The main stages of the evolution of flora and fauna. Evolution of plants. Stages of evolution of the plant world Correct sequence of appearance of the main groups of plants
STAGES OF EARLY EVOLUTION:
Coacervates (emergence of precellular life forms)
Prokaryotic cells (the emergence of life, cellular life forms - anaerobic heterotrophs)
Chemosynthetic bacteria (emergence of chemosynthesis)
Photosynthetic bacteria (the appearance of photosynthesis, in the future this will lead to the emergence of an ozone screen, which will allow organisms to reach land)
Aerobic bacteria (the appearance of oxygen respiration)
Eukaryotic cells (emergence of eukaryotes)
Multicellular organisms
- (exit of organisms to land)
STAGES OF PLANT EVOLUTION:
- (the appearance of photosynthesis in prokaryotes)
Unicellular algae
Multicellular algae
Rhiniophytes, Psilophytes (plant emergence onto land, cell differentiation and appearance of tissues)
Mosses (appearance of leaves and stem)
Ferns, Horsetails, Mosses (appearance of roots)
Angiosperms (appearance of flower and fruit)
STAGES OF ANIMALS EVOLUTION:
Protozoa
Coelenterates (appearance of multicellularity)
Flatworms (the emergence of bilateral symmetry)
Roundworms
Annelids(dividing the body into segments)
Arthropods (the appearance of chitinous cover)
Cranials (formation of notochord, ancestors of vertebrates)
Fish (emergence of the brain in vertebrates)
Lobe-finned fish
Stegocephals (transitional forms between fish and amphibians)
Amphibians (the emergence of lungs and five-fingered limbs)
Reptiles
Oviparous mammals (the emergence of a four-chambered heart)
Placental mammals
ADDITIONAL INFORMATION:
PART 2 ASSIGNMENTS:
Tasks
Establish the sequence of stages characterizing the evolution of the process of reproduction of living organisms. Write down the corresponding sequence of numbers.
1) viviparity in mammals
2) the emergence of simple binary fission of bacteria
3) external fertilization
4) internal fertilization
5) the emergence of conjugation of unicellular
Answer
COACERVATES
1. Establish the sequence of evolutionary processes on Earth in chronological order
1) the emergence of organisms onto land
2) the emergence of photosynthesis
3) formation of an ozone screen
4) formation of coacervates in water
5) the emergence of cellular life forms
Answer
2. Establish the sequence of evolutionary processes on Earth in chronological order
1) the emergence of prokaryotic cells
2) formation of coacervates in water
3) the emergence of eukaryotic cells
4) emergence of organisms onto land
5) the emergence of multicellular organisms
Answer
3. Establish the sequence of processes occurring during the origin of life on Earth. Write down the corresponding sequence of numbers.
1) the appearance of a prokaryotic cell
2) formation of the first closed membranes
3) synthesis of biopolymers from monomers
4) formation of coacervates
5) abiogenic synthesis of organic compounds
Answer
HETEROTROPHES-AUTOTROPHES-EUKARYOTES
1. Establish a sequence reflecting the stages of evolution of protobionts. Write down the corresponding sequence of numbers.
1) anaerobic heterotrophs
2) aerobes
3) multicellular organisms
4) unicellular eukaryotes
5) phototrophs
6) chemotrophs
Answer
2. Establish the sequence of occurrence of groups of organisms in evolution organic world Earths in chronological order. Write down the corresponding sequence of numbers.
1) heterotrophic prokaryotes
2) multicellular organisms
3) aerobic organisms
4) phototrophic organisms
Answer
3. Establish the sequence of biological phenomena that occurred in the evolution of the organic world on Earth. Write down the corresponding sequence of numbers.
1) the appearance of aerobic heterotrophic bacteria
2) the emergence of heterotrophic probionts
3) the emergence of photosynthetic anaerobic prokaryotes
4) formation of eukaryotic unicellular organisms
Answer
PLANTS SYSTEM UNITS
1. Establish the chronological sequence in which the main groups of plants appeared on Earth
1) green algae
2) horsetails
3) seed ferns
4) rhiniophytes
5) gymnosperms
Answer
2. Establish the chronological sequence in which the main groups of plants appeared on Earth
1) Psilophytes
2) Gymnosperms
3) Seed ferns
4) Unicellular algae
5) Multicellular algae
Answer
3. Establish the sequence of systematic position of plants, starting with the smallest category. Write down the corresponding sequence of numbers.
1) psilophytes
2) unicellular algae
3) multicellular algae
4) gymnosperms
5) fern-like
6) angiosperms
Answer
Arrange the plants in a sequence that reflects the increasing complexity of their organization during the evolution of the systematic groups to which they belong.
1) Chlamydomonas
2) Psilofite
3) Scots pine
4) Bracken fern
5) Chamomile
6) Kelp
Answer
AROMORPHOSIS PLANTS
1. Establish the sequence of aromorphoses in the evolution of plants, which determined the appearance of more highly organized forms
1) cell differentiation and tissue appearance
2) appearance of the seed
3) formation of flower and fruit
4) the appearance of photosynthesis
5) formation of the root system and leaves
Answer
2. Establish the correct sequence of occurrence of the most important aromorphoses in plants. Write down the corresponding sequence of numbers.
1) the emergence of multicellularity
2) the appearance of roots and rhizomes
3) tissue development
4) seed formation
5) the emergence of photosynthesis
6) the occurrence of double fertilization
Answer
3. Establish the correct sequence of the most important aromorphoses in plants. Write down the numbers under which they are indicated.
1) Photosynthesis
2) Seed formation
3) The appearance of vegetative organs
4) The appearance of a flower in the fruit
5) The emergence of multicellularity
Answer
4. Establish the sequence of aromorphoses in the evolution of plants. Write down the corresponding sequence of numbers.
1) the appearance of vegetative organs (roots, shoots)
2) appearance of the seed
3) formation of primitive integumentary tissue
4) flower formation
5) the emergence of multicellular thallus forms
Answer
5. Establish the sequence of processes occurring during the evolution of plants on Earth, in chronological order. Write down the corresponding sequence of numbers in your answer.
1) the emergence of a eukaryotic photosynthetic cell
2) a clear division of the body into roots, stems, leaves
3) landfall
4) the appearance of multicellular forms
Answer
Arrange the structures of plants in the order of their evolutionary origin. Write down the corresponding sequence of numbers.
1) seed
2) epidermis
3) root
4) leaf
5) fruit
6) chloroplasts
Answer
Choose three correct answers out of six and write down the numbers under which they are indicated. Which of the listed aromorphoses occurred after plants reached land?
1) occurrence seed propagation
2) the emergence of photosynthesis
3) division of the plant body into stem, root and leaf
4) the occurrence of the sexual process
5) the emergence of multicellularity
6) the appearance of conductive tissues
Answer
CHORDAL AROMORPHOSES
1. Establish the sequence of formation of aromorphoses in the evolution of chordates
1) the appearance of lungs
2) formation of the brain and spinal cord
3) formation of a chord
4) the appearance of a four-chambered heart
Answer
2. Arrange animal organs in the order of their evolutionary origin. Write down the corresponding sequence of numbers.
1) swim bladder
2) chord
3) three-chambered heart
4) uterus
5) spinal cord
Answer
3. Establish the sequence of appearance of aromorphoses in the process of evolution of vertebrates on Earth in chronological order. Write down the corresponding sequence of numbers
1) reproduction by eggs covered with dense shells
2) formation of limbs ground type
3) the appearance of a two-chamber heart
4) development of the embryo in the uterus
5) milk feeding
Answer
4. Establish the sequence of complication of the circulatory system in chordates. Write down the corresponding sequence of numbers.
1) three-chambered heart without a septum in the ventricle
2) two-chamber heart with venous blood
3) there is no heart
4) heart with an incomplete muscular septum
5) in the heart, the separation of venous and arterial blood flows
Answer
CHORDAL SYSTEM UNITS
1. Establish the sequence of appearance of groups of chordates in the process of evolution.
1) lobe-finned fish
2) reptiles
3) stegocephals
4) skullless chordates
5) birds and mammals
Answer
2. Establish the sequence of evolutionary phenomena in vertebrates. Write down the corresponding sequence of numbers.
1) the rise of dinosaurs
2) the emergence of primates
3) the flourishing of armored fish
4) the appearance of Pithecanthropus
5) the appearance of stegocephals
Answer
3. Establish the sequence of evolutionary processes of the formation of the main groups of animals that occurred on Earth, in chronological order. Write down the corresponding sequence of numbers
1) Skullless
2) Reptiles
3) Birds
4) Bony fish
5) Amphibians
Answer
4. Establish the sequence of evolutionary processes of the formation of the main groups of animals that occurred on Earth, in chronological order. Write down the corresponding sequence of numbers
1) Skullless
2) Reptiles
3) Birds
4) Bony fish
5) Amphibians
Answer
5. Establish the sequence of evolutionary phenomena in vertebrates. Write down the corresponding sequence of numbers.
1) the appearance of Pithecanthropus
2) the appearance of stegocephals
3) the rise of dinosaurs
4) the flourishing of armored fish
5) the emergence of primates
Answer
ARTHOPOD AROMORPHOSIS
Establish the sequence of formation of aromorphoses in the evolution of invertebrate animals
1) the emergence of bilateral symmetry of the body
2) the appearance of multicellularity
3) the appearance of jointed limbs covered with chitin
4) dismemberment of the body into many segments
Answer
ANIMALS SYSTEMS UNITS
1. Establish the correct sequence of appearance of the main groups of animals on Earth. Write down the numbers under which they are indicated.
1) Arthropods
2) Annelids
3) Skullless
4) Flatworms
5) Coelenterates
Answer
2. Establish in what sequence the types of invertebrate animals should be arranged, taking into account their complexity nervous system in evolution
1) Flatworms
2) Arthropods
3) Coelenterates
4) Annelids
Answer
3. Establish the correct sequence in which these groups of organisms supposedly arose. Write down the corresponding sequence of numbers.
1) Birds
2) Lancelets
3) Ciliates
4) Coelenterates
5) Reptiles
Answer
4. Establish the sequence of appearance of groups of animals. Write down the corresponding sequence of numbers.
1) trilobites
2) Archeopteryx
3) protozoa
4) Dryopithecus
5) lobe-finned fish
6) stegocephals
Answer
5. Establish the geochronological sequence of the emergence of groups of living organisms on Earth. Write down the corresponding sequence of numbers.
1) Flatworms
2) Bacteria
3) Birds
4) Protozoa
5) Amphibians
6) coelenterates
Answer
Establish the sequence of complication of the organization of these animals in the process of evolution
1) earthworm
2) common amoeba
3) white planaria
4) Chafer
5) nematode
6) crayfish
Answer
Choose the one that suits you best correct option. The ozone shield first appeared in the Earth's atmosphere as a result of
1) chemical processes occurring in the lithosphere
2) chemical transformations of substances in the hydrosphere
3) vital activity of aquatic plants
4) vital activity of terrestrial plants
Answer
Choose one, the most correct option. Which type of animal has the most high level organizations
1) Coelenterates
2) Flatworms
3) Annelids
4) Roundworms
Answer
Choose one, the most correct option. Which ancient animals were the most likely ancestors of vertebrates?
1) Arthropods
2) Flatworms
3) Shellfish
4) Skullless
Answer
© D.V. Pozdnyakov, 2009-2019
The emergence of unicellular and multicellular algae, the emergence of photosynthesis: the emergence of plants on land (psilophytes, mosses, ferns, gymnosperms, angiosperms).
Development flora took place in 2 stages and is associated with the emergence of lower and higher plants. According to the new taxonomy, algae are classified as lower (and previously included bacteria, fungi and lichens. Now they are separated into independent kingdoms), and mosses, pteridophytes, gymnosperms and angiosperms are classified as higher.
In the evolution of lower organisms, two periods are distinguished, which differ significantly in the organization of the cell. During period 1, organisms similar to bacteria and blue-green algae dominated. The cells of these life forms did not have typical organelles (mitochondiria, chloroplasts, Golgi apparatus, etc.). The cell nucleus was not limited by the nuclear membrane (this is a prokaryotic type of cellular organization). Period 2 was associated with the transition of lower plants (algae) to an autotrophic type of nutrition and with the formation of a cell with all the typical organelles (this is a eukaryotic type of cellular organization, which was preserved at subsequent stages of development of the plant and animal world). This period can be called the period of dominance of green algae, unicellular, colonial and multicellular. The simplest of multicellular organisms are filamentous algae (ulotrix), which do not have any branching in their body. Their body is a long chain consisting of individual cells. Other multicellular algae are dismembered big amount outgrowths, so their body branches (in Hara, in Fucus).
Multicellular algae, due to their autotrophic (photosynthetic) activity, evolved in the direction of increasing their body surface for better absorption nutrients from aquatic environment And solar energy. Algae have a more progressive form of reproduction - sexual reproduction, in which a new generation begins with a diploid (2n) zygote, combining the heredity of 2 parental forms.
The 2nd evolutionary stage of plant development must be associated with their gradual transition from an aquatic to a terrestrial lifestyle. The primary terrestrial organisms turned out to be psilophytes, which were preserved as fossil remains in Silurian and Devonian deposits. The structure of these plants is more complex compared to algae: a) they had special organs of attachment to the substrate - rhizoids; b) stem-like organs with wood surrounded by phloem; c) rudiments of conducting tissues; d) epidermis with stomata.
Starting with psilophytes, it is necessary to trace 2 lines of evolution of higher plants, one of which is represented by bryophytes, and the second by ferns, gymnosperms and angiosperms.
The main thing that characterizes bryophytes is the predominance of the gametophyte over the sporophyte in their individual development cycle. The gametophyte is everything green plant capable of self-feeding. The sporophyte is represented by a capsule (cuckoo flax) and is completely dependent on the gametophyte for its nutrition. The dominance of the moisture-loving gametophyte in mosses under the conditions of an air-terrestrial lifestyle turned out to be impractical, so mosses became a special branch of the evolution of higher plants and have not yet given rise to perfect groups of plants. This was also facilitated by the fact that the gametophyte, compared to the sporophyte, had poor heredity (haploid (1n) set of chromosomes). This line in the evolution of higher plants is called gametophytic.
The second line of evolution on the path from psilophytes to angiosperms is sporophytic, because in ferns, gymnosperms and angiosperms the sporophyte dominates in the cycle of individual plant development. It is a plant with a root, stem, leaves, sporulation organs (in ferns) or fruiting organs (in angiosperms). Sporophyte cells have a diploid set of chromosomes, because they develop from a diploid zygote. The gametophyte is greatly reduced and is adapted only for the formation of male and female germ cells. In flowering plants, the female gametophyte is represented by the embryo sac, which contains the egg. The male gametophyte is formed when pollen germinates. It consists of one vegetative and one generative cell. When pollen germinates, 2 sperm arise from the generative cell. These 2 male reproductive cells are involved in double fertilization in angiosperms. The fertilized egg gives rise to a new generation of the plant - the sporophyte. The progress of angiosperms is due to the improvement of the reproductive function.
Planet Earth was formed more than 4.5 billion years ago. The first single-celled life forms appeared perhaps about 3 billion years ago. At first it was bacteria. They are classified as prokaryotes because they do not have a cell nucleus. Eukaryotic (those with nuclei in 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, plant cell formed by the entry into a heterotrophic eukaryotic cell of a photosynthetic bacterium that was not digested. Further, the process of evolution led to the appearance 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 great diversity and lived exclusively in water.
The surface of the Earth did not remain unchanged. Where Earth's crust rose, land gradually appeared. Living organisms had to adapt to new conditions. Some ancient algae were gradually able to adapt to a terrestrial lifestyle. In the process of evolution, their structure became more complex, tissues appeared, primarily integumentary and conductive.
The first land plants are considered to be psilophytes, which appeared about 400 million years ago. They have not survived to this day.
Further evolution of plants, associated with the complication of their structure, took place on land.
During the time of the psilophytes, the climate was warm and humid. Psilophytes grew near bodies of water. They had rhizoids (like roots), with which they anchored themselves in the soil and absorbed water. However, they did not have true vegetative organs (roots, stems and leaves). Promotion of water and organic matter the plant was provided by the emerging conductive tissue.
Later, ferns and mosses evolved from psilophytes. These plants have more complex structure, they have stems and leaves, they are better adapted to living on land. However, just like psilophytes, they remained dependent on water. During sexual reproduction, in order for the sperm to reach the egg, they need water. Therefore, “go away” far from wet places they could not live.
In the Carboniferous period (about 300 million years ago), when the climate was humid, ferns reached their dawn, and many of them grew on the planet. wood forms. Later, dying off, it was they who formed coal deposits.
When the climate on Earth began to become colder and drier, ferns began to die out en masse. But some of their species before this gave rise to the so-called seed ferns, which in fact were already gymnosperms. In the subsequent evolution of plants, seed ferns became extinct, giving rise to other gymnosperms. Later, more advanced gymnosperms appeared - conifers.
The reproduction of gymnosperms no longer depended on the presence of liquid water. Pollination occurred with the help of wind. Instead of sperm (mobile forms), they formed sperm (immobile forms), which were delivered to the egg special education pollen grain. In addition, gymnosperms produced not spores, but seeds containing a supply of nutrients.
The further evolution of plants was marked by the appearance of angiosperms (flowering plants). This happened about 130 million years ago. And about 60 million years ago they began to dominate the Earth. Compared to gymnosperms, flowering plants better adapted for life on land. You could say they began to take advantage of opportunities more environment. So their pollination began to occur not only with the help of the wind, but also with the help of insects. This increased pollination efficiency. Angiosperm seeds are found in fruits, which allow them to spread more efficiently. 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.
1. Indicate the correct sequence of appearance of organisms on Earth.
1) algae – bacteria – mosses – ferns – gymnosperms – angiosperms
2) bacteria – algae – mosses – ferns – angiosperms – gymnosperms
3) bacteria – algae – mosses – ferns – gymnosperms – angiosperms
4) algae – mosses – ferns – bacteria – gymnosperms – angiosperms
2. Establish the sequence of appearance of the main groups of plants on Earth in the process of evolution.
1) psilophytes
2) unicellular green algae
3) multicellular green algae
3. Establish the sequence of complication of organisms in the process historical development organic world on Earth.
1) formation of chlorophyll in cells
2) the appearance of rhizoids
3) fruit formation
4) the appearance of roots, stems, leaves
5) the emergence of unicellular heterotrophic organisms
4. Establish the sequence of increasing complexity of the organization of organisms in the process of historical development of the organic world on Earth.
1) the emergence of photosynthesis
2) development of seeds in cones
3) the occurrence of double fertilization
4) the emergence of heterotrophic organisms
5) participation of oxygen in metabolic processes in cells
5. In connection with the emergence of the first plants on land, they developed
1) vegetative organs 2) seeds 3) spores 4) gametes
6. What feature of flowering plants contributed to their widespread distribution in the Cenozoic era?
1) the presence of flowers and fruits
2)increasing life expectancy
3) diversity of vegetative organs
4) the appearance of various plastids
1) the seeds contain an embryo with a supply of nutrients
2) animals eat seeds
3) seeds are spread by the wind
4) the seeds lie openly on the scales of the cones
8. Ancient ferns became extinct in the process of evolution because
1) they were destroyed by animals
2) used them intensively ancient man
3) there was a cooling and a decrease in air humidity
4) flowering plants appeared
9. The evolution of plants went in the direction
1)reduced life expectancy
2)development of new environments and habitats
3) maintaining the dependence of fertilization on water
4) preservation of the gametophyte as the main stage of development
10. Which of the listed groups of plants was the first during evolution to cease to depend on the presence of water for fertilization?
11. Mammals evolved from the ancients
1) dinosaurs 2) animal-toothed lizards
3) lobe-finned fish 4) tailed amphibians
12. The picture shows a print of Archeopteryx. He is a fossil transitional form between the ancients
1)birds and mammals
2) reptiles and birds
3) reptiles and mammals
4) amphibians and birds
13. What sign indicates the relationship of Archeopteryx with modern birds?
1) fingers with claws on the forelimbs
2) tarsus in the hind limbs
3) small teeth in the jaws
4) caudal region in the spine
14. What ancient fish did amphibians originate from?
1) sharks and rays 2) sturgeons and belugas 3) lozenges 4) bonefish
15. Many scientists consider it a fossil transitional form between the ancients
1) fish and amphibians 2) reptiles and birds
3) fish and reptiles 4) amphibians and birds
16. In the process of evolution, the appearance of a five-fingered limb in animals is associated with
1) transition to a terrestrial lifestyle
2) the need to climb trees
3) the need to make tools
4) active movement in the water column
17. Dismembered limbs in animals were formed in the process of evolution as an adaptation to movement in
1) water 2) air 3) soil 4) ground-air environment
18. In the process of evolution, the emergence of a second circle of blood circulation in animals led to the emergence
1) gill respiration 2) pulmonary respiration
3) tracheal breathing 4) breathing over the entire surface of the body
19. The most likely ancestors of reptiles were
1) newts 2) archeopteryx
3) ancient amphibians 4) lobe-finned fish
20. Which ancient animals are considered the ancestors of reptiles?
1) ichthyosaurs 2) archeopteryx
3) stegocephali 4) lobe-finned fish
21. In what era did reptiles dominate on Earth?
1) Mesozoic 2) Archean
3) Cenozoic 4) Paleozoic
22. From ancient reptiles came:
1) birds and mammals 2) lungfishes and molluscs
3) coelenterates and worms 4) fish and amphibians
23. Establish the hypothetical sequence of occurrence of the following groups of animals:
A) Flying insects
B) Reptiles
B) Primates
D) Annelids
D) Flatworms
E) Coelenterates
24. Establish the sequence of stages in the development of the animal world of the Earth from the most ancient to the modern:
A) the appearance of stegocephals
B) dominance of marine invertebrates
B) reptilian dominance
D) the appearance of cartilaginous fish
D) the appearance of bony fish
25. Establish the sequence of increasing complexity of animal organization in the process of historical development of the organic world on Earth. Write down the corresponding sequence of numbers in your answer.
1) the appearance of the cortex in the cerebral hemispheres
2) formation of chitinous cover
3) the emergence of radial symmetry of the body
4) development of the intestine with oral and anal openings
5) appearance of jaws in the skull
As a result of prehistoric events such as the Permian and Cretaceous–Paleogene, many plant families and some ancestors existing species became extinct before recorded history began.
The general trend of diversification includes four main groups of plants that dominate the planet from the Middle Silurian period to the present:
Zosterophyllum model
- The first main group, representing terrestrial vegetation, included seedless vascular plants represented by the rhinium classes ( Rhynophyta), zosterophylls ( Zosterophyllopsida).
Ferns
- The second main group, which appeared in the late Devonian period, consisted of ferns.
- The third group, seed plants, appeared at least 380 million years ago. It included gymnosperms ( Gymnospermae), which dominated the terrestrial flora during most of the Mesozoic era until 100 million years ago.
- The final fourth group, the angiosperms, appeared about 130 million years ago. The fossil record also shows that this group of plants was abundant in most areas of the world between 30 million and 40 million years ago. Thus, angiosperms dominated the Earth's vegetation for almost 100 million years.
Palaeozoic
Moss-moss
The Proterozoic and Archean eons precede the appearance of terrestrial flora. Seedless, vascular, terrestrial plants appeared in the mid-Silurian period (437-407 million years) and were represented by rhinophytes and possibly lycophytes (including Lycopodium). From primitive rhyniophytes and lycophytes, land vegetation evolved rapidly during the Devonian period (407-360 million years ago).
The ancestors of true ferns may have evolved in the mid-Devonian. During the late Devonian period, horsetails and gymnosperms appeared. By the end of the period, all the main divisions of vascular plants, except angiosperms, already existed.
The development of the characteristics of vascular plants, during the Devonian, allowed an increase in the geographical diversity of the flora. One of them was the appearance of flattened leaves, which increased efficiency. Another is the emergence of secondary wood, allowing plants to greatly increase in shape and size, leading to trees and probably forests. The gradual process was the reproductive development of the seed; the earliest was found in Upper Devonian deposits.
The ancestors of conifers and cycads appeared in the Carboniferous period (360-287 million years ago). During the Early Carboniferous in high and middle latitudes, vegetation shows dominance of Lycopodium and Progymnospermophyta.
Progymnospermophyta
In the lower latitudes of North America and Europe, a wide variety of Lycopodiums and Progymnospermophyta, as well as other vegetation. There are seed ferns (including calamopityales), along with true ferns and horsetails ( Archaeocalamites).
Late Carboniferous vegetation at high latitudes was greatly affected by the onset of the Permian-Carboniferous ice age. In the northern mid-latitudes, the fossil record shows the dominance of horsetails and primitive seed ferns (pteridosperms) over few other plants.
In the northern low latitudes, the land masses of North America, Europe and China were covered by shallow seas or marshes and, because they were close to the equator, experienced tropical and subtropical climatic conditions.
At this time, the first ones known as coal forests appeared. A huge amount of peat was laid as a result favorable conditions year-round growth and adaptation of giant Lycopodium to tropical wetland environments.
In the drier areas surrounding the lowlands, forests of horsetails, seed ferns, cordaites and other ferns existed in great abundance.
The Permian period (287-250 million years ago) indicates a significant transition of conifers, cycads, glossopteris, gigantopterids and peltasperms from poor fossil record in the Carboniferous to significant abundant vegetation. Other plants, such as tree ferns and giant lycopodiums, were present in the Permian, but not in abundance.
As a result of the Permian mass extinction, tropical swamp forests disappeared, and with them the Lycopodiums; Cordaites and Glossopteris became extinct at higher latitudes. About 96% of all plant and animal species disappeared from the face of our planet at this time.
Mesozoic era
At the beginning of the Triassic period (248-208 million years ago), the sparse fossil record indicates a decline in the Earth's flora. From the mid to late Triassic, modern families of ferns, conifers, and a now extinct group of plants, the Bennettites, inhabited most terrestrials. After the mass extinction, Bennettites moved into vacant ecological niches.
Late Triassic flora in equatorial latitudes includes a wide range of ferns, horsetails, cycads, bennettites, ginkgos and conifers. Plant combinations in low latitudes are similar, but not rich in species. This lack of plant variation at low and mid-latitudes reflects a global frost-free climate.
In the Jurassic period (208-144 million years ago), terrestrial vegetation similar to modern flora appeared, and modern families can be considered descendants of ferns of this geological period of time , such as Dipteridaceae, Matoniaceae, Gleicheniaceae, and Cyatheaceae.
Conifers of this age may also include modern families: podocarpaceae, araucariaceae, pine and yew. These conifers, during the Mesozoic, created significant deposits of such things as coal.
During early and middle Jurassic period, in the equatorial latitudes of western North America, Europe, Central Asia And Far East, a variety of vegetation grew. It included: horsetails, cycads, bennettites, ginkgos, ferns and coniferous trees.
Warm, wet conditions also existed in the northern mid-latitudes (Siberia and northwestern Canada), supporting ginkgo forests. Deserts were found in the central and eastern parts of North America and North Africa, and the presence of Bennettites, cycads, Cheirolepidiaceae and conifers indicated the adaptation of plants to arid conditions.
Southern latitudes had similar vegetation to equatorial latitudes, but due to drier conditions, conifers were abundant and ginkgos were scarce. Southern flora has spread to very high latitudes, including Antarctica, due to the lack polar ice.
Cheirolipidae
During the Cretaceous period (144-66.4 million years ago) in South America, Central and North Africa, And Central Asia there were dry, semi-desert natural conditions. Thus, the terrestrial vegetation was dominated by Cheirolipidium conifers and Matoniaceae ferns.
The northern mid-latitudes of Europe and North America had more diverse vegetation consisting of Bennettites, cycads, ferns and conifers, while the southern mid-latitudes were dominated by Bennettites.
The Late Cretaceous saw significant changes in the Earth's vegetation, with the emergence and spread of flowering seed plants, the angiosperms. The presence of angiosperms meant the end of the typical Mesozoic flora dominated by gymnosperms and a definite decline in the Bennettites, Ginkgoaceae and Cycads.
Nothofagus or southern beech
During the Late Cretaceous, arid conditions prevailed in South America, central Africa and India, resulting in palm trees dominating tropical vegetation. The mid-southern latitudes were also influenced by deserts, and the plants that bordered these areas included: horsetails, ferns, conifers and angiosperms, particularly nothofagus (southern beech).
Sequoia Hyperion
High latitude areas were devoid of polar ice; Due to warmer climate conditions, angiosperms were able to thrive. The most diverse flora has been found in North America, where evergreens, angiosperms and conifers were present, especially redwood and sequoia.
Cretaceous-Paleogene mass extinction (K-T extinction) occurred about 66.4 million years ago. This is an event that suddenly caused global climate change and the extinction of many animal species, especially dinosaurs.
The greatest “shock” to terrestrial vegetation occurred in the mid-latitudes of North America. Pollen and spore counts are slightly higher borders K-T the fossil record shows a predominance of ferns and evergreens. Subsequent plant colonization in North America shows a predominance of deciduous plants.
Cenozoic era
Increased rainfall at the beginning of the Paleogene-Neogene (66.4-1.8 million years ago) contributed to the widespread development of rain forests in the southern regions.
Notable during this period was the Arcto polar forest flora found in northwestern Canada. Mild, humid summers alternated with continuous winter darkness with temperatures ranging from 0 to 25°C.
Birch Grove
These climatic conditions supported deciduous vegetation, which included sycamore, birch, moonsperm, elm, beech, magnolia; and gymnosperms such as Taxodiaceae, Cypressaceae, Pinaceae and Ginkgoaceae. This flora spread throughout North America and Europe.
Approximately eleven million years ago, during the Miocene Epoch, marked changes in vegetation occurred with the emergence of grasses and their subsequent expansion into grassy plains and prairies. The appearance of this widespread flora contributed to the development and evolution of herbivorous mammals.
The Quaternary period (1.8 million years ago to the present) began with continental glaciation in northwestern Europe, Siberia and North America. This glaciation affected land vegetation, with flora migrating north and south in response to glacial and interglacial fluctuations. During interglacial periods, maple, birch and olive trees were common.
The final migrations of plant species at the end of the last Ice Age (about eleven thousand years ago) shaped the modern geographic distribution of land flora. Some areas, such as mountain slopes or islands, have unusual species distributions as a result of their isolation from global plant migration.