400 million years ago, the sea and oceans occupied a huge part of the earth's surface of our planet. The first living organisms arose in an aquatic environment. They were mucus particles. After several millions of years, these primitive microorganisms have a green color. In appearance, they began to resemble algae.
Climatic conditions have favorably affected the growth and reproduction of algae.
Over time, the surface of the Earth and the bottom of the oceans was subjected to changes. There were new main students, the old were disappeared under water. The earth is actively changed. These processes led to the fact that water appeared on the site of the earth's surface.
Departing, marine water fell into crevices, depressions. They sworn, they were filled again with water. As a result, those algae who were on the seabed were gradually moved to the earth's surface. But since the process of the drainage took place very slowly, during this time they adapted to new habitat on earth. This process took place throughout a million years.
The climate at that time was very wet and warm. He contributed to the transition of plants from marine life to ground. Evolution led to the complication of the structure of various plants, algae also changed. They gave rise to the development of new earth plants - plyphitis. In appearance, they resembled small plants that were placed near the shores of lakes rivers. They possessed the stem, which was covered with small bristles. But, like by algae, the pylofs had no root system.
Ferns occurred from psulifitis. The psiliefs themselves 300 million years ago ceased to exist.
The wet climate and a large amount of water led to the rapid spread of different plants - ferns, horsages, plane. The end of the coal period was marked by changing the climate: it became more dry and cold. Huge ferns began to dy up. The remains of dead plants rotted and turned into a stone coal, which people then heated their homes.
Ferns on the leaves lay seeds that were called the vote plants. From gigantic ferns, modern pines, ate, fir, which are called gone plants occurred.
Ancient ferns disappeared with climate change.
Cold climate ruined their gentle sprouts. They were replaced by seed ferns, which are called the first viced plants. These plants perfectly adapted to the new conditions of dry and cold climate. This type of plant has the reproduction process did not depend on the water, which is in the external environment.
130 million years ago various shrubs and herbs arose on Earth, whose seeds were in the surface of the fruit. They were called coated plants. Over the course of 60 million years, coated plants live on our planet. These plants have practically not changed since then to the present day.
Without plants, our planet would be a lifeless desert. And the leaves of trees are small factories or chemical laboratories, where substances converts substances under the influence of sunlight and heat. Trees not only improve the composition of the air and soften its temperature. The forest is of therapeutic importance, it also provides most of our food needs, as well as in materials such as wood and cotton; They are raw materials for the production of drugs.
I. What were the most first plants on earth?
Life on Earth began at sea. And the first on our planet appeared plants. Many of them got on land and became completely different. But those that remained at sea almost did not change. They are the most ancient, it all started with them. Without plants, life on Earth would be no possible. Only plants are able to absorb carbon dioxide and allocate oxygen. For this, they use sun rays. Some of the first plants on the ground were algae.
More than 20,000 species of algae are known. They can be fixed on the rocks or on the seabed with a similar to the foot of the "brackets", which goes into a branch with sheets. Brown algae grow in cold waters and achieve huge sizes. Red algae is characteristic of warm seas. Green and blue - green algae can be found both in warm and cold waters. Of the brown algae, many useful substances used in the production of plastics, varnishes, paints, paper and even explosives are obtained. Of them make medicines, fertilizer, feeding for livestock. The peoples of Southeast Asia, algae are the basis of a variety of dishes.
Algae "floating forest".
In the old days there were legends about Sargasso Sea, where ships gibbles, stuck in algae. But nevertheless, the thickets of the algae thick are so much that they can delay the light boat. These are brown algae-Sargass, in honor of which the sea itself is called. Sargasss are similar to the bushes of dyed "berries" - air bubbles allowing the plant to keep on the surface of the water. Unlike other major algae, Sargasss are not attached to the bottom and huge clusters are traveled through the waves and forming a floating forest. The inconspicuous amount of mollusks, worms, msnok are attached to the leaves of Sargass, the crabs, shrimps and fish are hidden in its thickets. Almost all the "residents" of brownish yellow color, in the tone of Sargass, and their bodies often copy the forms of "leaves" of this algae. Some are hidden to keep them with a sacrifice. So floats all this community, never sticking to the shore.
II. Feed, dress, please.
1. Trees that give food.
Coffee is one of the most popular drinks in the world.
Who and how did this wonderful drink gave us? If you believe the ancient Arab legend, we owe the cost of coffee. goat. One Ethiopian shepherd, says legend, noticed that his goats, sowing some berries with bush, continued to graze all night, and without thinking to rest. The shepherd spoke about this to the Mudroma Starta, and the one who tasted these berries, opened their wonderful strength and invented the drink of coffee.
The coffee was so liked by Ethios, which later one of the tribes, moved to the Arabian Pn, captured with his grains. So it was the beginning of the first coffee plantations. A happened, as is known from ancient manuscripts, in the 9th century. Coffee was known for quite a long time to be known to the Arabs, but the Turks who won in the XV-XVI centuries. Part of the Arab territories also estimated the taste and wonderful properties of the beverage. So there was a famous way to prepare coffee in Turkish: coffee is boiled on hot sand in special copper vessels with handle - "Turks".
For the first time, the Europeans introduced a certain Italian, who returned from Turkey. The doctor in the specialty, he recommended his patients to drink coffee for medical purposes. Venice of the first began to import coffee to Europe. And in 1652 the first coffee shop and in England was opened. Turkey's monopoly supplier in Europe was Turkey, but the sly Dutch, having spared coffee trees seedlings, transported them to Indonesia, where the climate was completely suitable for growing coffee.
Now Brazil has become the world leader in the production of coffee.
Coffee came to Russia thanks to Peter 1.
Drink coffee boil from treated seeds coffee tree. it evergreen From the Marines family. White lush inflorescences of a coffee tree, located in the sinuses of the leaves, after pollination insects turn into the fruit - the red berries with them remove the flesh, the seeds are polished in special drums and pack in bags. Before brewing coffee beans roasted.
Motherland coffee - Africa. The highest quality and tasty is the Arabian view. Brazilian coffee (this is not a view, but only the place of cultivation of coffee), which are filled with all the markets of the world, in quality is much worse than coffee grown in other countries.
2. Noble friends.
Cedras are real cedar. Phenicia, Egypt, Assyrias were mighty powers of antiquity. But the territories they occupied the deserted, forests there were almost no. And wood is needed for the construction of housing, and for ships. Wood strong, non-burning. Cedar, which fell in love with ancient, is not the cedar that grows in the taiga and is famous for its delicious nuts. Siberian pines "Single-Famils" of real cedars - cedars.
The Phoenicians cut the cedars on the ships, the Egyptians - on sarcophages for the funeral ceremonies of their nobles, the Greeks and Romans used cedar for the construction of temples and the manufacture of furniture. Later, crusaders began to cut the cedges. And during the First World War, the most valuable samples with their pink wood, for the absence of other fuels, burned in steaming furnaces. That remains only 4 groves of Lebanese cedars. True, other types of cedars - Atlas, Cyprus and Himalayan, although very rare trees, but unlike the Lebanese cedar, not disappearing.
Lebanese cedar - magnificent trees with horizontal powerful branches. They have a bluish, collected in brush. Corses with fist the size, dense, almost smooth, like barrels. When the seeds ripen in them, the bumps are not disclosed, but they crumble, and the earth is covered with a layer of scales. The wind blows the winged seeds with them and spread around the district. If the goats, who are abundant by local residents, do not eat young shoots, can grow a new generation of handsome ceders. Glory about the beauty of Lebanese cedar reached Russia. Therefore, when Russian pioneers saw siberian pines, High, majestic, with large bumps, they called them cedars.
Siberian cedar - pine amazing. The main wealth of cedar is his nuts. They contain fats, proteins, starch, vitamins B and D and in needles contain many healing substances. Nuts contain more than 60% of oil, which in many qualities exceeds animal fats and is not inferior in nutrition to meat and eggs. With Ivan Grozny, these nuts were exported abroad, and in Peter I, the healing and strengthening agent began to prepare in Russia - walnut milk.
The cedar nuts in the life of animals play a huge role. "Where there is no cedar," the hunters say, "there is no sable". Nuts eating bears and chipmunks, squirrels and various birds.
Celex and cedar resin - Zhivitsa. During the Great Patriotic War Cedar balm saved in injuries and burns. Zhivitsa is the necessary raw materials to obtain such a valuable medicine as camphor. We need a savage and optical equipment.
Cedar's valuable and wood - pencil sticks are produced from it, musical instrumentsFurniture manufactures. Skipidar and other useful products are obtained from sawdust.
III. Study of tree bark.
Maple sharply
Maple for whom I watched, young. He has a woody trunk, which is thickened with each year, the side branches forming the crown, which consists of smaller branches, leaves. The tree is held in the soil roots that absorb moisture and mineral substances dissolved in it. Therefore, at the bottom of the tree trunk is wider.
If you smell a bark, then the smell is bitter, binding. In the spring the smell of the cortex is enhanced and becomes sweet.
B my vapla tree is not. But I met the trees with a hollow. B Hungry is arranged by dwellings various birds.
On a cool for which I observe neither lichens, mosses and mushrooms. Sometimes mushrooms form mbocornia on the roots, supplying trees with nitrogen and minerals.
On the crust of my tree there are traces left by a person: an encouraged bark and scratches from the knife, which over time it could heal.
IV. Why my friend is the best.
Klelen Ostolish - branch with fruits
Maple one of the most elegant trees growing in our forests. In the spring, when the branches of the trees were not yet covered with leaves, maple blooms. Its yellow-green flowers collected in the inflorescence, please the eye. No less nailed by Klen in the summer, when his crown becomes a "curly". Autumnal outfit will not give up a beauty to a single plant. The tree is like burning, hitting the richness of the shades of crimson and green, orange and yellow. Each sheet has its own color, and each sheet is beautiful in its own way. And all one form is one: rounded with 5-7 sharp protrusions, hence the name of the maple is sharply. Maple good honey. From one tree get up to 10 kg of honey. Juicy maple juice is very tasty. In Russia, Kvass prepared from it, various soft drinks.
On the flag of Canada there is a sheet of sugar maple. Of his sweet juice, maple syrups, a molasses and even maple beer were made, a very popular 19th century. The leader in the production of products from juice was Canada. Maple leaf has become a national symbol of this country.
Maple wood - durable and easy made musical instruments. Sports inventory are also made of maple. Pharmacists and chemists use leaves and bark. Maple has another interesting property: he can predict the weather. From the pets of the leaves, at the twig itself, sometimes the droplet behind the droplet flow "tears" - the maple seems to be crying. This property of maple get rid of excess moisture. And the "tears" of maple depends on, dry or is dominated. Than the air land, the stronger evaporation and vice versa. Wet air becomes rain. If they appeared on the maple leaves "tears, then it will rain in a few hours.
V. Fossil trees that remained on Earth.
Ancient-ancient Ginkgo tree! It appeared on Earth at the time of dinosaur-125 million.
years ago. And since then, this plant has almost changed. Ginkgo is a beautiful tree with a height of up to 30 m, with large fan-like leaves. The appearance of Ginkgo reminds our ordinary Osin. But it was not there! Ginkgo - a gamotered plant, closer to ate than to a flowering plant is aspen. Spring on the branches together with the foliage appear "Earrings". By autumn on the branches hang large seeds resembling plums. The flesh of seed, looks like a fruit, in fact only seed shell. She is edible and the taste of saltwate. One trouble - smells with rotten meat. This is a way to attract animal distributors of seeds. Ginkgo, although survived dinosaurs, not survived in the wild. This tree has become a garden. In Japan and China, it is considered sacred - it is grown near the temples. Now Ginkgo appear on the streets of European cities. Ginkgo is easily opposed and contamination of the atmosphere, and diseases, and insects. In the leaves and wood ginkgo contain substances that scare insects. Bookmarks made of dried ginkgo leaves will be removed by ancient manuscript from book worms. And the walls covered with duch ginkgo will not be allowed into the house neither cockroaches nor bugs.
Conclusion.
What can I do for all trees?
Coming into the forest, I will not give fires.
This can lead to fires.
I will not ruin the bird nests. Birds eat insects who harm trees. I will not break the branches in trees and shrubs. In the courtyard I will plant new seedlings and to care for them in the future.
Acid rains also apply irreparable damage: the death of crops, flora and fauna, the destruction of buildings.
Life originated in the water. The first plants appeared here - algae. However, at some point there was a land sushi, which was to be populated. Cystic fish are filmmakers among animals. And among plants?
Once our planet inhabited plants that had only stem. To the ground they were attached to special growth - rhizoids. These were the first plants who were seen on the land.
Scientists are called their pylofitis. This is a Latin word. Translated it means "bare plants". Psulfiti really looked "bare." They had only branched stalks with the balls-balls in which disputes were kept. They are very similar to "alien plants", which are depicting illustrations to fantastic stories.
Psulfitis became the first terrestrial plants, but they lived only in a swampy terrain, as they had no root, and they could not produce water and nutrients in the soil thicker. Scientists believe that once these plant created whole huge carpets over the naked surface of the planet. There were both tiny plants and very large, above human growth.
The fact that there were such plants on our planet, scientists learned only at the beginning of the last century, in 1912, thanks to one Scottish rural doctor who passed the geology. Exploring the soil, he discovered the remains of unknown plants, which were subsequently called Riniya, by the name of the village in which it was first found. It is believed that this was the first land plant, there were other psiliefs from him.
The ancient plants dominated the planet millions of years, but extinct long before the appearance of a person. But they left their "descendants" - they became horsetails, plaunas and ferns. Some scientists believe that the lower plysofitis became the progenitors of modern MSOs.
the embryonic stage of the seed plant formed in the process of sexual reproduction and serving for the settlement. Inside the seed is a germ consisting of germ roots, a stalk and one or two leaves, or cotyledons. Flower plants by the number of cotyledons are divided into two-bedroom and monocoons. In some species, such as orchids, individual parts of the embryo are not differentiated and begin to form from certain cells immediately after germination.
A typical seed contains a supply of nutrients for the embryo, which for some time will have to grow without the light necessary for photosynthesis. This stock may occupy the greatest part of the seed, and sometimes located inside the germ itself - in its seedlings (for example, in pea or beans); Then they are large, fleshy and determine the general shape of the seed. In the germination of the seed, they can be carried out of the Earth on the extensioning stalk and become the first photosynthetic leaves of the young plant. Odnochess (for example, wheat and corn) food supply - so-called. Endosperm is always separated from the embryo. Ground endosperm grain crops is a well-known flour.
In coated plants, the seed develops from a seed - tiny thickening on the inner wall of the margin, i.e. The bottom of the pestle, located in the center of the flower. In Zavazy, it can be from one to several thousand seeds.
Each of them is an egg. If, as a result of pollination, it fertilizes sperm penetrating into the wounded of pollen grain, the seedwork develops into the seed. It grows, and its shell becomes dense and turns into a two-layer seed peel. The inner layer is colorless, mucous and capable of swelling, absorbing water. It will come in handy later when the growing germin will have to break through the seed peel. The outer layer can be oily, soft, film, hard, paper and even rigid. On seed peel is usually noticeable. Rubber - a plot that the seed has connected with a seed, attached it to the parent organism.
The seed is the basis of the existence of a modern vegetable and animal world. Without seed on the planet, there would be no coniferous taiga, deciduous forests, blooming meadows, steppes, bread fields, there would be no birds and ants, bees and butterflies, man and other mammals. All this appeared only after the plants during the evolution arose seeds, within which life can, in no way declare themselves, persist for weeks, months and even over the years. Miniature vegetable embryo in the seed is able to travel for distant distances; He is not tied to the ground roots, like his parents; It does not need water or oxygen; He is waiting for his hour to get into appropriate place And waiting for favorable conditions, start the development, which is called the germination of the seed.
Hundreds of millions of years, life on Earth managed without seeds, as it costs without them and now on the water-covered two thirds of the surface of the planet. Life originated in the sea, and the first plants that won the land were still earned, but only the emergence of seeds allowed photosynthesizing organisms to fully master this new habitat for them.
Among the major organisms, the first attempt to consolidate on land took, most likely, marine macrophytes - algae, which were on the stones heated by the sun during the low tide. They multiplied by disputes - single-cell structures scattered by the parent organism and able to develop into a new plant. Algae disputes are surrounded by thin shells, so do not tolerate drying. Under water such protection is quite enough. The disputes there are distributed by the currents, and since the water temperature fluctuates relatively little, they do not need to wait for the conditions favorable for germination.
The first terrestrial plants also multiplied with disputes, but the obligatory change of generations has already been fixed in their life cycle. The sexual process included in it ensured the combination of hereditary signs of the parents, as a result of which the offspring combined the merits of each of them, becoming larger, rushing, perfectly in structure. At a certain stage, such a progressive evolution led to the emergence of liver, moss, plauines, ferns and horsages, which have already completely released from water bodies. However, the dispute breeding has not allowed them to spread beyond the limits of swamp places with wet and warm air.
At this stage of the development of the Earth (approximately 250 million years ago), gigantic forms with partially decisive trunks appeared among the fernal and plauinoids. It was not inferior to them in size and horsages, the hollow stems of which were covered with green bark impregnated with silica. Everywhere, where the plants appeared, animals followed them, mastering new types of habitats for themselves. In a wet twilight of coal jungle, a variety of large insects were found (up to 30 cm long), giant multi-ninexes, spiders and scorpions, amphibians, similar to huge crocodiles, and salamander. Dragonflies with a scope of the wings of 74 cm and cockroaches with a length of 10 cm.
Tree ferns, planes and horses have had all the qualities necessary for habitat on land, except for one - they have not formed seeds. Their roots were effectively absorbed by water and mineral salts, the vascular system of trunks reliably exposed to all organs necessary for the life of the substance, the leaves were actively synthesized organic matter. Even the disputes were improved and acquired a durable cellulose shell. Not afraid of drying, they can be spread by the wind at considerable distances and could not germinate immediately, but after a certain period of rest (so-called resting disputes). However, even the most perfect dispute is unicellular education; In contrast to seeds, it dries quickly and does not contain a supply of nutrients, and therefore it is not capable of waiting for the conditions favorable for the development. Nevertheless, the formation of resting dispute was an important milestone towards seed plants.
Many millions of years the climate on our planet remained warm and wet, but the evolution in fertile wildering coal marshes did not stop. Vidoid spore plants first emerged primitive forms of real seeds. There were seed ferns, plane-shaped (famous representatives of the kind Lepidodendron. - In Greek, this name means "scaly tree") and cordates with solid wood trunks.
Although the fossil remains of these living hundreds of millions of years ago, there are few organisms ago, it is known that the tree seed ferns appeared before the coal period. In the spring of 1869, the Skolhari Creek River in the mountains of Katskill (PC. New York) spilled very much. The flood of demolished the bridges, threw the trees and very much washed the shore at the village of Gilboa. This incident would have forgotten a long time if the water had not discovered the impact collection of strange stumps. The bases were greatly expanded, as in swamp trees, the diameter reached 1.2 m, and age was 300 million years. The details of the structure of the bark are well preserved, fragments of branches and leaves were scattered nearby. Naturally, all this, including IL, from which the stumps were raised, was petrified. Geologists dated fossil residues by the top Devon - the period preceding the coal, and determined that they correspond to tree fern. For the next fifty years, only Paleobotanists remembered about Nakhodka, and then Gilboa's village presented another surprise. Together with the petrified trunks of the ancient ferns, this time was discovered by their branches with real seeds. Now these extinct trees belong to the family EospermatopterisWhat is translated as "Dawn Seed Fern". ("Dawn", because we are talking about the earliest on Earth seed plants).
The legendary coal period ended when the geological processes complicated the relief of the planet, leaning its surface in the fold and dismembering the ridges. Milk swamps were buried under a powerful layer of sedimentary rocks. The continents changed their outlines, sweating the sea and rejected from the previous course ocean flows, the ice caps began to grow, and the huge sushi spaces covered the red sand. Giant ferns, plans and horses extinct: their disputes were not adapted to a more severe climate, and the attempt to move to the reproduction of the seeds was too weak and insecure.
Coal forests died and covered with new layers of sand and clay, but some trees survived due to the fact that the winged seeds with a solid shell were formed. Such seeds could spread faster, longer, and therefore for more distant distances. All this has increased their chances to find favorable conditions for germination or wait when they come.
Seeds were destined to revolutionize life on Earth at the beginning of the Mesozoic era. By this time, the sad fate of other coal vegetation was escaped two types of trees - coagovy and ginkgy. These groups began jointly settling Mesozoic continents. Without meeting competition, they spread from Greenland to the Antarctic, making the vegetation cover of our planet almost homogeneous. Their winged seeds traveled through mountain valleys, flew through lifeless rocks, germinated on sandy areas between stones and among alluvial gravel. Probably, to master new places were helped by small moss and ferns, who survived the change of climate on the planet at the bottom of the ravines, in the shadow of the cliffs and on the shores of the lakes. They feat down the soil with their organic residues, preparing her fertile layer for the settlement of larger species.
Mountain ridges and extensive plain sites remained naked. Two types of "pioneering" trees with covered seeds, settling on the planet, were tied to wet places, since their eggs fertilized by flagella, actively floating sperm, like moss and fern.
Many spore plants form disputes of different sizes - large megasives, giving rise to female gates, and small microspores, when dividing which moving spermatozoa. To fertilize the egg, they need to swim to it on water - at the same time there are quite enough rain and dew.
Sugarov and Ginkgo Megapar are not scattered by the parent plant, but remain on it, turning into seeds, but the sperm is movable, so dampness is needed for fertilization. External structure These plants, especially their leaves, also brings them closer with fernal ancestors. The preservation of an ancient way in fertilization in water with spermatozoids led to the fact that in spite of the relatively endless seeds, the continuous drought remained an insurmountable problem for these plants, and the conquest of sushi suspended.
The future of terrestrial vegetation was provided by the trees of another type, growing among the coagwomen and Ginkgo, but lost flavored spermatozoa. These were preserved to this day of Araucaria (genus Araucaria.), coniferous descendants of coal Cordates. In the era of coagists of Araucaria began to form huge amounts of microscopic pollen grains corresponding to microspores, but dry and dense. They were transferred to the wind to megasporam, more precisely to the seeds with eggs formed from them, and germinated with pollen tubes that were delivered to female gates fixed sperms.
Thus, pollen appeared in the world. There was no need for water for fertilization, and the plants rose to a new evolutionary step. The formation of pollen led to a colossal increase in the number of seeds, developing on each individual tree, and therefore, to the rapid spread of these plants. The ancient araucaria also acted and the method of resettlement, preserved in modern conifers, with the help of rigid winged seeds, easily diverted by the wind. So, the first conifers appeared, and with time and well all the well-known types of pine family.
Pines are formed two types of cones. Male Long OK. 2.5 cm and a diameter of 6 mm are grouped by the ends of the most upper branches, often beams in the top ten or more, so that a large tree may have several thousand. They dissipate pollen, sprinkling everything around with yellow powder. Women's cones are larger and growing on a tree below the male. Each scan of their shape resembles a scoop - wide outside and tapering to the base, which it is attached to a rustic axis of a bump. On the upper side of the scales closer to this axis openly there are two megasives, waiting for pollination and fertilization. The pollen grains departed by the wind fly inside the female cones, roll on the scales to the seeds and come into contact with them necessary for fertilization.
Suganov and Ginkgo did not stand competition with more progressive conifers, which, effectively dispel pollen and winged seeds, not only fastened them, but also mastered new, inaccessible to the sushi corners. The first coniferous dominants were a taxi (now they include, in particular, sequoia and marsh cypresses). By spreading around the world, these beautiful trees were last covered with all parts of the world with homogeneous vegetation: their remnants are found in Europe, North America, Siberia, China, Greenland, in Alaska and in Japan.
Coniferous, coagovic and ginkgov belong to the so-called. gamped plants. This means that their seeds are open on seed scales. Flower plants constitute a separated department: their seeds and developing the seeds are hidden from the external environment in the expanded base of the pestle, called the urging.
As a result, the pollen grain cannot reach directly the seeds. For merger, the Games and the development of the seed requires a completely new plant structure - flower. His male part is represented by stamens, female - pestles. They can be in the same flower or in different flowersEven by different plantswhich are in the latter case are called dwarm. Dochemny species include, for example, the outer, holly, poplar, willow, dotnical palm trees.
In order to occur in fertilization, the pollen grain should get to the pestper of the pestle - sticky, sometimes a crooked strait - and stick to it. The stil is distinguished by chemicals, under the action of which pollen grain germinates: a live protoplasm, leaving from under its solid shell, forms a long pollen tube that penetrates in a stroke, propagating the pestle into the stretched part (column) and achieving ultimately wound with Semyaps. Under the influence of chemical attractants, the kernel of the male game moves along the pollen tube to the seedness, penetrates into it through the tiny hole (micropyl) and merges with the core of the egg. So the fertilization occurs.
After that, the seed begins to develop - in a wet medium, abundantly supplied with nutrients, protected by walls of launch from external influences. Parallel evolutionary transformations are also known in the animal world: the outer fertilization, typical, say, for fish, is being replaced by internal, and the embryo mammals is formed not in the eggs pending in the outer medium, as, for example, in typical reptiles, and inside the uterus. The insulation of a developing seed from foreign influences allowed the flowering boldly to "experiment" with its form and structure, and this in turn led to an avalanche-like appearance of new forms of land plants, the diversity of which began to increase invisible in the previous epochs.
Contrast with viced is obvious. Their "naked", lying on the surface of the scales of the seeds, regardless of the type of plant, is approximately the same: the drop-shaped, coated with solid leather, to which the flat ward formed by the surrounding seed cells is sometimes attached. It is not surprising that for many millions of years, the form of gifts remained very conservative: pine, spruce, fir, cedar, teasers, cypress trees are very similar to each other. True, juniper, tissue and ginkgo seeds can be confused with berries, but this does not change the overall picture - the extreme uniformity of the common plan of the structure of the voted, values, type and painting of their seeds in comparison with the huge wealth of the forms of flowering.
Despite the poverty of information about the first stages of the evolution of the covered brushes, it is believed that they appeared by the end of the Mesozoic era, which ended about 65 million years ago, and at the beginning of the Cenozoic Era have already won the world. Ancient famous science Flower race - Claytonia. His fossil residues were found in Greenland and on Sardinia, i.e., it is likely that another 155 million years ago he was distributed as wide as a coagovy. Leaves U. Claytonia Painty-complex, like the current horse chestnuts and lupins, and the fruit of the berry-like diameter of 0.5 cm at the end of a thin fruit. Perhaps these plants were brown or green. Bright paints of flowers and fruits of coated bridges appeared later - in parallel the evolution of insects and other animals, which they were called upon to attract. Ya Berry Claytonia four-member; It can be distinguished by something resembling the residue of the stall.
In addition to extremely rare fossil residues, it is possible to obtain some idea of \u200b\u200bthe first flowering plants allow unusual modern plants combined by the rennet (gnetales). One of their representatives - the conifer (kind Ephedra.), occurring, in particular, in the deserts in the south-west of the United States; Outwardly, it looks like a few noble rods that depart from a thick stem. Another genus - Velvichia ( Welwitschia.) grows in the desert at the southwestern coast of Africa, and the third - Gnetum ( Gnetum) - Low shrub of Indian and Malay tropics. These three kinds can be considered "alive fossils", demonstrating possible ways to convert vicious plants into covered bridges. The coniferous coniferous appendens flowers: their scales are separated into two parts resembling petals. At Velvichia, there are only two wide tanning sheets up to 3 m long, absolutely not similar to the needles of conifers. Seeds of the opposite are equipped with an extra shell that makes them similar to bonuses of coated bridge. It is known that the coated bridges differ from the vote and in the structure of wood. In the oppression in it combines signs of both groups.
The viability and variety of plant world depends on the ability of species to settle. Parental plant is attached to one place all his life, therefore, his offspring should be found another. This task to master the new space was assigned to the seeds.
First, the pollen should get to the flower pestle of the same type, i.e. Pollination should occur. Secondly, the pollen should reach the seedwork, where the kernels of the male and women's weights are alive. Finally, the mature seed will have to leave the parent plant. The likelihood that the seed will germinate and shoot successfully arrives in a new place is an insignificant share of the percentage, so plants are forced to rely on the law of large numbers and dispel as much seed as possible. The last parameter is generally inversely proportional to their chances for survival. Compare for example coconut palm and orchids. Coconut palm has the largest seeds in the plant world. They are able to fly to the oceans indefinitely for a long time, while the waves will not throw them into mild coastal sand, where the competition of shoots with other plants will be much weaker than in the forest more often. As a result, the chances of getting along with each of them are quite high, and one mature palm tree without risk for kind brings only a few dozen seeds per year. Orchids, on the contrary, the smallest seeds in the world; In tropical forests, they are spread with weak air currents among high crowns and germinate in the wet cracks of the bark on the branches of trees. The situation is complicated by the fact that on these branches they need to find a special kind of fungus, without which germination is impossible: small seeds of orchids do not contain nutrient reserves and at the first stages of developing shoots are obtained from the mushroom. It is not surprising that in one fruit of miniature orchids several thousand such seeds.
Covenate plants are not limited to the formation of a variety of seeds as a result of fertilization: wound up, and sometimes other parts of the flowers are developing into unique, containing structure seeds - fruits. The ward can become a green bean that protects the seeds to their ripening, turn into a durable coconut, capable of making distant sea travel, in a juicy apple that will eat in a secluded animal, using the flesh, but not seeds. Berries and Kostyanki - Favorite Bird's delicacy: Seeds of these fruits are not digested in their intestines and fall into the soil together with excreta sometimes for many kilometers from the parent plant. Fruits are covered and fluffy, and the form of increasing the volatility of appendages they have much more diverse than pine seeds. The wing of the fruit of the ash is reminded of paddle, Ilma looks like a hats field, maplea steam fruits - double-straws - remind of soaring birds, the fetal wings are twisted at an angle to each other, forming a propeller.
These devices allow the flowering plants to be very efficient to use external factors to spread seeds. However, some types of extraneous assistance are not counting. So, the fruits are not a kind of catapult. A similar mechanism enjoy geraniums. Inside their long, the fruit passes the rod to which four to the pores are attached to time and the sash connected together - on top they hold firmly, the bottom is weak. During the ripening, the lower ends of the flaps are removed from the base, sharply twist to the top of the rod and spread the seeds. In America, a shrub of Tseanotus, the ward is turning into a berry, on the device close to the bomb with a clockwork. The juice pressure inside is so high that after ripening a fairly warm solar beam, so that its seeds live shrapnel scratch in all directions. Boxes of ordinary violets, drunk, burst and scatter around themselves seeds. The fruits of Gamamamelis are operating according to the principle of the Gaubi: so that the seeds fall away, they shoot them at a big angle to the horizon. At the Highlander of Virginsky in the place where the seeds are attached to the plant, the structure of the type of spring is formed, throwing ripe seeds. In the oily shell of the fetus, first swell, and then crack and so sharply compress that the seeds fly out through the slots. Arzutobium tiny due to hydraulic pressure Inside the berries pushes from them seeds as miniature torpedoes.
Envelopes in many seeds are provided with nutrients and do not suffer under the hermetic sheath of drying, and therefore they can wait for the favorable conditions for many months and even years: the dononon and alfalfa are 20 years old, in other legumes - more than 75, in wheat, barley and oats - to ten. Good viability is characterized by the seeds of weeds: at sorrel Curchaez, the cowboy, the mustard of the black and mountain of the list they germinate, laying in the ground of half a century. It is believed that 1.5 tons of sorting species seeds are buried on 1 hectare of conventional agricultural soil, which are only waiting for cases to be closer to the surface and give shoots. Seeds of cassia and lotus retain the germination of the centuries. Record for viability is still kept by the lotus seeds of the nuts, discovered several years ago in the bottom Ile of one of the dried lakes in Manchuria. The radiocarbon method found that their age is 1040 ± 120 years.
400 million years ago, the sea and oceans occupied a huge part of the earth's surface of our planet. The first living organisms arose in an aquatic environment. They were mucus particles. After several millions of years, these primitive microorganisms have a green color. In appearance, they began to resemble algae.
Climatic conditions have favorably affected the growth and reproduction of algae. Over time, the surface of the Earth and the bottom of the oceans was subjected to changes. There were new main students, the old were disappeared under water. The earth is actively changed. These processes led to the fact that water appeared on the site of the earth's surface.
Departing, marine water fell into crevices, depressions. They sworn, they were filled again with water. As a result, those algae who were on the seabed were gradually moved to the earth's surface. But since the process of the drainage took place very slowly, during this time they adapted to new habitat on earth. This process took place throughout a million years.
The climate at that time was very wet and warm. He contributed to the transition of plants from marine life to ground. Evolution led to the complication of the structure of various plants, algae also changed. They gave rise to the development of new earth plants - plyphitis. In appearance, they resembled small plants that were placed near the shores of lakes rivers. They possessed the stem, which was covered with small bristles. But, like by algae, the pylofs had no root system.
Ferns occurred from psulifitis. The psiliefs themselves 300 million years ago ceased to exist.
The wet climate and a large amount of water led to the rapid spread of different plants - ferns, horsages, plane. The end of the coal period was marked by changing the climate: it became more dry and cold. Huge ferns began to dy up. The remains of dead plants rotted and turned into a stone coal, which people then heated their homes.
Ferns on the leaves lay seeds that were called the vote plants. From gigantic ferns, modern pines, ate, fir, which are called gone plants occurred.
Ancient ferns disappeared with climate change. Cold climate ruined their gentle sprouts. They were replaced by seed ferns, which are called the first viced plants. These plants perfectly adapted to the new conditions of dry and cold climate. This type of plant has the reproduction process did not depend on the water, which is in the external environment.
130 million years ago various shrubs and herbs arose on Earth, whose seeds were in the surface of the fruit. They were called coated plants. Over the course of 60 million years, coated plants live on our planet. These plants have practically not changed since then to the present day.
We, contemporaries, quite a bit known about the first representatives of the plant world. Unfortunately, there are few of their fossil residues. However, scientists using fossil imprints left by ancient plants, still restored their appearance, and also considered the features of the structure of plants that became the first
Science, which studies the features of the structure and vital activity of fossil plants, is called "Paleobotan". It was Paleobotanians who are searching for answers to the questions of the origin of the plant world.
The first plants on Earth multiplied with the help of a dispute. Among the modern representatives of the flora also have disputes. According to the classification, all of them are combined into one group - "Higher Spore Plants". They are represented by rhinofitis, zosterophylaphites, trimesrophitis, psychephyphyphyt, briefites (mugh), lycopeodiophytes (plauenoid), equizetophytes (horstopholes) and polyptodiophytes (fern). Among these departments, the first three are completely extinct, and in the composition of others there are both extinct groups and now existing groups.
The first terrestrial plants were the representatives of the flora, who mastered the land of about 450 million years ago. They grown close to various reservoirs or in places of shallow water, for which it was characterized by periodic sleeve and dried.
All plants that have mastered land, there is a general sign. This is the separation of the body into two parts - overhead and underground. Such a structure was characteristic of rhinofitis.
The remains of ancient plants were first discovered in the second half of the XIX century on the territory of modern Canada. But for unexplained reasons, this discovery was not interested in botany specialists. And in 1912 near the Scottish village of Rain, the local village doctor found a few more petrified plants. He did not know that he was holding the remnants of the first terrestrial inhabitants in his hands, but, being very inquisitive, decided to thoroughly examine an interesting find. Making a cut, he discovered well-preserved remnants of plants. The stem was very thin, naked, and they were attached to the oblong form of the process (similar to the elongated balls) with very thick walls. Information about the find quickly reached Paleobotnikists, which found out that the remains found are the first land plants. There were doubts about the name of these ancient residues. But as a result, we decided to go on the simplest to go and unarked rhinofitis by the name of the village, about whom they were discovered.
The external structure of rhinofitis is very primitive. The body was branched to dichotomous type, that is, into two parts. Leaves and real roots, they have not yet had. Attachment to the soil was carried out with the help of rhizoids. As for the inner structure, it, on the contrary, was quite complex, especially compared to algae. So, there was a stute apparatus, with which the processes of gas exchange and evaporation of water were carried out. Due to the lack of their first plants on Earth were relatively small in height (no more than 50 cm) and the diameter of the stem (about 0.5 cm).
Paleobotanists believe that all modern land plants occurred from rhinofitis.
More likely no than yes. The name "piliability" really appeared in 1859. This American paleobotanist Dawson called so one of the found plants. He chose this particular option, since in the translation of this word means "bare plant". Up until the beginning of the 20th century, psulifitis was called the genus of ancient plants. But according to the results of subsequent revisions, this genus ceased to exist, and the use of this name was unauthorized. At the moment, the most fully described genius gives the name of the entire department of the oldest representatives of ground flora. Consequently, the first terrestrial plants were rhinofitis.
Presumably, the first terrestrial plants were Cuxony and Riland.
One of the most ancient representatives of the flora was Cuxonia, which had a form of a small coastal height of no more than 7 cm. A favorable environment of growth for her was marsh lowlands. The fossil remnants of Cuxony and the species related to it are found on the territory of the Czech Republic, the United States of America and in some regions of Western Siberia.
Close by Rodation, Riland is much better studied than Cuxony. Her body was more massive: a plant could reach 50 cm in height, and the diameter of the stem is 5 mm. At the end of the stem, the dome was located in which there were disputes.
The ancient representatives of the rhodium gave rise to many plants of the tropics and subtropics. According to modern classificationThey are united into the psiliefs department. It is very small, because it includes about 20 species. For some signs, they are very similar to their ancient ancestors. In particular, those and others have an exemplary height of psilofitis ranges from 25 to 40 cm.
Until recently, Paleontologists found in sediments over 425 million years old only remains of primitive twilight arguments with a smooth shell. Such finds found in Turkey. They are believed to the upper ordovik. Found specimens could not shed light on information about the time of the occurrence of vascular plants, as they were single and it was completely incomprehensible for them, as specifically representatives of the plant species belonged to smooth disputes.
But not so long ago, in Saudi Arabia, reliable remains of a twillet dispute with an ornamented shell were found. It was determined that the age of the samples of the samples varies from 444 to 450 million years.
In the second half of the Ordovka, the current Saudi Arabia and Turkey was the northern part of the supercontinent apparently, and was the initial territory of the habitat of vascular plants. The long historical period they lived only in their "evolutionary cradle", while the planets were settled by representatives of primitive mossoids with their cryptospores. Most likely, massive resettlement of vascular plants began after the great glaciation, which occurred at the turn of the Ordovica and the Silour.
During the study of rhinofit, the so-called body theory appeared, which the German botanist Cimmermann created. It was revealed by the features of the structure of rhinofitis, which by that time were recognized as the first terrestrial plants. There were zimmerman and alleged ways of formation of important vegetative and reproductive organs of higher plants are shown.
According to the German scientist, the body of rhinofitis consisted of radially symmetric axes, the final sprigs of which Zimmerman called the Telosmi (from Greek. Telos - "End").
Evolutionary by body, has undergone numerous changes, became the main organs of higher plants: stems, leaves, roots, sporesophilles.
So, now you can definitely answer the question "What was the first terrestrial plants?". Today the answer is obvious. These were rhinofitis. They were the first to get on the surface of the Earth and became the progenitors of representatives of modern flora, despite the fact that their external and the inner structure was primitive.
Looking at your home cactus, I involuntarily wondered: "And how did the plants start your way on land? And when did it happen?" About this very interesting topic I would like to tell.
As you know, the whole earthly life originated in water. And plants - no exception. Somehow they were all the simplest algaeBut then the stage came when they began to germinate and on land.
And they started their exit to the surface they are at the end Silora (near 4 05-440 million years old ago), what in Paleozoic era. Then actively happened powerful mining processesresulting in annoyance and drying many seas. That is exactly what made some algae "go out" to the land.
The most first plants on the surface are psulifi. They had only a bare stem, which was attached to the ground with the help of special increases - rhizoids. The psiliefs themselves had a very simple structure, but they had branched stems with increased growths that kept spore.
Psiliefs preferred marsh and wet terrain, After all, they did not have a powerful root system for water extraction. Today it is believed that once such plants were swept away endless carpets on the naked surface of the Earth.
In addition, psofithis could be like very high(much more human growth) and very lowand tiny.
Separate mention is worth system of deviceswhich mastered plants for life on land. After all, they are very different from life under water. So, such difficulties could be called:
And many others. Such plants also needed to learn to exercise more sophisticated photosynthesis, fix in soiland get from it necessary minerals.
All these difficulties were overcome vegetable organisms. And evidence of this - our life on earth.
