The first land plants. The evolution of the organic world in the Proterozoic and Paleozoic eras When 1 plants appeared

First land plants and animals

WHERE LIFE ORIGINATED Life originated in water. Here the first plants appeared - algae. However, at some point, land appeared, which had to be populated. Pioneers among animals were lobe-finned fish. And among plants?

WHAT THE FIRST PLANTS LOOKED LIKE Once upon a time, our planet was inhabited by plants that had only a stem. They were attached to the ground with special outgrowths - rhizoids. These were the first plants to reach land. Scientists call them psilophytes. This is a Latin word. Translated, it means "naked plants". The psilophytes really looked "naked". They had only branching stems with outgrowths of balls in which spores were stored. They are very similar to the "alien plants" that are depicted in illustrations for fantastic stories. Psilophytes became the first land plants, but they lived only in swampy areas, since they did not have a root, and they could not extract water and nutrients in the soil. Scientists believe that once these plants created huge carpets over the bare surface of the planet. There were both tiny plants and very large ones, taller than human growth.

THE FIRST ANIMALS ON EARTH The oldest traces of animal life on Earth date back a billion years, but the oldest fossils of the animals themselves are approximately 600 million years old and date back to the Vendian period. The first animals that appeared on Earth as a result of evolution were microscopically small and soft-bodied. They lived on the seabed or in bottom silt. Such creatures could hardly be petrified, and the only clue to the mystery of their existence is indirect traces, such as the remains of burrows or passages. But despite their tiny size, these most ancient animals were resilient and gave rise to the first known animals on Earth - the Ediacaran fauna.

The evolution of life on Earth began with the appearance of the first living being - about 3.7 billion years ago - and continues to this day. The similarity between all organisms indicates the presence of a common ancestor from which all other living beings descended.

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psilophyta (Psilophyta), the most ancient and primitive extinct group (department) of higher plants. They were characterized by the apical arrangement of sporangia and equispores, the absence of roots and leaves, dichotomous or dichopodial (pseudomonopodial) branching, and a primitive anatomical structure. The conducting system is a typical Protostele. The protoxylem was located in the center of the xylem; the metaxylem consisted of tracheids with annular or (rarely) scalariform thickenings. Support tissues were absent. R. did not yet possess the ability for secondary growth (they had only apical meristems). Sporangia are primitive, from spherical (about 1 mm in diameter) to oblong-cylindrical (up to 12 mm long), thick-walled. R.'s gametophytes are not reliably known (some authors consider horizontal rhizome-like organs, the so-called rhizomoids, to be gametophytes).

R. grew in wet and swampy places, as well as in shallow coastal waters. R.'s department includes one class - rhyniopsida (Rhyniopsida) with two orders - Rhyniales (families Cooksoniaceae, Rhyniaceae, Hedeiaceae) and Psilophytales (family Psilophytaceae). The order Rhyniales is characterized by dichotomous branching and a thin, poorly developed stele. Xylem of tracheids with ringed thickenings. The oldest representative of R. is the genus Cooksonia, originally discovered in Wales in the deposits of the end of the Silurian period (about 400 million years ago). The most fully studied are the Lower Devonian genera - rhynia and partly horneophyte, in which the rhizomoid (stems departed from it upwards, numerous Rhizoids downwards) was divided into clearly arranged tuberous segments, devoid of conductive tissues and consisted entirely of parenchymal cells. It is believed that in the course of evolution R.'s rhizomoids gave rise to roots. In both genera, the sporangium wall was multi-layered, covered with a cuticle (See Cuticle). The horneophyte is characterized by a peculiar spore-bearing cavity, which forms a dome that arch-like covers the central column of sterile tissue, which is a continuation of the stem phloem. This horneophyte resembles modern Sphagnum. Rhynia families also include the genus teniokrada, many species of which formed underwater thickets in the Middle and Upper Devonian. The Lower Devonian genera Khedea and Yaravia are sometimes distinguished into a separate family of Hedei. The Lower Devonian genus Sciadophyte, usually classified as a separate family of Sciadophytes, is a small plant consisting of a rosette of simple or weakly dichotomized thin stems with a stele. The order Psilophytales is characterized by dichopodial branching and a more strongly developed stele. In the most famous genus, psilophyte (from Lower Devonian deposits in Eastern Canada), unequally developed branches formed a false main axis of dichopodium with thinner side branches: the stem was surrounded by a cutinized epidermis with stomata; the surface of the stem was bare or covered with spines 2–2.5 mm long, the ends of which widened disc-like, which probably indicated their secretory role. The sporangia opened with a longitudinal fissure. The Lower Devonian genera Trimerophyte and Pertika are close to psilophyte.

The study of the structure of R. and their evolutionary relationships is of great importance for the evolutionary morphology and phylogeny of higher plants. Apparently, the original organ of the Sporophyte of higher plants was a dichotomously branching stem with apical sporangia; roots and leaves are later than sporangium and stem. There is every reason to consider R. the original ancestral group from which bryophytes, lycopsids, horsetails, and ferns originated. According to another point of view, bryophytes and lycopsids have only a common origin with P.

Lit .: Fundamentals of paleontology. Algae, bryophytes, psilophytes, lycopsids, arthropods, ferns, M., 1963; Traite de paleobotanique, t. 2, Bryophyta. psilophyta. Lycophyta, P., 1967.

A. L. Takhtadzhyan.

Planet Earth was formed over 4.5 billion years ago. The first single-celled life forms appeared, possibly about 3 billion years ago. First it was bacteria. They are classified as prokaryotes because they do not have a cell nucleus. Eukaryotic (with nuclei in the cells) organisms appeared later.

Plants are eukaryotes capable of photosynthesis. In the process of evolution, photosynthesis appeared earlier than eukaryotes. At that time it existed in some bacteria. These were blue-green bacteria (cyanobacteria). Some of them have survived to this day.

According to the most common hypothesis of evolution, the plant cell was formed by entering a heterotrophic eukaryotic cell of a photosynthetic bacterium that was not digested. Further, the process of evolution led to the emergence of a single-celled eukaryotic photosynthetic organism with chloroplasts (their predecessors). This is how unicellular algae appeared.

The next stage in the evolution of plants was the emergence of multicellular algae. They reached a great diversity and lived exclusively in the water.

The surface of the earth did not remain unchanged. Where the earth's crust was rising, land gradually arose. Living organisms had to adapt to new conditions. Some ancient algae were gradually able to adapt to the terrestrial way of life. In the process of evolution, their structure became more complicated, tissues appeared, primarily integumentary and conductive.

The psilophytes, which appeared about 400 million years ago, are considered the first land plants. They have not survived to this day.

Further evolution of plants, associated with the complication of their structure, was already on land.

During the time of the psilophytes, the climate was warm and humid. Psilophytes grew near water bodies. They had rhizoids (like roots), with which they were fixed in the soil and absorbed water. However, they did not have true vegetative organs (roots, stems, and leaves). The movement of water and organic substances through the plant was ensured by the emerging conductive tissue.

Later, ferns and mosses originated from psilophytes. These plants have a more complex structure, they have stems and leaves, they are better adapted to living on land. However, just like the psilophytes, they remained dependent on water. During sexual reproduction, in order for the sperm to reach the egg, they need water. Therefore, they could not "go" far from wet habitats.

In the Carboniferous period (about 300 million years ago), when the climate was humid, ferns reached their dawn, many of their woody forms grew on the planet. Later, dying off, it was they who formed deposits of coal.

When the climate on Earth began to become colder and drier, ferns began to die out en masse. But some of their species before that gave rise to the so-called seed ferns, which, in fact, were already gymnosperms. In the subsequent evolution of plants, seed ferns died out, giving rise to other gymnosperms before this. Later, more advanced gymnosperms appeared - conifers.

The first plants on earth

Pollination took place with the help of wind. Instead of spermatozoa (mobile forms), they formed sperm (immobile forms), which were delivered to the egg by special formations of pollen grains. In addition, gymnosperms did not form spores, but seeds containing a supply of nutrients.

The further evolution of plants was marked by the appearance of angiosperms (flowering). This happened about 130 million years ago. And about 60 million years ago they began to dominate the Earth. Compared to gymnosperms, flowering plants are better adapted to life on land. It can be said that they began to use the possibilities of the environment more. So their pollination began to occur not only with the help of wind, but also through insects. This increased the efficiency of pollination. Seeds of angiosperms are found in fruits, which provide more efficient distribution. In addition, flowering plants have a more complex tissue structure, for example, in the conducting system.

Currently, angiosperms are the most numerous group of plants in terms of the number of species.

Main article: Ferns

Rhyniophytes is an extinct group of plants. Some scientists consider them to be the ancestors of mosses, ferns, horsetails and club mosses. Others suggest that rhinophytes mastered the land at the same time as mosses.

The first land plants - rhinophytes appeared about 400 million years ago. Their body consisted of green twigs. Each branch branched, dividing into two parts. The vein cells contained chlorophyll and photosynthesis took place. Material from the site http://wikiwhat.ru

Rhinophytes grew in moist places. They were attached to the soil by rhizoids - outgrowths on the surface of horizontally located veto-checks.

The first land plants

At the ends of the branches were spore-bearing parts, in which spores ripened. In rhinophytes, conductive and mechanical tissues have already begun to form. In the process of evolution, due to the occurrence of hereditary changes and natural selection, an integumentary tissue with stomata regulating the evaporation of water was formed on the surface of rhinophyte branches.

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On this page, material on the topics:

• Conductive integumentary and mechanical tissues in rhinophyte and ferns

• Life cycle of rionophytes diagram

• The story of rhinophyta answer

• Message first land plant

• When and from what group of algae did the first reniophytes appear?

Origin and systematics of higher plants.

Higher plants probably evolved from some kind of algae. This is evidenced by the fact that in the geological history of the plant world, higher plants were preceded by algae. The following facts testify in favor of this assumption: the similarity of the most ancient extinct group of higher plants - rhinophytes - with algae, a very similar nature of their branching; similarity in the alternation of generations of higher plants and many algae; the presence of flagella and the ability to swim independently in the male germ cells of many higher plants; similarity in structure and function of chloroplasts.

It is believed that higher plants evolved from green algae, freshwater or brackish water. They had multicellular gametangia, isomorphic alternation of generations in the development cycle.

The first land plants found in the fossil state were rhinophytes(rhinia, hornea, horneophyton, sporogonites, psilophyte, etc.).

After reaching land, higher plants developed in two main directions and formed two large evolutionary branches - haploid and diploid.

The haploid branch of the evolution of higher plants is represented by the bryophyte division (Bryophyta). In the development cycle of mosses, the gametophyte, the sexual generation (the plant itself), predominates, while the sporophyte, the asexual generation, is reduced and is represented by a sporogon in the form of a box on a leg.

The second evolutionary branch of higher plants is represented by all other higher plants.

The sporophyte under terrestrial conditions turned out to be more viable and adapted to various environmental conditions. This group of plants conquered land more successfully.

Currently, higher plants number over 300,000 species. They dominate the Earth, inhabit it from the Arctic territories to the equator, from the humid tropics to dry deserts. They form various types of vegetation - forests, meadows, swamps, fill reservoirs. Many of them reach gigantic proportions.

Taxonomy of higher plants- This is a branch of botany that develops a natural classification of higher plants based on the study and selection of taxonomic units, establishes family ties between them in their historical development. The most important concepts of taxonomy are taxonomic (systematic) categories and taxa.

plant evolution

According to the rules of botanical nomenclature, the main taxonomic categories are: species (species), genus (genus), family (familia), order (ordo), class (classis), department (devisio), kingdom (regnum). If necessary, intermediate categories can also be used, for example, subspecies (subspecies), genus (subgenus), subfamily (subfamilia), superorder (superordo), superregnum (superregnum).

For species starting from 1753 - the date of publication of the book K. Linnaeus"Plant species" - accepted binominal names, consisting of two Latin words. The first designates the genus to which the given species belongs, the second - the specific epithet: for example, sticky alder - Alnus glutinosa.

For plant families, the ending is aceae, for orders - ales, for subclasses - idae, for classes - psida, for divisions - phyta. The standard uninominal name is based on the name of any genus included in this family, order, class, etc.

Modern science of the organic world divides living organisms into two kingdoms: pre-nuclear organisms (Procariota) and nuclear organisms (Eucariota). The supra-kingdom of pre-nuclear organisms is represented by one kingdom - shotguns (Mychota) with two sub-kingdoms: bacteria (Bacteriobionta) and cyanothea, or blue-green algae (Cyanobionta).

The superkingdom of nuclear organisms includes three kingdoms: animals (Animalia), fungi (Mycetalia, Fungi, or Mycota) and plants (Vegetabilia, or Plantae).

The animal kingdom is divided into two sub-kingdoms: protozoa and multicellular animals (Metazoa).

The kingdom of fungi is divided into two sub-kingdoms: lower fungi (Myxobionta) and higher fungi (Mycobionta).

The plant kingdom includes three sub-kingdoms: scarlet(Rhodobionta), real algae(Phycobionta) and higher plants(Embryobionta).

Question 1. When did the first land plants appear?
At the beginning of the Paleozoic era, plants inhabited mainly the seas, but in the Ordovician - Silurian, the first terrestrial plants appeared - psilophytes (Fig. 1).

Rice. 1. The first land plant

They were small plants intermediate between algae and terrestrial vascular plants. Psilophytes already had a conducting (vascular) system, the first weakly differentiated tissues could become stronger in the soil, although the roots (like other vegetative organs) were still absent. The further evolution of plants on land was aimed at the differentiation of the body into vegetative organs and tissues, and the improvement of the vascular system (ensuring the rapid rise of water to a great height).

Question 2. In what direction was the evolution of plants on land?
After the appearance of psilophytes, the evolution of plants on land went in the direction of dividing the body into vegetative organs and tissues, improving the vascular system (ensuring the rapid movement of water to a great height). Already in the arid Devonian, horsetails, club mosses, and ferns are widely distributed. Ground vegetation reaches even greater development in the Carboniferous period (Carboniferous), characterized by a humid and warm climate throughout the year. Gymnosperms appear, descended from seed ferns. The transition to seed reproduction gave many advantages: the embryo in seeds is protected from unfavorable conditions by membranes and provided with food, and has a diploid number of chromosomes. In some gymnosperms (conifers), the process of sexual reproduction is no longer associated with water. Pollination in gymnosperms is carried out by the wind, and the seeds have adaptations for distribution by animals. These and other advantages contributed to the widespread distribution of seed plants. Large spore plants die out in the Permian due to the drying up of the climate.

Question 3. Describe the evolution of animals in the Paleozoic era.
The animal world in the Paleozoic era developed extremely rapidly and was represented by a large number of diverse forms. Life flourishes in the seas. In the Cambrian period, all the main types of animals already exist, except for chordates. Sponges, corals, echinoderms, various molluscs, huge predatory crustaceans - this is an incomplete list of the inhabitants of the Cambrian seas.
In the Ordovician, the improvement and specialization of the main types continues. For the first time, the remains of animals with an internal axial skeleton are found - jawless vertebrates, the distant descendants of which are modern lampreys and hagfishes. The mouth of these peculiar organisms was a simple opening leading to the digestive tract. The anterior part of the digestive tube was pierced by gill slits, between which were located supporting cartilaginous gill arches. Jawless ate organisms living in the muddy bottom of rivers and lakes, and detritus (organic residues), sucking food in their mouths. In a part of jawless animals, the division of the gill arches occurred, which made it possible to change the lumen of the pharynx with the help of the gill muscles and, consequently, to keep the mobile prey that got into the digestive tube.
The appearance of a grasping mouth apparatus - a large aromorphosis - caused a restructuring of the entire organization of vertebrates.
The emergence of paired fins - limbs - is the next major aromorphosis in the evolution of vertebrates.
In the Silurian period, the first air-breathing animals - arthropods - came to land along with psilophytes. The intensive development of lower vertebrates continued in water bodies. It is assumed that vertebrates arose in shallow freshwater reservoirs and only then moved to the seas. The Devonian period was marked by the development of land by other arthropods - spiders; at the end of the period, the first terrestrial vertebrates appear - amphibians (stegocephals). In the Carboniferous, reptiles (cotylosaurs), flying insects, and lung molluscs arose. In the last, Permian period of the Paleozoic era, a rapid development and increase in systematic groups of reptiles is observed; animal-toothed reptiles appear - the ancestors of mammals.

Question 4. What features of the structure of vertebrates served as prerequisites for their release on land?
In the Silurian period, the first air-breathing animals - arthropods - came to land along with psilophytes. The intensive development of lower vertebrates continued in water bodies. It is assumed that vertebrates arose in shallow freshwater reservoirs and only then moved to the seas. In the Devonian, vertebrates are represented by three groups: lungfish, ray-finned fish, and lobe-finned fish. It was the lobe-finned fish that gave rise to terrestrial vertebrates. The lobe-finned fish were typically aquatic animals, but they could breathe atmospheric air with the help of primitive lungs, which were protrusions of the intestinal wall. Only lobe-finned fish could adapt to life on land. Their fins were blades consisting of individual bones with muscles attached to them (Fig. 2). With the help of fins, lobe-finned fish - large animals from 1.5 to several meters long - could crawl along the bottom. Thus, they had two main prerequisites for the transition to the terrestrial habitat: muscular limbs and lungs. At the end of the Devonian, lobe-finned fish gave rise to the first amphibians - stegocephals.

Rice. 2. Skeleton of the paired fin of a lobe-finned fish and a stegocephalus:
A - shoulder girdle and fin of a lobe-finned fish;
B - internal skeleton of the fin;
B - skeleton of the forelimb of a stegocephalus:
1 - element corresponding to the humerus;
2 - element corresponding to the radius;
8 - element corresponding to the ulna;
4, 5, 6 - bones of the wrist; 7 - phalanges of fingers.

In this article we will discuss an important and interesting topic - the emergence and development of the plant world on the planet. Today, walking in the park during the flowering of lilacs, picking mushrooms in the autumn forest, watering home flowers on the windowsill, insisting on a decoction of chamomile during an illness, we rarely think about how the Earth looked before the advent of plants. What was the landscape like at the time when single-celled plants were just emerging or the first weak land plants appeared? What did forests look like in the Paleozoic and Mesozoic? Imagine that the ancestors of those half-meter ferns, which now modestly hide in the shade of fir trees, reached a height of 30 meters or more 300 million years ago!

Let's list the main stages of the emergence of the living world.

The origin of life

1. 3, 7 billion years ago arose first living organisms. The time of their appearance (very approximately, with a "fork" of hundreds of millions of years) today can be assumed from the deposits formed by them. For a million plus years cyanobacteria have learned oxygen photosynthesis and so bred that they became the culprits of the oversaturation of the atmosphere with oxygen about 2.4 billion years ago - this led to the extinction of anaerobic organisms, for which oxygen was a poison. The living world of the Earth has changed radically!

2. 2 billionyears ago there were already different unicellular both autotrophs and heterotrophs. These p first unicellular did not have nuclei and plastids - the so-called heterotrophic prokaryotes (bacteria). It was they who gavethe impetus for the appearance of the first unicellular plants.

3. 1, 8 billionyears ago, nuclear unicellular organisms arose,that is, eukaryotes, soon (by geological standards)typical animal and plant cells appeared.

The emergence of multicellular plants

1. Near 1, 2 billion years back on the basis of unicellular originatedmulticellular algae.

2. At that time, life existed only in warm seas and oceans, but living organisms actively developed and progressed - they were preparing for the development of land.

Exit of plants to land

1. 4 20 millionyears ago, the first land plants appeared - mosses and psilophytes (rhinophytes). They originated in many places on the planet.independently of each other, from different multicellular algae.Of course, at first they mastered only the coastal edge.

2. psilophytes(For example, riniya) lived along the banks, in shallow water, like modern m sedges. These were small weak plants, whose life was complicated by the lack of shoots and roots.. Instead of roots that can properly cling to the soil, psilophytes had rhizoids. The upper part of the psilophyte contained a green pigment and was capable of photosynthesis. These pioneers, bold invaders of land, have died out,but were able to give rise to ferns.

4. mosses - for all their unusualness, beauty and ubiquity in our days - have become a dead end branch of evolution. Having arisen hundreds of millions of years ago, they could not give rise to any other groups of plants.

Our planet has not always been green. A long time ago, when life was just emerging, the land was empty and lifeless - the first forms chose the oceans as their habitat. But gradually the earth's surface also began to be mastered by various creatures. The first plants on Earth are also the earliest inhabitants of land. What were the ancestors of modern representatives of the flora?

So, imagine the Earth 420 million years ago, in an era called the Silurian period. This date was not chosen by chance - it was at this time, scientists believe, that plants finally began to conquer the land.

For the first time, the remains of cooksonia were discovered in Scotland (the first representative of the terrestrial flora was named after Isabella Cookson, a famous paleobotanist). But scientists suggest that it was distributed throughout the globe.

It was not so easy to get out of the waters of the oceans and start developing the land. To do this, the plants had to literally rebuild the entire body: to acquire a shell resembling a cuticle that prevents drying out, and to acquire special stomata, with which it was possible to regulate evaporation and absorb the substances necessary for life.

Cooksonia, which is a thin green stems, not exceeding five centimeters in height, was considered one of the most developed plants. But the atmosphere of the Earth and its inhabitants were rapidly changing, and the most ancient representative of the flora was losing ground more and more. At the moment, the plant is considered extinct.

The remains of the nematothallus do not even remotely resemble plants - they look more like shapeless black spots. But despite the strange appearance, in terms of development, this plant has gone far ahead of its comrades in its habitat. The fact is that the cuticle of the nematothallus is already more similar to the parts of existing plants - it consisted of formations resembling modern cells, which is why it was called pseudocellular. It should be noted that in other species this shell looked just like a continuous film.

Nematothallus has given a lot of food for thought to the scientific world. Some scientists attributed it to red algae, others were inclined to believe that they had a lichen in front of them. And until now, the mystery of this ancient organism has not been solved.

Rinia and almost all other ancient plants with a vascular structure are classified as rhinophytes. Representatives of this group have not grown on Earth for a long time. However, this fact does not at all prevent scientists from studying these living creatures that once dominated the land - a lot of fossils found in many parts of the world make it possible to judge both the appearance and the structure of such plants.

Rhiniophytes have several important features that allow us to assert that these living creatures are completely different from their descendants. First, their stem was not covered with soft bark: scaly processes grew on it. Secondly, rhinophytes reproduced exclusively with the help of spores, which were formed in special organs called sporangia.

But the most important difference is that these plants did not have a root system as such. Instead, there were root formations covered with "hairs" - rhizoids, with the help of which rhinia absorbed water and substances necessary for life.

This plant was recently considered a representative of the animal world. The fact is that its remains - small, rounded in shape - were originally mistaken for eggs of frogs or fish, algae, or even eggs of long-extinct crustacean scorpions. The spores of the parka, found in 1891, put an end to the misconceptions.

The plant lived on our planet about 400 million years ago. This time refers to the beginning of the Devonian period.

Pachiteki remains, as well as the parka fossils found, are small balls (the largest of those discovered has a diameter of 7 millimeters). Quite little is known about this plant: scientists managed to establish only the fact that it consisted of tubules located radially and converging in the center where the nucleus was located.

This plant is a dead end branch of the development of flora, in fact, like parks and rhinia. It was not possible to establish for certain what was the impetus for their emergence, and why they died out. The only reason, according to scientists, is the development of vascular plants, which simply replaced their less developed relatives.

The plants that got out on land chose a completely different path of development. It was thanks to them that the animal world was born and, accordingly, a reasonable form of life appeared - man. And who knows what our planet would look like now if the rhinii, parkas and cooksonia had not decided to explore the land? ..

That's all we have. We are very glad that you have looked at our site and spent some time enriching yourself with new knowledge.

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400 million years ago, a huge part of the earth's surface of our planet was occupied by seas and oceans. The first living organisms arose in the aquatic environment. They were pieces of slime. After several million years, these primitive microorganisms developed a green color. In appearance, they began to resemble algae.

Plants in the Carboniferous

Climatic conditions favorably influenced the growth and reproduction of algae. Over time, the surface of the earth and the bottom of the oceans were subjected to changes. New continents arose, while the old ones disappeared under water. The earth's crust was actively changing. These processes led to the fact that water appeared on the site of the earth's surface.

Retreating, sea water fell into crevices, depressions. They then dried up, then again filled with water. As a result, those algae that were on the seabed gradually moved to the earth's surface. But since the drying process was very slow, during this time they adapted to the new living conditions on earth. This process has been going on for millions of years.

The climate at that time was very humid and warm. He contributed to the transition of plants from marine to terrestrial life. Evolution led to the complication of the structure of various plants, and ancient algae also changed. They gave rise to the development of new terrestrial plants - psilophytes. In appearance, they resembled small plants that were located near the banks of river lakes. They had a stem that was covered with small bristles. But, like algae, psilophytes did not have a root system.

Plants in a new climate

Ferns originated from psilophytes. The psilophytes themselves ceased to exist 300 million years ago.

Humid climate and a large amount of water led to the rapid spread of various plants - ferns, horsetails, club mosses. The end of the Carboniferous period was marked by a change in climate: it became drier and colder. Huge ferns began to die out. The remains of dead plants rotted and turned into coal, with which people then heated their homes.

Ferns had seeds on their leaves, which were called gymnosperms. Modern pines, spruces, firs, which are called gymnosperms, originated from giant ferns.

With climate change, ancient ferns have disappeared. The cold climate destroyed their tender shoots. They were replaced by seed ferns, which are called the first gymnosperms. These plants have perfectly adapted to the new conditions of a dry and cold climate. In this plant species, the reproduction process did not depend on the water that is in the external environment.

130 million years ago, various shrubs and herbs arose on Earth, the seeds of which were in the surface of the fruit. They were called angiosperms. For 60 million years, angiosperms have lived on our planet. These plants have remained virtually unchanged from then to the present day.