There was no Carboniferous period in the geological history of the earth. Carboniferous period, animals of the Carboniferous period Flora in the Carboniferous period
Carboniferous period (abbreviated carbon (C))
Period duration: period in the Upper Paleozoic 360-299 million years ago,its duration is 65-75 million years; follows the Devonian system and precedes the Permian.
Why is it so named and by whom was it discovered?
Named for the era of coal formation at this time, it left us with a legacy of almost half of the coal reserves available on Earth.
Carboniferous periodestablished in 1822 by W. Conybeare and W. Phillips in Great Britain. In Russia, the studycarboniferous periodand its fossil fauna and flora was carried out by V. I. Meller, S. N. Nikitin, F. N. Chernyshev and others, and in Soviet times by M. D. Zalessky, A. P. and E. A. Ivanovs, D. V. Nalivkin, M. S. Shvetsov, M. E. Yanishevsky, L. S. Librovich, S. V. Semikhatova, D. M. Rauzer-Chernousova, A. P. Rotai, V. E. Ruzhentsev, O. L. Einor and others. In Western Europe, the most important studies were carried out by the English scientist A. Vaughan, the German paleobotanist W. Gotan, and others. In North America, by C. Schuchert, C. Dunbar, and others.
From the history:at the beginning of the Carboniferous period (Carboniferous), most of the earth's land was collected into two huge supercontinents: Laurasia in the north and Gondwana in the south. For the first time, the outlines of the greatest supercontinent in the history of the Earth - Pangea - appear. Pangea was formed by the collision of Laurasia (North America and Europe) with the ancient southern supercontinent Gondwana. Shortly before the collision, Gondwana turned clockwise, so that its eastern part (India, Australia, Antarctica) moved to the south, and the western part (South America and Africa) moved to the north. As a result of the turn, a new ocean, the Tethys, appeared in the east, and the old one, the Rhea ocean, closed in the west. At the same time, the ocean between the Baltic and Siberia was getting smaller; soon these continents also collided. The climate cooled noticeably, and while Gondwana "swam" over the South Pole, the planet experienced at least two epochs of glaciation.
Subdivision of the coal system
The Carboniferous period is subdivided into 2 subsystems, 3 divisions and 7 tiers:
Period (system) | Subsystem (Supra-Department) | Epoch (department) | Age (tier) |
Carboniferous period | Pennsylvania | Upper Carboniferous | Gzhel |
Kasimovsky |
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Medium carbon | Moscow |
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Bashkir |
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Mississippi | Lower Carboniferous | Serpukhov |
|
Visean |
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tournaisian |
general characteristics . Carboniferous deposits are common on all continents. Classical sections are in Western Europe (Great Britain, Belgium, Germany) and Eastern Europe (Donbass, Moscow syneclise), North America (Appalachians, Mississippi river basin, etc.). In the Carboniferous, the mutual arrangement of platforms and geosynclines remained the same as in the Devonian.
On the platforms of the Northern Hemisphere, the Carboniferous is represented by marine sediments (limestone, sandy-argillaceous, often coal-bearing sediments). In the Southern Hemisphere, predominantly continental deposits are developed - detrital and glacial (often tillites). Lavas, tuffs and tuffites, siliceous coarse clastic sediments, and flysch are also common in geosynclines.
According to the nature of geological processes and paleogeographical conditions, the Carboniferous almost throughout the entire globe is divided into two stages: the first of them covers the Early Carboniferous, the second - the Middle and Late. In the vast areas of geosynclines of the Middle Paleozoic, due to the Hercynian folding, the marine regime changed to continental after the Early Carboniferous. On S.-E. Asia, the East European and North American platforms, the sea in some places captured the recently formed land areas. The Carboniferous period belongs to the thalassocratic period: the vast expanses within the modern continents were covered by the sea. Submergences and transgressions caused by them occurred repeatedly during the period. The greatest transgressions occurred in the first half of the period. In the early Carboniferous, the sea covered Europe (excluding Scandinavia and adjacent regions), most of Asia, North America, the extreme west of South America, N.-W. Africa, eastern Australia. The seas were mostly shallow with numerous islands. The largest single land mass was Gondwana. A markedly smaller landmass stretched from Scandinavia through the North Atlantic, Greenland and North America. The land was also the central part of Siberia between the river. Lena and Yenisei, Mongolia and the Laptev Sea. By the Middle Carboniferous, the sea had left almost all of Western Europe, the West Siberian Plain, Kazakhstan, Central Siberia, and other regions.
In the 2nd half - in the zones of the Hercynian orogeny (Tien Shan, Kazakhstan, the Urals, the northwestern part of Europe, East Asia, North America), mountain ranges rose.
Climatecontinents was diverse and changed from century to century. Its common feature was the high humidity of the tropical, subtropical and temperate zones, which contributed to the widespread distribution of forest and marsh vegetation on all continents. The accumulation of plant residues, mainly in peatlands, led to the formation of numerous coal basins and deposits.
The identification of the following phytogeographic regions is accepted, Euramerian, or Westphalian (tropical and subtropical), Angara, or Tunguska (extratropical), Gondwanal (temperate). The climate of the Euramerian region by the end of the Carboniferous became drier, in some places subarid. The remaining areas retained their high humidity not only until the end, but also in the Permian period. The highest humidity and optimal conditions for peat accumulation (coal accumulation) in the Euramerian region were: in the Greater Donbass at the end of the Early, Middle Carboniferous, in Western Europe - in Namur - Westphalian, in North America - in the Middle and Upper Carboniferous, in Kazakhstan - in the Late Vize - Middle Carboniferous. In the south of the Angarsk region (Kuzbass and other depressions), intensive growth of peatlands occurred from the Middle Carboniferous, and in Gondwana, from the Late Carboniferous to the end of the Permian. The dry climate was typical only for a limited area. For example, in the Tournaisian age, one of the arid climate zones stretched from southern Kazakhstan through the Tien Shan to the Tarim massif.
organic world. At the very beginning of the period, the flora was dominated by small-leaved lycopsids, gymnosperms of ferns (pteridosperms), primitive arthropods and ferns (mainly great-ferns). Even in the Early Carboniferous, the primitive lycopods were replaced by large tree-like ones, which were especially widespread in the Middle Carboniferous. In the tropics (Euramerian region), in the Middle Carboniferous, forests of tall lycopods with a large number of pteridosperms and other ferns, calamites, and cuneiformes dominated. To the north (Angara region), in the Early Carboniferous, lycopsids dominated, and in the middle, Late Carboniferous, cordaites and ferns dominated. In the Gondwana region at that time, apparently, the so-called glossopteris flora, which was especially characteristic of the Permian, had already developed. In the phytogeographic regions of the temperate climate, a relatively gradual development of the flora from the Middle Carboniferous to the early Permian was observed. On the contrary, in the tropics in the Late Carboniferous, in some places, under the influence of climate aridization, a radical change occurred in the vegetation of marshy lowlands. The main plant groups were pteridosperms and tree ferns. Conifers spread on elevated places. In the seas of the Carboniferous there were blue-green algae, in fresh waters - green algae-coal-formers.
Animal world. The Carboniferous period is very diverse. Foraminifera were widespread in the seas, experiencing rapid evolutionary changes throughout the period and giving rise to many tens of genera and thousands of species. Rugoses, tabulates, and stromatoporoids still prevailed among the coelenterates. Mollusks (bivalves, gastropods), rapidly evolving ammonoid cephalopods were diverse. Some bivalves existed in heavily desalinated lagoons and deltas, which allows them to be used for stratigraphy of coal-bearing strata. Brachiopods were widespread in shallow seas. Some areas of the seabed were especially favorable for the development of bryozoans; arthropods are varied. Of the echinoderms, sea lilies developed abundantly, the segments of which form entire layers in the limestone strata, in some places the remains of sea urchins are often found, and blastoids are rare.
Different classes of vertebrates, especially fish (marine and freshwater), have gone through a significant evolutionary path. Bone fish, sharks develop. Amphibians and stegocephalians dominated on land; reptiles were still rare. The remains of numerous insects (mayflies, dragonflies, cockroaches) were found, some of them reached gigantic sizes. Towards the end of the Carboniferous, a new group of four-legged animals appeared in the vast forests. Basically, they were small and in many ways resembled modern lizards, which is not surprising: after all, they were the first reptiles (reptiles) on Earth. Their skin, more moisture-resistant than that of amphibians, gave them the opportunity to spend their whole lives out of the water. There was plenty of food for them: worms, centipedes and insects were at their complete disposal. And after a relatively short time, larger reptiles also appeared, which began to eat their smaller relatives. Carboniferous insects were the first creatures to take to the air, and they did so 150 million years before birds. Dragonflies were the pioneers. Soon they turned into the "kings of the air" coal marshes. The wingspan of some dragonflies reached almost a meter. Butterflies, moths, beetles and grasshoppers followed suit.
Minerals : hard and brown coal form a number of basins and deposits on all continents, confined to the Hercynian marginal troughs and internal depressions. In the USSR, the basins are: Donetsk (hard coal), Moscow region (brown coal), Karaganda (hard coal), Kuznetsk and Tunguska (Carboniferous and Permian coals); deposits of Ukraine, the Urals, the North Caucasus, etc. In Central and Western Europe, basins and deposits of Poland (Silesia), the GDR and the FRG (Ruhr), Belgium, the Netherlands, France, Great Britain are known; in the USA, the Pennsylvania and other basins. Many oil and gas fields are confined to the Carboniferous (Volga-Ural region, Dnieper-Donetsk depression, etc.). There are also many deposits of ores of iron, manganese, copper (the largest is Dzhezkazgan), lead, zinc, aluminum (bauxite), refractory and ceramic clays.
From 360 to 286 million years ago.
At the beginning of the Carboniferous period (Carboniferous), most of the earth's land was collected into two huge supercontinents: Laurasia in the north and Gondwana in the south. During the Late Carboniferous, both supercontinents steadily approached each other. This movement pushed up new mountain ranges that formed along the edges of the earth's crust plates, and the edges of the continents were literally flooded with lava flows erupting from the bowels of the Earth. The climate cooled noticeably, and while Gondwana "swam" over the South Pole, the planet experienced at least two epochs of glaciation.
In the early Carboniferous, the climate over most of the earth's land surface was almost tropical. Huge areas were occupied by shallow coastal seas, and the sea constantly flooded the low coastal plains, forming vast swamps there. In this warm and humid climate, virgin forests of giant tree ferns and early seed plants are widespread. They released a lot of oxygen, and by the end of the Carboniferous, the oxygen content in the Earth's atmosphere had almost reached its present level.
Some of the trees that grew in these forests reached 45 m in height. The plant mass increased so rapidly that the invertebrates that lived in the soil simply did not have time to eat and decompose dead plant material in time, and as a result, it became more and more. In the humid climate of the Carboniferous period, thick peat deposits formed from this material. In swamps, peat quickly went under water and turned out to be buried under a layer of sediment. Over time, these sedimentary layers turned into coal-bearing
shchi deposits of sedimentary rocks, interbedded with coal, formed from the petrified remains of plants in peat.
Reconstruction of the coal bog. Many large trees grow here, including sigillaria (1) and giant club mosses (2), as well as dense thickets of calamites (3) and horsetails (4), an ideal habitat for early amphibians like ichthyostega (5) and crinodon (6) . Arthropods swarm all around: cockroaches (7) and spiders (8) scurry in the undergrowth, and giant dragonflies meganeurs (9) with an almost meter wingspan plow the air above them. Due to the rapid growth of such forests, a lot of dead leaves and wood accumulated, which sank to the bottom of the marshes before they had time to decompose, and over time turned into peat, and then into coal.
Insects are everywhere
At that time, plants were not the only living organisms that developed land. Arthropods also emerged from the water and gave rise to a new group of arthronodes, which turned out to be extremely viable, insects. Since the very first appearance of insects on the stage of life, their triumphal procession has begun, but
planet. Today, there are at least a million species of insects known to science on Earth, and, according to some estimates, about 30 million more species remain to be discovered by scientists. Indeed, our time could be called the era of insects.
Insects are very small and can live and hide in places inaccessible to animals and birds. The bodies of insects are designed so that they easily master any means of movement - swimming, crawling, running, jumping, flying. Their hard outer skeleton - cuticle (consisting of a special substance - chitin) -
passes into the oral part, capable of chewing hard leaves, sucking out vegetable juices, and also piercing the skin of animals or biting prey.
HOW COAL IS FORMED.
1. Carboniferous forests grew so fast and wildly that all the dead leaves, branches and trunks of trees that accumulated on the ground simply did not have time to rot. In such "coal bogs" layers of dead plant remains formed deposits of water-soaked peat, which was then compressed and turned into coal.
2. The sea advances on land, forming deposits on it from the remains of marine organisms and layers of silt, which subsequently turn into shale.
3. The sea recedes and the rivers deposit sand on top of the shales, from which sandstones are formed.
4. The terrain becomes more swampy, and silt is deposited on top, suitable for the formation of clayey sandstone.
5. The forest grows again, forming a new coal seam. This alternation of layers of coal, shale and sandstone is called the coal-bearing strata.
Great Carboniferous Forests
Among the lush vegetation of the Carboniferous forests, huge tree-like ferns up to 45 m high, with leaves longer than a meter, prevailed. In addition to them, giant horsetails, club mosses and recently emerged seed-bearing plants grew there. The trees had an extremely shallow root system, often branching above the surface.
soil, and they grew very close to each other. Probably, everything around was littered with fallen tree trunks and heaps of dead branches and leaves. In this impenetrable jungle, plants grew so fast that the so-called ammonifiers (bacteria and fungi) simply could not keep up with the decay of organic remains in the forest soil.
In such a forest it was very warm and humid, and the air was constantly saturated with water vapor. Many backwaters and swamps provided ideal breeding grounds for countless insects and early amphibians. The air was filled with the buzzing and chirping of insects - cockroaches, grasshoppers and giant dragonflies with a wingspan of almost a meter, and the undergrowth was teeming with silverfish, termites and beetles. The first spiders had already appeared, numerous centipedes and scorpions scurried along the forest floor.
Fragment of a fossilized fern Aletopteris from the coal-bearing strata. Ferns thrived in damp and humid Carboniferous forests, but they proved ill-adapted to the more arid climate that developed during the Permian period. Germinating, fern spores form a thin fragile plate of cells - prothallium, in which male and female reproductive organs are produced over time. Prothallium is extremely sensitive to moisture and dries quickly. Moreover, male reproductive cells, spermatozoa, secreted by prothallium, can only reach the female egg through a water film. All this interferes with the spread of ferns, forcing them to stick to a humid habitat, where they are found to this day.
Plants of coal marshes
The flora of these vast forests would seem very strange to us.
Ancient lycopod plants, relatives of modern lycopsins, looked like real trees - 45 m high. Heights up to 20 m reached the top of giant horsetails, strange plants with rings of narrow leaves growing directly from thick articulated stems. There were also ferns the size of a good tree.
These ancient ferns, like their living descendants, could only exist in humid areas. Ferns reproduce by producing hundreds of tiny spores in a hard shell, which are then carried by air currents. But before these spores develop into new ferns, something special must happen. First, tiny fragile gametophytes (plants of the so-called sexual generation) grow from spores. They, in turn, give birth to small cups containing male and female germ cells (sperm and eggs). To swim up to the egg and fertilize it, sperm need a water film. And only then can a new fern develop from a fertilized egg, the so-called sporophyte (asexual generation of the plant life cycle).
Meganeurs were the largest dragonflies that ever lived on Earth. Moisture-saturated coal forests and swamps provided shelter for many smaller flying insects, which served as easy prey for them. The enormous compound eyes of dragonflies give them an almost circular view, allowing them to pick up the slightest movement of a potential prey. Perfectly adapted for aerial hunting, dragonflies have undergone very minor changes over the past hundreds of millions of years.
seed plants
Fragile gametophytes can only survive in very humid places. However, by the end of the Devonian period, seed ferns appeared - a group of plants that managed to overcome this shortcoming. Seed ferns resembled modern cycads or cyatheas in many ways and reproduced in the same way. Their female spores remained on the plants that gave birth to them, and there they formed small flask-shaped structures (archegonia) containing eggs. Instead of floating sperm, seed ferns produced pollen carried by air currents. These pollen grains germinated into female spores and released male germ cells into them, which then fertilized the egg. Now plants could finally master the arid regions of the continents.
The fertilized egg developed inside a cup-shaped structure, the so-called ovule, which then turned into a seed. The seed contained reserves of nutrients, and the embryo could germinate quickly.
Some plants had huge cones up to 70 cm long, which contained female spores and formed seeds. Now plants could no longer depend on water, through which previously male sex cells (gametes) had to get to the eggs, and the extremely vulnerable gametophyte stage was excluded from their life cycle.
Warm swamps of the Late Carboniferous abounded with insects and amphibians. Butterflies (1), giant flying cockroaches (2), dragonflies (3) and mayflies (4) fluttered among the trees. Giant bipedal centipedes feasted in the rotting vegetation (5). Centipedes hunted on the forest floor (6). Eogyrinus (7) - large, up to 4.5 m long, amphibian - may have hunted in the manner of an alligator. A 15-cm microbrachia (8) fed on the smallest animal plankton. The tadpole-like Branchiosaurus (9) had gills. Urocordilus (10), Sauropleura (1 1) and Scincosaurus (12) looked more like newts, but the legless dolichosome (13) looked a lot like a snake.
Amphibious time
The bulging eyes and nostrils of the first amphibians were located at the very top of a wide and flat head. Such a "design" turned out to be very useful when swimming on the water surface. Some of the amphibians may have stalked prey half submerged in the water - in the manner of today's crocodiles. Perhaps they looked like giant salamanders. They were formidable predators with hard and sharp teeth, with which they grabbed their prey. A large number of their teeth have been preserved as fossils.
Evolution soon gave rise to many diverse forms of amphibians. Some of them reached 8 m in length. The larger ones still hunted in the water, while their smaller counterparts (microsaurs) were attracted by the abundance of insects on land.
There were amphibians with tiny legs or no legs at all, something like snakes, but without scales. They may have spent their entire lives buried in mud. Microsaurs looked more like small lizards with short teeth, with which they split the covers of insects.
Nile crocodile embryo inside an egg. Such eggs, resistant to desiccation, protect the embryo from shocks and contain enough food in the yolk. These properties of the egg allowed the reptiles to become completely independent of water.
The first reptiles
Towards the end of the Carboniferous, a new group of four-legged animals appeared in the vast forests. Basically, they were small and in many ways resembled modern lizards, which is not surprising: after all, they were the first reptiles (reptiles) on Earth. Their skin, more moisture-resistant than that of amphibians, gave them the opportunity to spend their whole lives out of the water. There was plenty of food for them: worms, centipedes and insects were at their complete disposal. And after a relatively short time, larger reptiles also appeared, which began to eat their smaller relatives.
Everyone has their own pond
Reptiles no longer need to return to the water to breed. Instead of throwing soft eggs that hatched into floating tadpoles, these animals began to lay eggs in a hard, leathery shell. The hatchlings hatched from them were exact miniature copies of their parents. Inside each egg there was a small sac filled with water, where the embryo itself was placed, another sac with the yolk on which it ate, and finally a third sac where the feces accumulated. This shock-absorbing layer of liquid also protected the fetus from shock and damage. The yolk contained many nutrients, and by the time the baby hatched, he no longer needed a reservoir (instead of a bag) for ripening: he was already old enough to get his own food in the forest.
rum. If you move them up and down, you could warm up even faster - let's say you and I warm up when running in place. These "flaps" got bigger and bigger, and the insect began to use them to glide from tree to tree, possibly escaping predators such as spiders.
FIRST FLIGHT
Carboniferous insects were the first creatures to take to the air, and they did so 150 million years before birds. Dragonflies were the pioneers. Soon they turned into the "kings of the air" coal marshes. The wingspan of some dragonflies reached almost a meter. Butterflies, moths, beetles and grasshoppers followed suit. But how did it all start?
In the damp corners of your kitchen or bathroom, you may have noticed small insects - they are called scales (right). There is a variety of silverfish, from the bodies of which a pair of tiny plates protrude, resembling flaps. Perhaps some similar insect became the ancestor of all flying insects. Maybe it spread these records in the sun to quickly warm up in the early morning.
Huge deposits of coal are found in the deposits of this period. Hence the name of the period. There is another name for it - carbon.
The Carboniferous period is divided into three sections: lower, middle and upper. During this period, the physical and geographical conditions of the Earth underwent significant changes. The outlines of the continents and seas repeatedly changed, new mountain ranges, seas, and islands arose. At the beginning of the Carboniferous, a significant subsidence of the land takes place. The vast areas of Atlantia, Asia, and Rondwana were flooded by the sea. The area of large islands has decreased. Disappeared under water deserts of the northern continent. The climate became very warm and humid,
In the Lower Carboniferous, an intensive mountain-building process begins: the Ardepny, Gary, Ore Mountains, Sudetes, Atlasspe Mountains, Australian Cordillera, and West Siberian Mountains are formed. The sea is receding.
In the middle Carboniferous, the land descends again, but much less than in the lower one. Thick strata of continental deposits accumulate in intermountain basins. Formed Eastern Ural, Penninskis mountains.
In the Upper Carboniferous, the sea recedes again. Inland seas are significantly reduced. On the territory of Gondwana, large glaciers appear, in Africa and Australia, somewhat smaller ones.
At the end of the Carboniferous in Europe and North America, the climate undergoes changes, becoming partly temperate, and partly hot and dry. At this time, the formation of the Central Urals takes place.
Marine sedimentary deposits of the Carboniferous period are mainly represented by clays, sandstones, limestones, shales and volcanogenic rocks. Continental - mainly coal, clays, sands and other rocks.
Intensified volcanic activity in the Carboniferous led to the saturation of the atmosphere with carbon dioxide. Volcanic ash, which is a wonderful fertilizer, made fertile carboxylic soils.
A warm and humid climate prevailed on the continents for a long time. All this created extremely favorable conditions for the development of terrestrial flora, including higher plants of the Carboniferous period - bushes, trees and herbaceous plants, whose life was closely connected with water. They grew chiefly among vast swamps and lakes, near brackish lagoons, on the shores of the seas, on damp muddy soil. In their way of life, they resembled modern mangroves that grow on the low-lying shores of tropical seas, at the mouths of large rivers, in swampy lagoons, rising above the water on high stilted roots.
Significant development in the Carboniferous period was received by lycopods, arthropods and ferns, which gave a large number of tree-like forms.
Tree-like lycopods reached 2 m in diameter and 40 m in height. They didn't have annual rings yet. An empty trunk with a powerful branched crown was securely held in loose soil by a large rhizome, branching into four main branches. These branches, in turn, were dichotomously divided into root processes. Their leaves, up to a meter in length, adorned the ends of the branches with thick plump-shaped bunches. At the ends of the leaves there were buds in which spores developed. Trunks of lycopods were covered with scarred scales. Leaves were attached to them. During this period, giant club-shaped lepidodendrons with rhombic scars on the trunks and sigillaria with hexagonal scars were common. In contrast to most club-like sigillaria, there was an almost unbranched trunk on which sporangia grew. Among the lycopods there were also herbaceous plants, which completely died out in the Permian period.
Articular plants are divided into two groups: cuneiform and calamites. Cuneiformes were aquatic plants. They had a long, jointed, slightly ribbed stem, to the nodes of which leaves were attached in rings. Reniform formations contained spores. Cuneiformes kept on the water with the help of long branched stems, similar to the modern water ranunculus. Cuneiformes appeared in the middle Devonian and died out in the Permian period.
Calamites were tree-like plants up to 30 m tall. They formed swamp forests. Some types of calamites penetrated far to the mainland. Their ancient forms had dichotomous leaves. Subsequently, forms with simple leaves and annual rings prevailed. These plants had a highly branched rhizome. Often, additional roots and branches covered with leaves grew from the trunk.
At the end of the Carboniferous, the first representatives of horsetails appear - small herbaceous plants. Among the carboxylic flora, ferns played a prominent role, in particular herbaceous ones, but reminiscent of psilophytes in their structure, and real ferns, large tree-like plants, fixed by rhizomes in soft soil. They had a rough trunk with numerous branches on which grew broad fern-like leaves.
Gymnosperms of carbon forests belong to the subclasses of seed ferns and stachyospermids. Their fruits developed on leaves, which is a sign of primitive organization. At the same time, linear or lanceolate leaves of gymnosperms had a rather complex vein formation. The most perfect plants of the Carboniferous are cordaites. Their cylindrical leafless trunks up to 40 m branched in height. The branches had wide, linear or lanceolate leaves with reticulate venation at the ends. Male sporangia (microsporangia) looked like kidneys. Nut-shaped sporangia developed from female sporangia: . fruit. The results of microscopic examination of the fruits show that these plants, similar to cycads, were transitional forms to coniferous plants.
The first mushrooms, moss-like plants (terrestrial and freshwater), sometimes forming colonies, and lichens appear in the coal forests.
In marine and freshwater basins, algae continue to exist: green, red and char.
When considering the Carboniferous flora as a whole, the variety of forms of leaves of tree-like plants is striking. Scars on the trunks of plants throughout life kept long, lanceolate leaves. The ends of the branches were decorated with huge leafy crowns. Sometimes leaves grew along the entire length of the branches.
Another characteristic feature of the Carboniferous flora is the development of an underground root system. Strongly branched roots grew in the silty soil and new shoots grew from them. At times, significant areas were cut by underground roots.
In places of rapid accumulation of silty sediments, the roots held the trunks with numerous shoots. The most important feature of the Carboniferous flora is that the plants did not differ in rhythmic growth in thickness.
The distribution of the same carboniferous plants from North America to Spitsbergen indicates that a relatively uniform warm climate prevailed from the tropics to the poles, which was replaced by a rather cool one in the Upper Carboniferous. Gymnosperms and cordaites grew in a cool climate.
The Carboniferous period is the period of the Earth, when forests of real trees turned green on it. Herbaceous plants and plants resembling bushes already existed on Earth. However, forty-meter giants with trunks up to two meters thick have appeared only now. They had powerful rhizomes, allowing the trees to hold firmly in soft, moisture-saturated soil. The ends of their branches were decorated with bunches of meter-long pinnate leaves, on the tips of which fruit buds grew, and then spores developed.
The emergence of forests became possible due to the fact that in the Carboniferous a new offensive of the sea began on land. The vast expanses of the continents in the Northern Hemisphere turned into marshy lowlands, and the climate remained hot as before. Under such conditions, vegetation developed unusually rapidly. The forest of the Carboniferous period looked rather gloomy. Stuffiness and eternal twilight reigned under the crowns of huge trees. The soil was a marshy bog, saturating the air with heavy vapors. In the thickets of calamites and sigillaria floundered clumsy creatures resembling salamanders in appearance, but many times their size - ancient amphibians.
Kordaites
Cordaites reproduced by seeds that matured in special organs - strobili, collected in earrings. These earrings were the prototype of real flowers, which appeared much later. The descendants of club mosses, lepidodendrons, had a ribbed trunk with a bark pierced by a network of air channels. The scars on the trunks were traces of fallen leaves and retained a diamond shape. And in sigillaria, covered with foliage resembling bristles, the scars on the trunks were hexagonal. The wood of these plants did not yet have annual rings, since there were no noticeable differences between seasons.
Kalamita
In the air, heavy with moisture, gigantic, with a wingspan of up to a meter, predatory dragonflies swept; huge spiders, similar to modern harvesters, hid in the dark, waiting for prey. Scorpions and cockroaches the size of a lap dog came across at every turn. Carboniferous insects had much in common with trilobites in their structure. But they did not originate from trilobites, but from terrestrial arthropods. Ferns reached an unprecedented flourishing of the Carboniferous period. They were found everywhere - both in forests and in meadows. These were Carboniferous plants of a wide variety of shapes and colors from light green to almost black. Many of them have become mighty trees with a thick trunk and dense feathery crown.
Neither earlier nor later on Earth was there such a variety of vegetation as the flora of the Carboniferous period had. But, like all living things, the plants of the Carboniferous period completed their development and died. Their remains fell into the shallow water of the lagoons, dragged on with silt, and various microorganisms began their unhurried work in these accumulations of organic matter. Plant residues were fermented, a large amount of gas was released, and organic matter was charred.
After millions of years, the plants of the carbon forests have turned into coal of various kinds. Where once there were thickets of horsetails, coal with a high sulfur content is now mined; algae and aquatic plants formed layers of coal with a high content of paraffin. Fat coals, coals with a long flame, coking coals - the grades of coal depend on the composition of the plants from which they were formed.
Over time, the coal seams were covered with layers of clay and shale, and many of them perfectly preserved the imprints of leaves, branches, seeds and other plant organs of the Carboniferous period. Coal deposits now resemble a grandiose layer cake, occupying entire regions of the land.
cycads
In the Permian period, cycads appeared - small trees with bunches of leaves on top. Their seeds were already ripening in cones similar to spruce and cedar.
Perm araucaria
The easiest to cope with the drought were araucaria, very similar to those that grow now near the coast of Australia, and ancient pines.
Fauna of the Carboniferous period. Carbon is characterized by the appearance of invertebrates. Among these, we note foraminifer and pulmonary gastropods. We also note the beginning of the life of vertebrates, in particular, this applies to reptiles. In parallel with this, some species became extinct, such as mollusks, graptolites and echinoderms.
Let's talk about such a large group as reptilomorphs. Only a few species preferred water, while all the rest lived on land. Many of these representatives already laid eggs, although until recently they spawned. Ready-made animals were born from the shell, which had only to reach the optimal size. If we take into account the Carboniferous period, then these animals were "kings". They differed in ears and nostrils. The largest individuals were ophiacodonts, their body length was 1.3 m. They somewhat resembled modern lizards in appearance.
Edaphosaurus were even larger. These are large herbivorous vertebrates. Some of them featured a folding sail that helped the animal control its temperature. The length of such animals reached 3.5 meters, and the mass was 300 kg. No less interesting was the underwater fauna. 11% of all available genera were lobe-finned fishes. The most common were coelacanths and tetrapodomorphs. After some time, cartilaginous fish appeared, which just won the competition from carpal fish. Most of them belonged to the subclass of plastic gills. By the way, at that time there were quite a few sharks compared to other animals of the Carboniferous period. Although it is worth considering the fact that then they had a completely different structure. Therefore, they could not oust their neighbors.
Fortunately for people, today there is no longer a dental spiral that lived in the Carboniferous period. This underwater animal was characterized by a long outgrowth coming out of the lower jaw. Teeth grew over its entire area, which folded into a spiral. Paleontologists do not know what role this body part played. There is an assumption according to which this spiral was fired, and the prey was planted on the teeth. Although no one has come to a consensus, therefore the issue on this topic will always be discussed.
Also, one cannot leave aside the xenacanthids, which represented a detachment of sharks. Their sizes were quite small, the maximum length was 3 m. Most of all, the researchers managed to get information about the pleura. It is known that they lived in the fresh waters of America, Europe and Australia. Despite their relatively small size, they posed a threat to acanthodia. He dismembered fish with his sharp teeth. It was not difficult to catch an individual, since this species lived in a flock. Scientists believe that there was a membrane between the laid eggs. Its dimensions were very small, only 40 cm. But half of this length was occupied by the snout. Scientists themselves do not know what role this part of the body played in nature. Perhaps the animal was looking for food due to poor eyesight. These individuals were found both in salt and fresh waters.
The Carboniferous period brought changes to the life of insects. After all, it was in carbon that they began to fly. For comparison, we note that the bird first took to the air after 150 million years. Dragonflies of the Carboniferous period acquired a wonderful appearance. After some time, they became the kings of the air and often met near the swamps. In some individuals, the wingspan reached 90 cm. After that, butterflies, grasshoppers and moths took to the air.
It is interesting to learn how insects began to fly. You may have encountered very small and harmless insects in the damp parts of the kitchen. So they are called scales. If we examined these individuals under a microscope, we would notice tiny plates that look like flaps. Most likely, the dragonfly was able to straighten the plate in order to warm up in the morning. Well, later the insect used this part of the body to its full potential.
Amphibians of the Carboniferous period began their lives. In the process of evolution, they turned from lobe-finned fish. From that moment on, a new class appeared - reptiles. To date, the most common detachment of caudate. They have retained their original appearance.
Interesting changes have taken place in terms of relief. All land was collected in 2 continents: Gondwana and Laurasia. The Carboniferous period of the Paleozoic era is characterized by the constant convergence of these parts of the land surface of the Earth. After their collision, mountain ranges were formed. Let us also note the climate of the Carboniferous period, which became noticeably colder.
The name of this period speaks for itself, since in this geological time period conditions were created for the formation of deposits of coal and natural gas. However, the Carboniferous period (359-299 million years ago) was also notable for the appearance of new terrestrial vertebrates, including the very first amphibians and lizards. Carbon became the penultimate period (542-252 million years ago). It was preceded by , and , and then it was replaced by .
Climate and geography
The global climate of the Carboniferous period was closely related to it. During the preceding Devonian period, the northern supercontinent Laurussia merged with the southern supercontinent Gondwana, creating the huge supercontinent Pangea, which occupied most of the southern hemisphere during the Carboniferous. This had a marked effect on air and water circulation patterns, resulting in much of southern Pangea being covered in glaciers and a general trend towards global cooling (which, however, had little effect on coal formation). Oxygen made up a much higher percentage of the Earth's atmosphere than today, which has affected the growth of terrestrial megafauna, including dog-sized insects.
Animal world:
Amphibians
Our understanding of life during the Carboniferous is complicated by the "Rohmer gap" - a 15 million time span (from 360 to 345 million years ago), which provided little to no fossil information. However, we do know that by the end of this gap, the very first Late Devonian, which had only recently evolved from lobe-finned fishes, had lost their internal gills and were on their way to becoming true amphibians.
By the late Carboniferous, such important genuses from the point of view of evolution as Amphibamus And Phlegethontia, which (like modern amphibians) needed to lay their eggs in the water and constantly moisturize their skin, and therefore could not go too far on land.
reptiles
The main feature that distinguishes reptiles from amphibians is their reproductive system: reptile eggs are better able to withstand dry conditions and therefore do not need to be laid in water or moist soil. The evolution of reptiles was driven by the increasingly cold, dry climate of the Late Carboniferous; one of the earliest identified reptiles, Hylonomus ( Hylonomus), appeared about 315 million years ago, and the giant (almost 3.5 meters long) ophiacdon ( Ophiacodon) evolved several million years later. By the end of the Carboniferous, reptiles migrated well to the interior of Pangea; these early discoverers were descendants of archosaurs, pelycosaurs, and therapsids from the subsequent Permian period (archosaurs would go on to give rise to the first dinosaurs nearly a hundred million years later).
Invertebrates
As noted above, the Earth's atmosphere contained an unusually high percentage of oxygen during the Late Carboniferous, reaching an astounding 35%.
This feature was useful for terrestrial creatures such as insects, which breathed using air diffusion through their exoskeleton, rather than using lungs or gills. Carboniferous was the heyday of the giant dragonfly Meganeura ( Megalneura) with a wingspan of up to 65 cm, as well as the giant Arthropleura ( Arthropleura), reaching almost 2.6 m in length.
Sea life
With the disappearance of the distinctive placoderms (plate-skinned fish) at the end of the Devonian period, the Carboniferous is not well known for its existence, except where some genera of lobe-finned fish were closely related to the very first tetrapods and amphibians to colonize land. Falcatus, a close relative of the Stetecants ( Stethacanthus) was probably the most famous carboniferous shark along with the much larger Edestus ( Edestus), which is known for its distinctive teeth.
As in previous geologic periods, small invertebrates such as corals, crinoids, and crinoids lived in abundance in the Carboniferous seas.
Vegetable world
The dry, cold conditions of the late Carboniferous period were not particularly favorable for flora, but this did not prevent such hardy organisms as plants from colonizing every available one. Carbon has witnessed the very first plants with seeds, as well as bizarre genera such as Lepidodendron, up to 35m high, and the slightly smaller (up to 25m high) Sigallaria. The most important plants of the Carboniferous were those that lived in the carbon-rich "coal swamps" near the equator, and millions of years later they formed the huge coal deposits used by mankind today.