The Permian period is the last in the Paleozoic era. It began 290,000,000 years ago, and ended 250,000,000 years ago. That is, its duration was approximately 40 million years. Unlike many other geological periods, it was not identified on the British Isles, but in Russia, in the vicinity of the city of Perm.
About climate
The features of animals of the Permian period largely depend on the climate. In those days it was zonal, aridity grew. However, in general, the climate of the Permian period, animals, plants were something close to modern. At least, in comparison with subsequent periods of the Mesozoic, there were more similarities with modern conditions.
In those days, a tropical climate belt was outlined in which the ocean - Tethys was located. In the north there was a belt of hot climate, from which remained saline and red-colored deposits. Even closer to the north was the temperate zone, where coal was accumulating. The beginning of the period is characterized by the continuation of glaciation, which began in the Carboniferous. It was most pronounced in the south. In short, the animals and plants of the Permian period experienced times when the Earth possessed the most extensive deserts of the entire era. In the sand was even Siberia.
About plants
Hercynian mountain formation, which was accompanied by volcanic activity, largely influenced the aromorphoses of plants and animals of the Permian period. Regressed seas, swamps disappeared. The Earth’s surface was dried, and the flora and fauna of the Permian period changed.
Only on the territory of modern China did the geographic conditions remain practically unchanged. Tree-shaped lepidophytes remained from the plant world, but conifers, the first ginkgoids, also began to spread rapidly. Ferns were represented by pecopterids.
In Russia
One of the largest places in which animals and plants of the Permian period were discovered is located in Chekard. Ocherskoe is also known, where the skeletons of many reptiles were found - estemmenozuh, ivantosaurus, camakopsa.
The next known location of fossil remains of plants, animals and insects of the Permian period is Kotelnichesky in the Kirov region. In addition, many fossils were discovered in the Arkhangelsk region.
About the underwater world
Speaking briefly about animals of the Permian period, most of them - about 82%, were vertebrates. The appearance and disappearance of childbirth in those days was very fast, many lived only for 10,000,000 - 20,000,000 years, which is not a long time.
There were many crinoids on the reefs; they created whole underwater "gardens", chained in shells. Over time, many found shells whose flaps closed with each other. Prickly brachiopods lived in the silt. Bivalve mollusks appeared - the ancestors of modern mussels. Between these species, the competition for food represented by bottom sediments was in full swing. With the help of a muscular leg, they could dig into the silt. Bivalves were fed by means of tubes. Some of them managed to learn to swim, like the current scallops, slamming the sink and pushing themselves further in this way. Worm-shaped actively developed.
The most prosperous fish were cartilaginous, plate-branchial, and shark-shaped. In the latter, the teeth were twisted into a spiral. Fresh-water shark-like fish appeared, and the number of brush-fish fell. A small percentage of the fauna of the Permian period were whole-headed. Their current representatives are chimeras. Radiant fish spread, while the life of acanthodes was very sad.
About amphibians
With the beginning of Perm, amphibian dominance on land and in water began, the diversity among them became even greater. Small amphibians coexisted with the giant ancestors of frogs, whose size reached the size of a bull. Four-legged made up 69% of all amphibians. The most prosperous among them were euskelles. Their sizes reached 40 cm - 2 m. Platyhystrix was interesting, which grew a sail on the back for thermoregulation. It was a rarity.
After them came archaeosaurus - they were large, from 1.5 to 9 m, creatures that were not much different from crocodiles. Prionosuchus was one of the largest representatives of the fauna of the Permian period. Soft tissues of the sky of individuals were covered with bone formations on which small denticles were located.
Composing a brief report on animals of the Permian period, it should be noted that the climate of that era was constantly changing, becoming drier. This made amphibians hiding in oases in the middle of deserts. A considerable part of them died out, and reptiles began to actively develop, and soon they accounted for 53% of all four-legged animals. Their first representatives were small, similar to lizards. They fed on vermiform and arthropods. Subsequently, large reptiles began to hunt small ones. They became more predatory and ferocious, armed with teeth, like modern crocodiles.
Oh reptiles
Reptiles began to lay eggs on land. Their embryos passed the stage of the larva due to the fact that the eggs had more nutrients than caviar. Reptiles generally evolved quite quickly, because on land in the Permian period there were not particularly animals. At least those who could compete with them. This class replaced stegocephals.
Cotilosaurs - simple reptiles - captured water, land and air. The sizes of these ancient animals of the Permian period were from frogs to hippos.
A little more difficult were the pareiasaurs 3 meters in size. These were herbivores of the Permian period, inhabiting the banks of rivers and lakes.
The predatory world was personified by pelicosaurs. Their spines had high ridges. Their skin bones gradually disappeared.
The predatory animals of the Permian period were already more and more like wolves, hyenas and martens. In many ways, they were similar to modern representatives of the fauna.
Reptiles of this period are divided into two groups - zavropsida and animal. The former were the ancestors of the present reptiles, and the latter the ancestors of mammals. The sauropsids had no hair, sweat glands, their skin was horny, with armor. In addition, they could easily tolerate a lack of water.
A detachment of Mesosaurs stood out - these are the first reptiles that returned to the water. They were small - up to 1 meter, with needle-shaped teeth that acted as sieves. The mesosaurus filled a mouthful of invertebrates or fish, clenched its jaws, filtered out water through its teeth and swallowed everything in its mouth.
As for diapsids, they accounted for 5% of all genera of that period. Areoscelids were the first evolutionary attempts to produce a land lizard. They began to die out gradually. Archosauromorphs were common - the ancestors of crocodiles up to 2 meters in size, in the appearance of which traits of dinosaurs are traced.
The first flying reptile is coelurosaurus. It resembled a modern flying lizard - the flying dragon Draco volans. He flew excellently through the air, this is an illustration of evolutionary convergence - a process in which creatures that are not connected to each other acquire similar features. The coelurosaurus was 40 cm long, had wings on its sides, and a crest on the back of the head, which gave the creation aerodynamic qualities.
Mammalian ancestors
The world of animals and plants of the Permian period is not conceivable without beast-teeth - the ancestors of mammals. Their teeth varied significantly in their shapes - they were represented by incisors, fangs, molars. The lower jaw was formed from one tooth bone. Due to the presence of secondary bone palate, they could chew food. These mammalian animals resembled the structure of their shoulder blades and pelvis.
The most mobile animal-like reptiles were gorgonops. The legs of the early reptiles resembled the legs of modern lizards - they were located on the sides of the body. But at the Gorgonops, they began to grow under the body, so these animals learned to run faster. Many of them had huge fangs. These were predators.
Synapsids were some of the most prosperous beast-like reptiles. They evolved towards mammals - they raised fangs, hair, sweat glands, learned to maintain a constant body temperature and so on. In this direction there were many branches that did not go far.
The most primitive of them were pelicosaurs. They spread across the Earth very quickly, it was the largest at that time of creation. Pelicosaurus were predators with huge teeth, but some of them switched to plant foods. When considering animals and plants of the Permian period, it is important to consider that plants are digested more slowly, and this leads to an increase in the stomachs of herbivorous animals during evolution. But soon predators began to increase.
The oldest among the herbivores were caseosaurs - their sizes were 1.2 - 6.1 m, and the mass reached 2 tons. Among them, there were species that ate insects. The large size did not save them, and soon almost all of them were eaten by gorgonopses.
One of the most advanced predators of its time was the sphenacodonts, their length reaching 4.5 m.
Deinotsephals were very common, they accounted for 7% of all genera of that period. These were creatures with the largest skulls, powerful bones. In addition, tapinocephals were found - their share was 5% in Permian genera. These were hippo-like creatures 2.5 - 5 m long, they weighed 2 tons.
Most likely, they used their powerful frontal bones, like modern rams with their horns. They didn’t eat grass, since in the Permian period the grass did not grow much, but gnawed the lower branches of ferns, they could eat half-rotted trunks. It is noteworthy that these ancient creatures did not have molars - they chewed food with their front teeth. They were not able to chew and breathe at the same time.
Separately, titanosuchs are isolated. In the photo, the animals of the Permian period, belonging to this species, somewhat resemble boars: they got rid of vegetarianism and, on occasion, could eat carrion and hunt for small prey. For example, on other people's cubs.
The large predators were reminiscent of large predators anteosaurs - they reached 2.5 - 6 meters in length, but at the same time they were distinguished by their harmony - their weight was not more than 600 kg. Curious is the fact that they did not have a palate, but there were separate canals in the skull, due to which they breathed differently than modern animals while eating.
Theiodonts
These creations belonged to the beast-lizard dinosaurs; they had a set of teeth, as in mammals, with incisors, fangs, and molars. Someone's fangs could change an unlimited number of times. Unfortunately, later mammals lost this ability. The majority of theriodonts were gorgonopses - these were the first attempts of nature to create saber-toothed tigers. Not all gorgonops had saber-toothed fangs, usually they hardly exceeded the size of the fangs of modern predators. These were the first creatures that could run fast. They quickly began to dominate everywhere among predators, and the rest began to die out quickly. Their sizes reached 1 - 4.3 meters. Their appearance resembled modern wild dogs, and this is due to the same ecological niche.
It is curious that most of them were first discovered by Russian paleontologists, which led to their names - Vyatkogorgon, Orthodoxy, foreigners (in honor of A. A. Inostrantsev).
Toward the end of the Permian period, dicynodonts appeared. They were mostly not larger than rats, but some of them were the size of a cow. Mostly they lived on land, but a number of them lived in water. Most likely, they had horny beaks resembling turtles.
About warm-blooded
When Perm was nearing completion, many reptiles became warm-blooded. Due to this quality, they could be active longer, there was no need to warm up for a long time after cold nights. To maintain heat, it is important for them to have fast digestion, which will allow them to receive timely thermal energy.
The most advanced theriodont suborder is cynodonts. These are the ancestors of mammals. Their body was already covered with wool, they had the same teeth, with their fangs they tore the prey into pieces, and with their front teeth they seized food. The molars were needed for chewing and grinding food.
Their skull began to possess powerful jaw muscles, the sky appeared, like crocodiles. Thanks to this, they gained the ability to breathe when their mouth is full of food. So they learned to chew food more efficiently. According to one point of view, the platypus and echidna are cynodonts that have survived to this day. In the Permian period they only began to appear. They were small - up to 60 cm - creatures, fed on insects, animals and fish - like otters. These are our distant ancestors.
But as soon as the cynodonts began to spread, the most formidable reptiles - dinosaurs - appeared on the scene. Faced with them, only a small part of the warm-blooded cynodonts survived. They survived only because they were warm-blooded. This allowed them to be active in the cold, at night, when the dinosaurs were inactive.
Many cynodonts died out towards the end of the Permian, but someone lived to see the beginning of the Triassic. The descendants of these creatures survived the dinosaurs and gave rise to a new, most organized group - mammals, which in the future will become rulers of the Earth. In many respects, these difficulties influenced their formation.
It should be borne in mind that reptiles even on the same continents were very different due to differences in climatic zones. Some of the therapsids were not subject to classification - tetracerotopes, phthisuchs, camagorgons remained mysterious creatures that were not assigned to any particular branch.
End of an era
The end of the era was marked by grand cataclysms - a clash of the continents began, the raising of new mountains, the sea, then flooded the land, then went back. There were sharp and frequent climatic changes. The ozone layer of the planet was almost completely destroyed due to the fact that huge portions of hydrogen sulfide and methane were thrown into the atmosphere.
Many living creatures did not adapt to such conditions, they disappeared from the face of the Earth forever. So, more than half of all existing families died. Worst of all was the species that lived in shallow water. Killed more than 90% of terrestrial and 70% of marine animals. The oldest corals died, they were replaced by modern reef-forming corals. Trilobites died out.
Scientists have made many attempts to explain the events. Most likely, the seas disappeared, mountains arose, and the habitual habitat became unbearable for living things. When the continents united, competition increased, and many genera fell victim to it.
Most losses are noted among animals of the oceans. Due to the aridity of the climate, water from rivers and lakes evaporated more and more, and they became salty. In Perm rocks found many salt deposits. This could provoke the extinction of many marine creatures. But now we can only guess about the exact reasons for what happened.