, there were beetles, which first appeared in this period - 270 million years ago (all or almost all belonged to the suborder Archostemata) and lacewings (all species passed into the Triassic). Caddis flies and scorpion flies appear. In the late Permian there were 11 families of the latter, but only 4 passed into the Triassic. single family caddis flies.

Climate

The climate of the Permian period was characterized by pronounced zonality and increasing aridity. In general, we can say that it was close to the modern one. If anything, it had more similarities to modern climates than the Mesozoic periods that followed.

In the Permian period, a belt of humid tropical climate, within which there was a vast ocean - Tethys. To the north of it there was a belt of hot and dry climate, which corresponds to the widespread development of salt-bearing and red-colored deposits. Located even further north temperate zone significant humidity with intense carbon accumulation. The southern temperate zone is fixed by the carbon-bearing deposits of Gondwana.

At the beginning of the period, glaciation continued, beginning in the Carboniferous. It was developed on the southern continents.

The Permian is characterized by red-colored continental sediments and deposits of salt-bearing lagoons, which reflects the increased aridity of the climate: the Permian is characterized by the most vast deserts in the history of the planet: sands even covered the territory of Siberia.

Paleogeography and tectonics

Permian deposits in Russia

One of the most famous fossil sites of the Permian period is Checkarda. In this pre-Ural location on the left bank of the Sylva River, deposits of the Koshelev Formation, dating to the Upper Permian, were exposed.

Another location of the Permian fauna is the unique Kotelnichskoye in the area of ​​​​the cities of Kotelnich and Sovetsk, Kirov region.

In addition, many Permian fossils have been found in the Arkhangelsk region, especially near the Malaya Northern Dvina and Mezen rivers. Among the animals found there, such famous ones as Scutosaurus, Inostracevia, and early cynodont were found

Permian period (Permian)

Permian period (Permian)

Page 7 of 7

Permian period refers to six periods Paleozoic era, through which this era ends. Permian begins 298 million years ago, lasts 47 million years and ends 252 million years before our time. This is the only period that received the Russian name in honor of the fact that it was first identified in Russia, in the region of the city of Perm. It is significant because it was during of this period The supercontinent Pangea was finally formed, which at the end of the period caused the most massive extinction of ancient plants and animals in history.

Main subsections of the Permian period, its geography and climate

In our country, the Permian period is usually divided into two sections - upper and lower, but in accordance with the division International Union geological sciences, the Permian period has three divisions- Loginsky (subdivided into the Changxinsky and Vuchalinsky stages), middle Guadalupean (Keltensky, Wordsky, Rhodesian stages) and Priuralsky (Kungursky, Artinsky, Sakmara and Asselian stages).

Permian period (Permian)	Departments	tiers
	Loginsky	Changxinsky
		Vuchalinsky
	Guadalupe	Keltensky
		Wordsky
		Rhodes
	Priuralsky	Kungursky
		Artinsky
		Sakmara
		Asselian

Throughout the Permian period, the geographical outlines of the Earth's continents were constantly changing. Laurasia gradually merged with Gondwana, resulting in the growth of Ural ridge. The Indian continent collided with the Asian part of the future Pangea, which sent the Himalayas skyward. In the North American segment, Appalachia grows. The outlines of coastal continental lines, as well as inland lakes and seas, are constantly changing, and all this occurs against the backdrop of constant volcanic activity and the eruption of magmatic hot rocks, which received the greatest activity towards the end of the Permian period, which, apparently, contributed to the extinction large groups plants and animals. If by the beginning of the Permian the carbon dioxide content in the atmosphere, which had already increased compared to the Carboniferous period, was 250 ppm, then by the middle it reached 1000 ppm, and by the end it rose to 3000 ppm.

Permian climate changed just as dramatically. The glaciation that began at the end of the Carboniferous period in the Permian period did not last long. The sea regressed due to the beginning of land uplift, caused by the convergence of continents. Over most of Pangea, huge sandy deserts, near the equator the climate acquired characteristics of a subtropical one, where precipitation was more frequent.

Sedimentation

During the Permian period, the vast majority of the Earth's salt-bearing basins were formed. These deposits were mainly formed in salt-bearing lagoons, since most of the future global continent was covered with sand, even Siberia was no exception. In some areas, sand deposits alternated with temporarily advancing and retreating coal layers.

Animals of the Permian period

At the beginning of the Permian period organic world was in many ways similar to coal and acquired individuality only closer to the middle. Invertebrate foraminifera (mainly schwagerinae), castle brachiopods (productids, spiriferids) still continued to exist in the seas; goniatids began to gradually die out, being replaced by ceratites. Brachiopods have new competitors - bivalves, distant ancestors of modern mussels. They fed well on bottom sediments, burrowing into the mud with the help of their powerful legs. Some have even mastered movement in the water column. By opening and sharply slamming the doors, they could swim short distances, which was enough to find new places of food.

At the beginning of the Permian, all coastal and swampy areas were inhabited animals of the Permian period, represented by many various types amphibians. Especially many of them were found in Siberian river basin Northern Dvina back in 1985 by Professor Amanitsky V.P. But little by little, stegocephals and their other varieties began to die out. In most cases, this is due to the appearance of new spiral-shaped predators in the aquatic environment - ammonites, relatives of nautiloids. Possessing powerful jaws, they easily dealt with defenseless and peace-loving amphibians, and they could not hide from them, either by burying themselves in the mud (one way or another they had to crawl onto land in search of food) or crawling out, since sooner or later they had to return to aquatic environment.

But this happened less and less often. Some amphibians of the Permian period as a result of evolution, they acquired powerful shells, but often this did not save them. Some species of amphibians preferred to spend more and more time on land rather than descend into dangerous seas. coastal waters, which is why some of them evolved into reptiles. Their eggs acquired their own shells, turning into eggs, which gave them the opportunity to say goodbye to the aquatic environment forever, because now they did not have to return to it even for reproduction.

The first reptiles were creatures that looked more like small lizards. They ate mainly various beetles, including large quantities appeared in the Permian period, all kinds of lacewings and caddis flies. But over time, huge reptiles developed from them, with powerful developed jaws, like today's crocodiles. Ancient reptiles were very clumsy, since their legs were located on the sides of their bodies, which is why they moved as if waddling, and could not develop mobility and speed. But evolution corrected this too. Over time, a branch of gorgonopsians developed among reptiles, whose legs were located directly under the body, which greatly increased their mobility. The jaws of many gorgonopsians were equipped sharp teeth, which made them formidable predators, capable of hunting other even armored, low-moving reptiles.

During the Permian period it became extinct great amount ancient ray-finned fish, a variety of sharks and lobe-finned fish also disappeared. And some species of reptiles, on the contrary, returned to the aquatic environment, only now they were no longer those ancient, barely mobile amphibians, but formidable predators like mesosaurs, for whom it was not difficult to tear apart such, in their time, invincible opponents as sharks. They mainly fed on small invertebrates and fish, but were not averse to eating large prey.

In some parts of the continents, some species of animal-like reptiles appeared by the end of the Carboniferous period. In the Permian period they developed into huge herbivorous reptiles, the most major representatives fauna of the Permian period. This gigantism was associated with the fact that the long-digesting plant food demanded to grow giant stomachs for its processing, and evolutionary development provided these stomachs with means of movement and eating. As a result, ever larger varieties of amphibians were born. At first, carnivorous predatory varieties of reptiles were much smaller in size, but evolution made its own adjustments here, as a result of which predators by the end of the Permian were not inferior, and sometimes even surpassed their carnivorous counterparts in size.

The convergence of the continents caused drought to come to vast areas of land. The changing climate pushed evolution to create more and more new species, which, without surviving, died out for 5-10 million years. Due to sharp changes in day and night temperatures, many amphibians acquired huge ridges on their backs, with the help of which they generated heat. And at night, living creatures were forced to hide in caves and crevices, where the daytime warmth was somehow preserved.

Everything pushed evolution towards the creation of warm-blooded animals. And towards the end of the Permian period, their first species appeared. They were more viable. They did not need to warm up for a long time in the morning sun, and therefore they were much more active. In order to generate heat through metabolism, these reptiles have developed a completely new digestive process. Food began to be digested many times faster. Many warm-blooded animals, for example - cynodonts(Fig. 1), acquired jaws equipped with teeth of various orientations, like modern mammals. The incisors could be used to grab and bite off food, the fangs were good for tearing food into pieces, and the flat molars were great for more thorough chewing.

Rice. 1 - Skeleton of a Permian cynodont

The skulls of these reptiles acquired new forms, from which it could be judged that their heads acquired strong jaw muscles for chewing food. The nostrils were separated from the throat by the palate, like those of modern crocodiles, which gave them the ability to breathe even with their mouth closed. Many were covered with wool for thermoregulation.

Due to their adaptability, these animal reptiles survived the subsequent dinosaurs and two periods of general extinction. Subsequently, it was they who became the ancestors of mammals that dominate throughout the world to this day.

The terrestrial flora began to change significantly only by the middle of the Permian period. And by the late Permian it acquires a more uniform appearance, which is no longer characteristic of the Paleozoic, since most plant species became gymnosperms. But this process of evolution did not progress with equal direction everywhere. In parts of the future European continent, these modifications began only with the onset of the Triassic, and in the vast territories of Gondwana even later.

Much different from carbon ones big amount sigillaria, cordaites and lepidodendrons. In the first half of the Permian, the main predominant species were ferns and gymnosperms, although calamites were also preserved in swampy and humid warm areas, although there they were increasingly crowded out various types herbaceous and tree ferns.

All more territories capture conifers, ginkgo and cycad, more reminiscent of modern palm trees. But these plants, like conifers, reproduce with the help of cones, of which there are two types - female and male. The seeds of these plants are relatively small in size.

Rice. 2 - Plants of the Permian period

Nowadays, only one species of ginkgo remains. And ginkgo survived only thanks to people. The ancient Chinese and Japanese took this tree with wide, lobed wings as sacred and planted it around temples, thanks to which the plant has survived to this day and is found in almost all botanical gardens.

Also in the Permian period, tongue ferns were extremely common. They were a bunch of roots attached to the soil, from which grew a rough branching trunk with fern-like leaves. Among these varieties there were both tree and shrub forms. On sections of many tongue ferns, rings are visible that arose through seasonal climatic changes.

Coniferous abundance was generally similar to modern Araucarias. There were also cordaites similar to modern ones, similar to modern pines and growing in large numbers on the islands of New Zealand. It was they who formed the main strata of coal in the Permian period.

Herbaceous and flowering plants. In some areas of the Earth during the Permian period, due to the riot of vegetation and the dominance of calcareous shells of animals, absorbing carbon dioxide and releasing oxygen, an atmosphere much similar to ours today reigned. And if it were not for the volcanic and mining activity that accompanies the convergence and collision of continental masses with each other, the process of earthly evolution could have gone differently in many ways.

Mass extinction of species at the end of the Permian period

In general, there is no consensus among scientists about the reasons for this mass extinction species at the end of the Permian period. Some say that the impetus for this was a giant meteorite that fell on the surface of the planet, others blame it all on the volcanic activity that accompanied the merging of the ancient continents into one giant one - Pangea. In both cases, huge masses of all kinds of pollutants were raised into the atmosphere, long years which blocked both plants and animals from access to the sun, as a result of which up to 90% of all species became extinct due to a kind of post-steroidal or volcanic winter on the Permian-Triassic border marine organisms and up to 70% terrestrial. In particular, four-rayed corals and tabulates disappeared from the Earth forever, fusulenids, most Paleozoic goanite brachiopods and straight-shelled nautiloids ceased to exist. Trilobites, the ancient sea ​​urchins, ancient lilies, many Paleozoic fish and other vertebrates. Most spore plants also disappeared from the face of the earth.

Minerals of the Permian period

During the Permian period, coal deposits continued to form, although with less efficiency. This period accounts for a quarter of all the world's anthracite reserves (the Pechera and Taimyr basins, the upper Minusinsk, Kuznetsk and Tunguska Russian coal horizons). Also, some oil horizons are Permian in age (Volga-Ural province, many fields in the United States). The Permian period was also marked by gas fields (Hugoton (USA, Kansas), Iranian fields).