Flora in the Carboniferous period. There was no Carboniferous period in the geological history of the earth

The Carboniferous period (Carboniferous), the fifth period of the Paleozoic era. It lasted about 74 million years. It began 360 million years ago and ended 286 million years ago. The continents in this period were mainly collected in two massifs - Laurasia in the north and Gondwana in the south. Gondwana moved towards Laurasia, and in the areas of contact of these plates, mountain ranges were uplifted.

The Carboniferous period is the period of the Earth, when forests of real trees turned green on it. already existed on earth herbaceous plants and plants resembling bushes. 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.

Nautical animal world Carboniferous was characterized by a variety of species. Foraminifera were extremely common, in particular fusulinids with fusiform shells the size of a grain.
Schwagerins appear in the Middle Carboniferous. Their spherical shell was the size of a small pea. From the shells of foraminifers of the Late Carboniferous, limestone deposits were formed in some places.
Among the corals, there were still a few genera of tabulates, but the hatetids began to predominate. Solitary corals often had thick calcareous walls, Colonial corals formed reefs.
At this time, echinoderms develop intensively, in particular sea lilies and sea urchins, which occupied 4% of all genera of the Carboniferous. Numerous colonies of bryozoans sometimes formed thick limestone deposits.

The brachiopod molluscs developed extremely; their diversity reached 11% of all genera of the Carboniferous. In particular, the productus, in terms of adaptability and geographical distribution, far exceeded all the brachiopods found on Earth. The size of their shells reached 30 cm in diameter. One shell flap was convex, and the other was in the form of a flat lid. The straight elongated hinge edge often had hollow spines. In some forms of productus, the spines were four times the diameter of the shell. With the help of spines, the produktus held on to the leaves of aquatic plants, which carried them downstream. Sometimes, with their spikes, they attached themselves to sea lilies or algae and lived near them in a hanging position. In richtofenia, one shell valve was transformed into a horn up to 8 cm long.

Sea lily. Photo: spacy000

In the lakes of the Carboniferous period, arthropods (crustaceans, scorpions, insects) appear, including 17% of all genera of the Carboniferous. Insects that appeared in the Carboniferous occupied 6% of all animal genera.
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. Butterflies, moths, beetles and grasshoppers followed suit.
Carboniferous insects possessed the features of many genera of modern insects, so it is impossible to attribute them to any one genus now known to us. Undoubtedly, the Ordovician trilobites were the ancestors of the insects of the Carboniferous period. The Devonian and Silurian insects had much in common with some of their ancestors. They already played a significant role in the animal world.

Significant development in the Carboniferous period was received by lycopods, arthropods and ferns, which gave a large number of tree 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 scales - scars. Leaves were attached to them.

During this period, giant lycopods were common - lepidodendrons with rhombic scars on the trunks and sigillaria with hexagonal scars. Unlike most lycopods, sigillaria had 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, segmented, 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 carbonic flora, ferns played a prominent role, in particular herbaceous ones, but their structure resembled psilophytes, and real ferns - large tree-like plants, fixed in soft soil by rhizomes. 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 rather complex venation. 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 fruits developed from female sporangia. The results of microscopic examination of the fruits show that these plants, similar to cycads, were transitional forms to coniferous plants.
In the coal forests, the first mushrooms, moss plants (terrestrial and freshwater), sometimes forming colonies, and lichens appear. 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 feature coal flora - 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 the carboniferous flora is that the plants did not differ in rhythmic growth in thickness.

The spread of the same carboniferous plants from North America to Svalbard indicates that a relatively uniform warm climate dominated 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 growth of coal plants almost did not depend on the seasons. It resembled the growth of freshwater algae. The seasons probably did not differ much from each other.
When studying the "Carboniferous flora, one can trace the evolution of plants. Schematically, it looks like this: brown algae - psilophanty-pteridospermide ferns (seed ferns) - conifers.
When dying, the plants of the Carboniferous period fell into the water, they were covered with silt, and after lying for millions of years, they gradually turned into coal. Coal was formed from all parts of the plant: wood, bark, branches, leaves, fruits. The remains of animals were also turned into coal.

Carboniferous or Carboniferous period. It is the fifth period of an era. It lasted from 358 million years ago to 298 million years ago, that is, for 60 million years. In order not to get confused in eons, eras and periods, use the geochronological scale, which is located as a visual clue.

The name "Carboniferous" carbon was due to the fact that strong coal formation is found in the geological layers of this period. However, this period is characterized not only by increased coal formation. Carbon is also known for the formation of the supercontinent Pangea and the active development of life.

It was in the Carboniferous that the supercontinent Pangea appeared, which is considered the largest in size that has ever existed on Earth. Pangea was formed as a result of the union of the supercontinent Laurasia (North America and Eurasia) and the supercontinent Gondwana ( South America, Africa, Antarctica, Australia, New Zealand, Arabia, Madagascar and India). As a result of the connection, the old ocean, Rhea, ceased to exist, and a new ocean, Tethys, arose.

Flora and fauna underwent significant changes in the Carboniferous. The first coniferous trees, as well as cycads and cordaites. In the animal world, there was a rapid flowering and species diversity. This period can also be attributed to the flowering of land animals. The first dinosaurs appeared: primitive reptiles cotylosaurs, animal-like (synapsids or theromorphs, considered the ancestors of mammals), herbivorous edaphosaurs with a large crest on their backs. Many types of vertebrates appeared. In addition, insects flourished on land. Dragonflies, mayflies, flying cockroaches and other insects lived in the Carboniferous period. In the Carboniferous, several types of sharks are found at once, some of which reached 13 meters in length.

Animals of the Carboniferous

Arthropleura

Tuditanus punctulatus

Baphotides

Westlothiana

Cotylosaurus

Meganeura

Real size model of Meganeura

Nautiloids

Proterogyrinus

Edaphosaurus

Edaphosaurus

Eogyrinus

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The name of this period speaks for itself, since in this geological time period conditions were created for the formation of coal deposits 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 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) that 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 can withstand dry conditions better 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 fishes) at the end of the Devonian period, the Carboniferous is not well known for its existence, except when some genera of lobe-finned fishes 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, like plants, colonize every available . 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 bogs" near the equator, and millions of years later they formed the huge coal deposits that are used by mankind today.

Tsimbal Vladimir Anatolyevich is a lover and collector of plants. For many years he has been engaged in the morphology, physiology and history of plants, and has been conducting educational work.

In his book, the author invites us to an amazing and sometimes mysterious world plants. Accessible and simple, even for an unprepared reader, the book tells about the structure of plants, the laws of their life, the history of the plant world. In a fascinating, almost detective form, the author talks about many mysteries and hypotheses related to the study of plants, their origin and development.

The book contains a large number of drawings and photographs by the author and is intended for a wide range of readers.

All drawings and photographs in the book belong to the author.

The publication was prepared with the support of the Dmitry Zimin Dynasty Foundation.

The Dynasty Foundation for Non-Commercial Programs was founded in 2001 by Dmitry Borisovich Zimin, Honorary President of Vimpelcom. The priority areas of the Foundation's activities are support for fundamental science and education in Russia, popularization of science and education.

“Library of the Dynasty Foundation” is a project of the Foundation for the publication of modern popular science books selected by expert scientists. The book you are holding in your hands was published under the auspices of this project.

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On the cover - Ginkgo biloba (Ginkgo biloba) against the background of the imprint of a leaf of the probable ancestor of Ginkgo - Psygmophyllum expansum.

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The next period in the history of the Earth is the Carboniferous or, as it is often called, Carboniferous. One should not think that, for some magical reason, the change in the name of the period entails changes in the plant and animal world. No, the plant worlds of the Early Carboniferous and Late Devonian are not much different. Even in the Devonian, higher plants of all divisions, except for angiosperms, appeared. The Carboniferous period accounts for their further development and flourishing.

One of the important events that took place in the Carboniferous period was the emergence of different plant communities in different geographical areas. What does this mean?

At the beginning of the Carboniferous, it is difficult to find the difference between the plants of Europe, America, Asia. Unless there are some minor differences between the plants of the northern and southern hemispheres. But by the middle of the period, several areas with their own set of genera and species are clearly distinguished. Unfortunately, the opinion is still very widespread that the Carboniferous is the time of a universally warm humid climate, when the whole Earth was covered with forests of huge, up to 30 m high, lycopsform - lepidodendrons and sigillaria, and huge tree-like "horsetails" - calamites and ferns. All this luxurious vegetation grew in swamps, where, after death, it formed deposits hard coal. Well, to complete the picture, we must add giant dragonflies - meganevr and two-meter herbivorous centipedes.

It wasn't quite right. More precisely, it was not so everywhere. The fact is that in the Carboniferous, as now, the Earth was just as spherical and also rotated around its axis and revolved around the Sun. This means that even then on the Earth a zone of hot tropical climate passed along the equator, and it was cooler closer to the poles. Moreover, in the deposits of the end of the Carboniferous in the southern hemisphere, undoubted traces of very powerful glaciers were found. Why, even in textbooks, are we still told about the “warm and humid swamp”?

Such an idea of ​​the Carboniferous period was formed back in the 19th century, when paleontologists and, in particular, paleobotanists, only fossils from Europe were known. And Europe, like America, was in the tropics in the Carboniferous period. But to judge the plant and animal world only by one tropical belt, to put it mildly, is not entirely correct. Imagine that some paleobotanist after many millions of years, having dug up the remains of the current tundra vegetation, will make a report on the topic "The flora of the Earth of the Quaternary period." According to his report, it turns out that you and I, dear reader, live in extremely harsh conditions. That the whole Earth is covered by the extremely poor vegetable world, consisting mainly of lichens and mosses. Only in some places unfortunate people can stumble upon a dwarf birch and rare blueberry bushes. After describing such a bleak picture, our distant descendant will certainly conclude that a very cold climate prevailed on Earth everywhere, and decide that the reason for this is the low content of carbon dioxide in the atmosphere, low volcanic activity, or, on extreme case, in some regular meteorite that shifted the earth's axis.

Unfortunately, this is the usual approach to the climates and inhabitants of the distant past. Instead of trying to collect and study samples of fossil plants from different regions of the Earth, find out which of them grew at the same time, and analyze the data obtained, although, of course, this is difficult and requires a significant investment of effort and time, a person seeks to disseminate that knowledge , which he received by watching the growth of a room palm in the living room, for the entire history of plants.

But we still note that in the Carboniferous period, approximately at the end of the Early Carboniferous, scientists already distinguish at least three large areas with different vegetation. This region is tropical - Euramerian, northern extratropical - Angara region or Angarida and southern extratropical - Gondwana region or Gondwana. On the modern map of the world, Angarida is called Siberia, and Gondwana is the united Africa, South America, Antarctica, Australia and the Hindustan peninsula. The Euramerian region is, as the name implies, Europe together with North America. The vegetation of these areas varied greatly. So, if spore plants dominated in the Euramerian region, then in Gondwana and Angara, starting from the middle of the Carboniferous, gymnosperms dominated. Moreover, the difference in the floras of these areas increased during the entire Carboniferous and at the beginning of the Permian.

What other important events took place in the plant kingdom of the Carboniferous period? It is necessary to note the appearance of the first conifers in the middle of the Carboniferous. When we talk about coniferous plants, our familiar pines and spruces automatically come to mind. But coniferous carbons were a little different. These were, apparently, low, up to 10 meters, trees; By appearance they slightly resembled modern araucaria. The structure of their cones was different. These ancient conifers grew, probably in relatively dry places, and descended from ... it is not yet known what ancestors. Again, the point of view accepted by almost all scientists on this issue is as follows: conifers descended from cordaites. Kordaites, which appeared, apparently, at the beginning of the Carboniferous period, and also descended from no one knows who, are very interesting and peculiar plants (Fig. 8). These were trees with leathery, lanceolate leaves collected in bunches at the ends of the shoots, sometimes very large, up to a meter long. The reproductive organs of cordaites were long thirty-centimeter shoots with male or female cones sitting on them. It should be noted that the cordaites were very different. There were also tall slender trees, there were also inhabitants of shallow waters - plants with well-developed aerial roots, similar to the modern inhabitants of the mangroves. Among them were bushes.

In the Carboniferous, the first remains of cycads (or cycads) were also found - gymnosperms, not numerous today, but very common in the Mesozoic era following the Paleozoic.

As you can see, the future "conquerors" of the Earth - conifers, cycads, some pteridosperms existed for a long time under the canopy of coal forests and accumulated strength for a decisive offensive.

Of course, you noticed the name "seed ferns". What are these plants? After all, if there are seeds, then the plant cannot be a fern. That's right, the name is perhaps not very successful. After all, we don't call amphibians "fish with legs." But this name very well shows the confusion experienced by scientists who discovered and studied these plants.

This name was proposed at the beginning of the 20th century by the outstanding English paleobotanists F. Oliver and D. Scott, who, studying the remains of plants of the Carboniferous period, which were considered ferns, found that seeds were attached to leaves similar to the leaves of modern ferns. These seeds sat at the ends of the feathers or directly on the rachis of the leaf, as in the leaves of the genus Alethopteris(photo 22). Then it turned out that most of the plants of the coal forests, which were previously taken for ferns, are seed plants. It was a good lesson. Firstly, this meant that plants lived in the past that were completely different from modern ones, and secondly, scientists realized how deceptive they could be. external signs similarities. Oliver and Scott gave this group of plants the name "pteridosperms", which means "seed ferns". The names of the genera with the ending - pteris(in translation - a feather), which, according to tradition, were given to the leaves of ferns, remained. So the leaves of the gymnosperms got "fern" names: Alethopteris, Glossopteris and many others.

But worse was the fact that after the discovery of pteridosperms, all gymnosperms, not similar to modern ones, began to be attributed to seed ferns. Peltasperms, a group of plants with seeds attached to an umbrella-shaped disk - peltoid (from the Greek "peltos" - shield) on its lower side, and Caytoniums, in which the seeds were hidden in a closed capsule, and even glossopterids were also taken there. In general, if the plant was seed, but did not "climb" into any of existing groups, then it was immediately ranked among the pteridosperms. As a result, almost all the huge variety of ancient gymnosperms turned out to be united under one name - pteridosperms. If we follow this approach, then, without a doubt, it is necessary to attribute both modern ginkgo and cycads to seed ferns. Now seed ferns are considered by most paleobotanists to be a team, a formal group. However, the class Pteridospermopsida exists even now. But we will agree to call pteridosperms only gymnosperms with single seeds attached directly to a pinnately dissected fern-like leaf.

There is another group of gymnosperms that appeared in the Carboniferous - glossopterids. These plants covered the vastness of Gondwana. Their remains were found in deposits of the Middle and Late Carboniferous, as well as the Permian in all southern continents, including India, which was then in the southern hemisphere. We will talk about these peculiar plants in more detail a little later, since the time of their heyday is the Permian period following the Carboniferous.

The leaves of these plants (photo 24) were similar, at first glance, to the leaves of the Euramerian cordaites, although in the Angara species they are usually smaller and differ in microstructural features. But the reproductive organs are fundamentally different. In Angara plants, the organs that carried the seeds are more reminiscent of coniferous cones, although of a very peculiar kind that is not found today. Previously, these plants, voinovsky, were classified as cordaites. Now they are distinguished in a separate order, and in the recent publication “The Great Turning Point in the History of the Plant World” S. V. Naugolnykh even places them in a separate class. Thus, in the department of gymnosperms, along with the already listed classes, such as conifers or cycads, another one appears - Voynovskaya. These peculiar plants appeared at the end of the Carboniferous, but grew widely throughout almost the entire territory of Angara in the Permian period.

What else needs to be said about the Carboniferous period? Well, perhaps, the fact that he got his name for the reason that the main reserves of coal in Europe were formed at that time. But in other places, in particular, in Gondwana and Angarida, deposits of coal were formed, for the most part, in the next, Permian period.

Generally speaking, the flora of the Carboniferous period was very rich, interesting and varied and, for sure, deserves more detailed description. The landscapes of the Carboniferous period must have looked absolutely fantastic and unusual for us. Thanks to artists such as Z. Burian, who depicted the worlds of the past, we can now imagine the Carboniferous forests. But, knowing a little more about ancient plants and the climate of those times, we can imagine other, completely “alien” landscapes. For example, forests of small, two to three meters high, slender straight tree-like club mosses on a polar night, not far from the north pole of that time, in the current extreme northeast of our country.

Here is how S. V. Meyen describes this picture in his book “Traces of Indian Grass”: “A warm arctic night was coming. It was in this darkness that the thickets of lycopsids stood.

Strange landscape! It's hard to imagine it... Along the banks of rivers and lakes, a dull brush of sticks of various sizes stretches. Some collapsed. The water picks them up and carries them, knocks them down in heaps in the backwaters. In some places, the brush is interrupted by thickets of fern-like plants with rounded feather-leaves ... There probably hasn't been autumn leaf fall yet. Together with these plants, you will never meet either the bones of any quadruped, or the wing of an insect. It was quiet in the bushes."

But we still have a lot of interesting things ahead of us. Let's hurry on, to the last period of the Paleozoic era, or era ancient life, - in Perm.

In the Devonian, plants and animals were just beginning to explore the land, in the Carboniferous they mastered it. At the same time, an interesting transitional effect was observed - plants have already learned how to produce wood, but fungi and animals have not yet learned how to effectively consume it in real time. Because of this effect, a complex multi-stage process was initiated, as a result of which a significant part of the carbonic land turned into vast swampy plains, littered with undecayed trees, where coal and oil layers formed under the surface of the earth. Most of these minerals were formed in the Carboniferous period. Due to the massive removal of carbon from the biosphere, the oxygen content in the atmosphere has more than doubled - from 15% (in the Devonian) to 32.5% (now 20%). This is close to the limit for organic life - at high oxygen concentrations, antioxidants cease to cope with side effects oxygen respiration.

Wikipedia describes 170 genera related to the Carboniferous period. The dominant type, as before, is vertebrates (56% of all genera). The dominant class of vertebrates is still lobe-finned (41% of all genera), they can no longer be called lobe-finned fish, because the lion's share of lobe-finned fish (29% of all genera) acquired four limbs and ceased to be fish. The classification of carbon tetrapods is very cunning, confusing and contradictory. When describing it, it is difficult to use the usual words "class", "detachment" and "family" - small and similar friend on each other, the families of tetrapods of the Carboniferous gave rise to huge classes of dinosaurs, birds, mammals, etc. As a first approximation, carbon tetrapods are divided into two large groups and six small ones. We will consider them gradually, in descending order of diversity.

Other synapsids, varanopids, were more reminiscent of modern monitor lizards than lizards in their anatomical features. But they had nothing to do with monitor lizards, these are all tricks parallel evolution. In the Carboniferous, they were small (up to 50 cm).

The third group of synapsids of the Carboniferous are edaphosaurs. They became the first large herbivorous vertebrates, for the first time occupying the ecological niche of modern cows. Many edaphosaurs had a folding sail on their backs, which allowed them to more effectively regulate their body temperature (for example, to keep warm, you need to go out into the sun and open the sail). Edaphosaurus of the Carboniferous period reached 3.5 m in length, their weight reached 300 kg.

The last group of synapsids of the Carboniferous period worth mentioning are sphenacodonts. These were predators, for the first time in the history of tetrapods, powerful fangs grew at the corners of their jaws. Sphenacodonts are our distant ancestors, all mammals descended from them. Their sizes ranged from 60 cm to 3 m, they looked something like this:

On this topic, synapsids are revealed, let's consider other, less prosperous groups of reptiliomorphs. In second place (4% of all genera), anthracosaurs are the most primitive reptiliomorphs, possibly the ancestors of all other groups. They did not yet have a tympanic membrane in their ears, and in childhood they may have still passed the tadpole stage. Some anthracosaurs had a weakly pronounced tail fin. The sizes of anthracosaurs ranged from 60 cm to 4.6 m

The third large group of reptiliomorphs is sauropsids (2% of all genera of the Carboniferous). These were small (20-40 cm) lizards, already without quotes, in contrast to the lizard-like synapsids. Hylonomus (in the first picture) is the distant ancestor of all turtles, petrolacosaurus (in the second picture) is the distant ancestor of all other modern reptiles, as well as dinosaurs and birds.

To finally reveal the theme of reptiliomorphs, we mention strange creature Soledondosaurus (up to 60 cm), which is generally not clear which branch of the reptiliomorph it belongs to:

So, the topic of reptiliomorphs is revealed. Now let's move on to the second large group of tetrapods of the Carboniferous - amphibians (11% of all genera). Their largest subgroup was temnospondyls (6% of all genera of the Carboniferous). Previously, they, together with anthracosaurs, were called labyrinthodonts, later it turned out that the unusual structure of the teeth in anthracosaurs and temnospondyls formed independently. Temnospondyls are similar to modern newts and salamanders, the largest reaching a length of 2 m.

The second and last large group of amphibians of the Carboniferous are lepospondyls (thin vertebrae), they include 5% of all genera of the Carboniferous period. These creatures have completely or partially lost their limbs and have become similar to snakes. Their sizes ranged from 15 cm to 1 m.

So, all the large flourishing groups of tetrapods have already been considered. Let's take a brief look at small groups that almost do not differ from those described above, but are not closely related to them. These are transitional forms or dead-end branches of evolution. So let's go. Baphotids:

and other, very small groups:

On this topic, the tetrapods are finally revealed, let's move on to the fish. Cross-finned fishes (namely, fish, excluding tetrapods) make up 11% of all genera in the Carboniferous, while the layout is approximately as follows: 5% are tetrapodomorphs that did not go through the development of land, another 5% are coelacanths, and the remaining 1% are the miserable remnants of the Devonian diversity lungfish. In the Carboniferous, tetrapods displaced lungfish from almost all ecological niches.

In the seas and rivers, the lobe-finned fishes were strongly pressed by cartilaginous fishes. Now they are no longer a few births, as in the Devonian, but 14% of all births. The largest subclass of cartilaginous fishes is plastic gills (9% of all genera), the largest superorder of lamellar gills is sharks (6% of all genera). But these are not at all the sharks that swim in modern seas. The largest detachment of Carboniferous sharks are eugeneodonts (3% of all genera)

The most interesting feature of this detachment - a dental spiral - a long soft outgrowth on mandible, studded with teeth and usually coiled. Perhaps, during the hunt, this spiral was shot out of the mouth, like a "mother-in-law's tongue", and either grabbed the prey, or cut it like a saw. Or maybe it was meant for something else entirely. However, far from all eugeneodonts have a dental spiral in all its glory, some eugenodonts had dental arches (one or two) instead of a dental spiral, which are generally not clear why they are needed. A typical example is edestus

Eugeneodonts were large fish - from 1 to 13 m,Campodusbecame the largest animal of all time, breaking the Devonian record of the dunkleosteus.

However, the helocoprion was only a meter shorter

The second large detachment of Carboniferous sharks are symmoriids (2% of all genera). This includes the stethacant, already familiar to us from the Devonian survey. Symmoriids were relatively small sharks, no more than 2 m in length.

The third order of Carboniferous sharks, worthy of mention, is xenacanthids. These were moderately large predators, from 1 to 3 m:

An example of a Late Carboniferous xenocanthus is at least a pleuracanthus, one of the most studied representatives of ancient sharks. These sharks were found in fresh waters Australia, Europe and North America, complete remains unearthed in the mountains near the city of Pilsen. Despite the relatively small size- 45-200 cm, usually 75 cm - pleuracanths were formidable enemies for acanthodia and other small fish of that time. Attacking a fish, the pleuracanth instantly destroyed it with its teeth, each of which had two divergent points. Moreover, they hunted, as it is believed, in packs. According to the assumptions of scientists, pleuracanths laid their eggs, connected by a membrane, in the shallow and sunny corners of small reservoirs. Moreover, both freshwater and brackish water reservoirs. Pleuracanths were also found in the Permian - their numerous remains were found in the Permian strata of the Central and Western

pleuracanthus

Europe. Then pleuracanths had to coexist with many other sharks adapted to the same habitat conditions.

It is impossible to ignore one of the most remarkable ktenokant sharks, which is also the property of the Carboniferous. I mean banding. The body of this shark did not exceed 40 cm in length, but almost half of it was occupied by ... a snout, a rostrum! The purpose of such an amazing invention of nature is not clear. Maybe the bandrings felt the bottom with the tip of their snouts in search of food? Maybe, like on a kiwi's beak, the nostrils were located at the end of the shark's rostrum and helped it to sniff everything around, since they had poor eyesight? So far, no one knows. Bandringa's occipital spine was not found, but most likely she had one. Amazing long-nosed sharks lived both in fresh waters and in salty ones.

The last Ctenocantans died out in the Triassic period.

On this topic, carbon sharks are fully disclosed. Let's mention a few more lamella-gill fish, similar to sharks, but not being them, these are tricks of parallel evolution. These “pseudo-sharks” include 2% of all genera of the Carboniferous, they were mainly small fish - up to 60 cm.

Now let's move on from laminabranchs to the second and last large subclass of cartilaginous fish - whole-headed (5% of all genera of the Carboniferous). These are small fish, similar to modern chimeras, but more diverse. Chimeras also belong to the whole-headed and already existed in the Carboniferous.

On this topic, cartilaginous fish are completely exhausted. Let's take a quick look at the two remaining classes of fish from the Carboniferous: ray-finned fish (7-18 cm):

and acanthode (up to 30 cm):

Both of these classes vegetated quietly in the Carboniferous. As for the armored fishes and almost all jawless fishes, they became extinct at the end of the Devonian, and thus the review of the fishes of the Carboniferous period is completed. Let us briefly mention that in the Carboniferous primitive chordates and hemi-chordates, which did not have a real spine, were found here and there, and we will move on to the next large phylum of Carboniferous animals - arthropods (17% of all genera).

The main news in the world of arthropods is that on the transition from the Devonian to the Carboniferous, trilobites almost died out, only a small detachment remained of them, which continued a miserable existence until the next big extinction at the end of the Permian period. The second big news was the appearance of insects (6% of all genera). The abundance of oxygen in the air allowed these creatures not to form a normal respiratory system, and use poor tracheae and feel no worse than other terrestrial arthropods. Contrary to popular belief, the diversity of insects in the Carboniferous period was small, most of them were very primitive. The only extensive detachment of Carboniferous insects is dragonflies, the largest of which (meganeura, shown in the picture) reached a wingspan of 75 cm, and approximately corresponded in mass to a modern crow. However, most Carboniferous dragonflies were much smaller.