The era of middle life is called. How long did our ancestors live: historical facts and opinions of scientists

The accumulated materials on the geological structure of the earth's crust and the development of life made it possible to divide its geological history into six eras and create a geological time scale - a geochronological scale.

Each era is divided into periods, a period into epochs, and epochs into centuries.

Archean era - the era of the beginning of life

Proterozoic era - the era of primary life

Riphean - era of early life

Paleozoic era of ancient life

Mesozoic - era of middle life

Cenozoic - the era of modern life.

The eras are united into two eons: Cryptose and Phanerozoic.

The Croptozoic era unites the Archean, Proterozoic and Riphean eras. This eon accounts for almost 4 billion years, or 5/6 of the entire geological chronology.

This is the time of the origin of life, the appearance of primitive single-celled organisms. Skeletal fauna is completely absent.

They are characterized by active tectonic activity, as a result of which the geological structure of the earth's crust was formed, the appearance of water and the first simplest forms of life, and the accumulation of the first thick strata of sedimentary rocks. First, the platforms of the northern hemisphere and the Australian were formed, later the Indian, South American, African and Antarctic. At the same time, the first geosynclines (folded mountains) took shape.

Geological formations of these eras are represented by igneous, ancient sedimentary and metamorphic rocks: crystalline schists, limestones, marbles, etc. In an unweathered state, these rocks are a good foundation and good building materials. They form the crystalline foundation of the Russian, West Siberian and other plains, and come to the surface in our country south of Voronezh, in Karelia, the Murmansk region, in Eastern Siberia, the Urals, Central Asia and Altai.

Other eras - Pleozoic, Mesozoic and Cenozoic - are combined into the Phanerozoic (approximately 570 million years). The Phaenerozoic is the most important stage in the geological history of the Earth, which is characterized by the emergence and widespread development of skeletal organisms, the flourishing of the organic world and the appearance of man.

Palaeozoic–Pz began approximately 525-570 million years ago and lasted about 340 million years. The Paleozoic era is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. When necessary, changes were introduced to the standard stratigraphic scale to reflect regional specifics. For example, in Europe there is a Carboniferous period, and in the USA there are two corresponding periods - the Mississippian and the Pennsylvanian.

The Paleozoic era is characterized mainly by a very warm and humid subtropical climate, which led to the formation of many rocks of organogenic origin. During this period, two major phases of mountain building occurred, accompanied by intense crushing of rocks. The first, Caledonian phase occurred in Scotland, Western Scandinavia, Greenland, and in Russia it is the Transbaikalia region. During the second, Hercynian phase, the Ural Mountains, Tien Shan, Altai, etc. were formed. During the era of rock formation, the tropical climate gave way to a sharp cooling, and during the era of the Hercynian phase, glaciation even occurred.

During the Paleozoic era, limestones, marls, and dolomites were formed in the seas, and clays, sands and sandstones were formed on the continents. In the last periods of the Paleozoic - Carboniferous and Permian - thick deposits of coal, limestone, sandstone, shale, as well as chemical sedimentary rocks - gypsum, anhydrite, rock salt - were formed. The rocks formed during this era contain many remains of fauna and flora. The forms were primitive and were very far from modern ones; these were spore plants and invertebrate animals, and subsequently extinct vertebrates.

Most rocks of the Paleozoic era can serve as a reliable foundation and be used as building materials.

Mesozoic era Mz (the era of middle life) began 190 million years ago and had a duration of about 125 million years, divided into three periods: Triassic, Jurassic and Cretaceous. The era is distinguished by a relatively warm, uniform climate and tectonic peace. Only in the Jurassic period did the Cimmerian phase of mountain building take place, as a result of which the formation of the Caucasus and Crimean mountains began. At the same time, a continental climate was observed, in which coals and clays were formed.

During the Mesozoic period, marine and continental sediments became equally widespread. Within the Russian plain, thick deposits of chalk, limestone, and clay formed. The possibilities of using rocks of the Mesozoic era for construction purposes are the same as during the Paleozoic period.

During this era, reptiles were very large in size. The fauna and flora were of a transitional nature - from ancient forms of the organic world to modern ones.

Cenozoic eraKz(the era of new life) began 65 million years ago. The flora and fauna are approaching modern forms, and man appears. The era is divided into three periods: Paleogene, Neogene and Quaternary. The first two periods are usually combined into one - tertiary. The Quaternary period takes only 1 million years and has been studied in most detail. It was at the beginning of the Quaternary period that man appeared.

The Cenozoic era is distinguished by different, sharply different climatic conditions. During the Paleogene period, the climate was warm, almost tropical; during the Neogene period, cooling was observed, which in the Quaternary period turned into the Ice Age with periodic glaciations. Glaciations covered a vast territory of northern Europe and Asia.

In the Cenozoic era, the so-called Alpine folding manifested itself very intensively, the formation of which began in the Jurassic period. In the Tertiary period, the formation of the Caucasus and Crimean mountains ended. At the same time, the ridges of North Africa, the Alps, the Carpathians, the Pamir Mountains, the Tien Shan, the Himalayas, the Kuril Islands, and Sakhalin-Kamchatka appeared. The Alpine orogeny phase has not yet ended.

In the Tertiary period, rocks of marine and continental origin were formed. Marine tertiary deposits - clays, limestones, shell rocks, etc. are located on the Black Sea coast and in other places. Continental tertiary deposits are ubiquitous.

The overwhelming majority of Quaternary rocks are continental deposits - loose rocks and rocks of organogenic origin. They are usually called Quaternary rocks or sediments in contrast to the earlier rocks, which I call bedrock. Marine Quaternary deposits are rare in Russia - on the coasts of the seas, north and east of the Caspian Sea and on the northern coast of the Black Sea. The composition and properties of these deposits are similar to tertiary ones. A special group among them are marine silts.

The thickness of Quaternary deposits ranges from several centimeters to tens and hundreds of meters. These rocks are less reliable as foundations than roots. Their properties vary widely and largely depend on genetic characteristics.

Bedrock is usually represented by rock and compacted sand and clay rocks, and among Quaternary sediments, loose formations, weakly cemented and cohesive, predominate.

Life on Earth began over 3.5 billion years ago, immediately after the completion of the formation of the earth's crust. Throughout time, the emergence and development of living organisms influenced the formation of relief and climate. Also, tectonic and climatic changes that occurred over many years influenced the development of life on Earth.

A table of the development of life on Earth can be compiled based on the chronology of events. The entire history of the Earth can be divided into certain stages. The largest of them are eras of life. They are divided into eras, eras into epochs, epochs into centuries.

Eras of life on Earth

The entire period of the existence of life on Earth can be divided into 2 periods: the Precambrian, or cryptozoic (primary period, 3.6 to 0.6 billion years), and the Phanerozoic.

The Cryptozoic includes the Archean (ancient life) and Proterozoic (primary life) eras.

The Phanerozoic includes the Paleozoic (ancient life), Mesozoic (middle life) and Cenozoic (new life) eras.

These 2 periods of life development are usually divided into smaller ones - eras. The boundaries between eras are global evolutionary events, extinctions. In turn, eras are divided into periods, and periods into epochs. The history of the development of life on Earth is directly related to changes in the earth’s crust and the planet’s climate.

Eras of development, countdown

The most significant events are usually identified in special time intervals - eras. Time is counted down in reverse order, from ancient life to modern life. There are 5 eras:

1. Archean.
2. Proterozoic.
3. Paleozoic.
4. Mesozoic.
5. Cenozoic.

Periods of development of life on Earth

The Paleozoic, Mesozoic and Cenozoic eras include periods of development. These are smaller periods of time compared to eras.

Palaeozoic:

• Cambrian (Cambrian).
• Ordovician.
• Silurian (Silurian).
• Devonian (Devonian).
• Carboniferous (carbon).
• Perm (Perm).

Mesozoic era:

• Triassic (Triassic).
• Jurassic (Jurassic).
• Cretaceous (chalk).

Cenozoic era:

• Lower Tertiary (Paleogene).
• Upper Tertiary (Neogene).
• Quaternary, or Anthropocene (human development).

The first 2 periods are included in the Tertiary period lasting 59 million years.

Table of the development of life on Earth

Era, period	Duration	Live nature	Inanimate nature, climate
Archean era (ancient life)	3.5 billion years	The appearance of blue-green algae, photosynthesis. Heterotrophs	The predominance of land over the ocean, the minimum amount of oxygen in the atmosphere.
Proterozoic era (early life)	2.7 billion years	The appearance of worms, mollusks, the first chordates, soil formation.	The land is a rocky desert. Accumulation of oxygen in the atmosphere.
The Paleozoic era includes 6 periods:
1. Cambrian (Cambrian)	535-490 Ma	Development of living organisms.	Hot climate. The land is deserted.
2. Ordovician	490-443 Ma	The appearance of vertebrates.	Almost all platforms are flooded with water.
3. Silurian (Silurian)	443-418 Ma	Exit of plants to land. Development of corals, trilobites.	with the formation of mountains. The seas dominate the land. The climate is varied.
4. Devonian (Devonian)	418-360 Ma	The appearance of mushrooms and lobe-finned fish.	Formation of intermountain depressions. Prevalence of dry climate.
5. Coal (carbon)	360-295 Ma	The appearance of the first amphibians.	Subsidence of continents with flooding of territories and the emergence of swamps. There is a lot of oxygen and carbon dioxide in the atmosphere.
6. Perm (Perm)	295-251 Ma	Extinction of trilobites and most amphibians. The beginning of the development of reptiles and insects.	Volcanic activity. Hot climate.
The Mesozoic era includes 3 periods:
1. Triassic (Triassic)	251-200 million years	Development of gymnosperms. The first mammals and bony fish.	Volcanic activity. Warm and sharply continental climate.
2. Jurassic (Jurassic)	200-145 million years	The emergence of angiosperms. Distribution of reptiles, appearance of the first bird.	Mild and warm climate.
3. Cretaceous (chalk)	145-60 million years	The appearance of birds and higher mammals.	Warm climate followed by cooling.
The Cenozoic era includes 3 periods:
1. Lower Tertiary (Paleogene)	65-23 million years	The rise of angiosperms. The development of insects, the emergence of lemurs and primates.	Mild climate with distinct climatic zones.
2. Upper Tertiary (Neogene)	23-1.8 million years	The appearance of ancient people.	Dry climate.
3. Quaternary or Anthropocene (human development)	1.8-0 Ma	The appearance of man.	Cold weather.

Development of living organisms

The table of the development of life on Earth involves division not only into time periods, but also into certain stages of the formation of living organisms, possible climate changes (ice age, global warming).

• Archean era. The most significant changes in the evolution of living organisms are the appearance of blue-green algae - prokaryotes capable of reproduction and photosynthesis, and the emergence of multicellular organisms. The appearance of living protein substances (heterotrophs) capable of absorbing organic substances dissolved in water. Subsequently, the appearance of these living organisms made it possible to divide the world into plant and animal.

• Mesozoic era.

• Triassic. Distribution of plants (gymnosperms). Increase in the number of reptiles. The first mammals, bony fish.
• Jurassic period. The predominance of gymnosperms, the emergence of angiosperms. The appearance of the first bird, the flourishing of cephalopods.
• Cretaceous period. Distribution of angiosperms, decline of other plant species. Development of bony fishes, mammals and birds.

• Cenozoic era.
  • Lower Tertiary period (Paleogene). The rise of angiosperms. Development of insects and mammals, appearance of lemurs, later primates.
  • Upper Tertiary period (Neogene). The formation of modern plants. The appearance of human ancestors.
  • Quaternary period (Anthropocene). Formation of modern plants and animals. The appearance of man.

Development of inanimate conditions, climate change

The table of the development of life on Earth cannot be presented without data on changes in inanimate nature. The emergence and development of life on Earth, new species of plants and animals, all this is accompanied by changes in inanimate nature and climate.

Climate Change: Archean Era

The history of the development of life on Earth began through the stage of the predominance of land over water resources. The relief was poorly outlined. The atmosphere is dominated by carbon dioxide, the amount of oxygen is minimal. Shallow waters have low salinity.

The Archean era is characterized by volcanic eruptions, lightning, and black clouds. The rocks are rich in graphite.

Climatic changes in the Proterozoic era

The land is a rocky desert; all living organisms live in water. Oxygen accumulates in the atmosphere.

Climate Change: Paleozoic Era

During various periods of the Paleozoic era the following occurred:

• Cambrian period. The land is still deserted. The climate is hot.
• Ordovician period. The most significant changes are the flooding of almost all northern platforms.
• Silurian. Tectonic changes and conditions of inanimate nature are varied. Mountain formation occurs and the seas dominate the land. Areas of different climates, including areas of cooling, have been identified.
• Devonian. The climate is dry and continental. Formation of intermountain depressions.
• Carboniferous period. Subsidence of continents, wetlands. The climate is warm and humid, with a lot of oxygen and carbon dioxide in the atmosphere.
• Permian period. Hot climate, volcanic activity, mountain building, drying out of swamps.

During the Paleozoic era, mountains were formed. Such changes in relief affected the world's oceans - sea basins were reduced, and a significant land area was formed.

The Paleozoic era marked the beginning of almost all major oil and coal deposits.

Climatic changes in the Mesozoic

The climate of different periods of the Mesozoic is characterized by the following features:

• Triassic. Volcanic activity, climate is sharply continental, warm.
• Jurassic period. Mild and warm climate. The seas dominate the land.
• Cretaceous period. Retreat of the seas from the land. The climate is warm, but at the end of the period global warming gives way to cooling.

In the Mesozoic era, previously formed mountain systems are destroyed, the plains go under water (Western Siberia). In the second half of the era, the Cordillera, the mountains of Eastern Siberia, Indochina, and partly Tibet were formed, and the mountains of Mesozoic folding were formed. The prevailing climate is hot and humid, promoting the formation of swamps and peat bogs.

Climate Change - Cenozoic Era

During the Cenozoic era, a general rise of the Earth's surface occurred. The climate has changed. Numerous glaciations of the earth's surfaces advancing from the north changed the appearance of the continents of the Northern Hemisphere. Thanks to such changes, the hilly plains were formed.

• Lower Tertiary period. Mild climate. Division into 3 climatic zones. Formation of continents.
• Upper Tertiary period. Dry climate. The emergence of steppes and savannas.
• Quaternary period. Multiple glaciations of the northern hemisphere. Cooling climate.

All changes during the development of life on Earth can be written down in the form of a table that will reflect the most significant stages in the formation and development of the modern world. Despite the already known research methods, even now scientists continue to study history, making new discoveries that allow modern society to learn how life developed on Earth before the advent of man.

Scientists studying the ancient world claim that our ancestors lived much shorter than modern humans. No wonder, because before there was no such developed medicine, there was no knowledge in the field of our health that allows a person today to take care of himself and predict dangerous diseases.

However, there is another opinion that our ancestors, on the contrary, lived much longer than you and I. They ate organic food and used natural medicines (herbs, decoctions, ointments). And the atmosphere of our planet was much better than it is now.

The truth, as always, is somewhere in the middle. This article will help to better understand what the life expectancy of people was in different eras.

The ancient world and the first people

Science has proven that the first people appeared in Africa. Human communities did not appear immediately, but in the process of a long and painstaking formation of a special system of relationships, which today are called “public” or “social.” Gradually, ancient people moved from place to place and occupied new territories of our planet. And around the end of the 4th millennium BC, the first civilizations began to appear. This moment became a turning point in the history of mankind.

The times of the primitive communal system still occupy most of the history of our species. This was the era of the formation of man as a social being and as a biological species. It was during this period that methods of communication and interaction were formed. Languages ​​and cultures were created. A person learned to think and make reasonable decisions. The first rudiments of medicine and healing appeared.

This primary knowledge became a catalyst for the development of humanity, thanks to which we live in the world that we have now.

Ancient human anatomy

There is such a science - paleopathology. She studies the structure of ancient people from remains found during archaeological excavations. And according to the data obtained during the research of these finds, scientists found that ancient people were sick just like us, although before the advent of this science everything was completely different. Scientists believed that prehistoric man was not sick at all and was completely healthy, and diseases appeared as a result of the advent of civilization. Thanks to knowledge in this area, modern scientists have found that diseases appeared before humans.

It turns out that our ancestors were also exposed to danger from harmful bacteria and various diseases. Based on the remains, it was determined that tuberculosis, caries, tumors and other diseases were not uncommon among ancient people.

Lifestyle of ancient people

But it was not only diseases that created difficulties for our ancestors. Constant struggle for food, for territory with other tribes, non-compliance with any hygiene rules. Only during the hunt for a mammoth, out of a group of 20 people, about 5-6 could return.

Ancient man completely relied on himself and his abilities. Every day he fought for survival. There was no talk of mental development. The ancestors hunted and defended the territory in which they lived.

Only later did people learn to collect berries, roots, and grow some grain crops. But it took a very long time for humanity to get from hunting and gathering to the agrarian society that marked the beginning of a new era.

Lifespan of primitive man

But how did our ancestors cope with these diseases in the absence of any medications or knowledge in the field of medicine? The very first people had a hard time. The maximum they lived to was 26-30 years old. However, over time, people learned to adapt to certain environmental conditions and understand the nature of certain changes occurring in the body. Gradually, the life expectancy of ancient people began to increase. But this happened very slowly as healing skills developed.

There are three stages in the formation of primitive medicine:

• Stage 1 – formation of primitive communities. People were just beginning to accumulate knowledge and experience in the field of healing. They used animal fats, applied various herbs to wounds, and prepared decoctions from ingredients that came to hand;
• Stage 2 – development of the primitive community and gradual transition to their collapse. Ancient man learned to observe the processes of the disease. I began to compare the changes that occurred during the healing process. The first “medicines” appeared;
• Stage 3 – collapse of primitive communities. At this stage of development, medical practice finally began to take shape. People have learned to treat certain ailments in effective ways. They realized that death can be deceived and avoided. The first doctors appeared;

In ancient times, people died from the most minor diseases, which today do not cause any concern and can be treated in one day. A person died in the prime of his strength before reaching old age. The average lifespan of a person in prehistoric times was extremely low. Everything began to change for the better in the Middle Ages, which will be discussed further.

Middle Ages

The first scourge of the Middle Ages was hunger and disease, which still migrated from the ancient world. In the Middle Ages, people not only starved, but also satisfied their hunger with terrible food. Animals were killed on dirty farms in complete unsanitary conditions. There was no talk of sterile preparation methods. In medieval Europe, a swine flu epidemic claimed tens of thousands of lives. In the 14th century, a plague pandemic that broke out in Asia wiped out a quarter of Europe's population.

Lifestyle of a medieval man

What did people do in the Middle Ages? The eternal problems remain the same. Diseases, the struggle for food, for new territories, but to this were added more and more problems that a person had when he became smarter. Now people began to fight wars for ideology, for ideas, for religion. If earlier man fought with nature, now he fought with his fellow men.

But along with this, many other problems also disappeared. Now people have learned to make fire, build reliable and durable homes for themselves, and began to observe primitive rules of hygiene. Man learned to hunt skillfully and invented new methods to simplify everyday life.

Life expectancy in antiquity and the Middle Ages

The wretched state in which medicine was in ancient times and the Middle Ages, many diseases that were incurable at that time, meager and terrible nutrition - all these are signs that characterize the early Middle Ages. And this is not to mention the constant strife between people, wars and crusades that claimed hundreds of thousands of human lives. The average life expectancy still did not exceed 30-33 years. Forty-year-old men were already called “mature husband”, and a man of fifty was even called “elderly”. Residents of Europe in the 20th century. lived to be 55 years old.

In ancient Greece, people lived on average 29 years. This does not mean that in Greece a person lived to be twenty-nine years old and died, but this was considered old age. And this despite the fact that at that time the first so-called “hospitals” had already been formed in Greece.

The same can be said about Ancient Rome. Everyone knows about the powerful Roman soldiers who served in the empire. If you look at the ancient frescoes, in each of them you can recognize some god from Olympus. One immediately gets the impression that such a person will live a long time and remain healthy throughout his life. But statistics say otherwise. The life expectancy in Rome was barely 23 years old. The average duration throughout the Roman Empire was 32 years. So Roman wars weren't all that healthy? Or are incurable diseases to blame for everything, from which no one was insured? It is difficult to answer this question, but data taken from more than 25,000 epitaphs on the tombstones of cemeteries in Rome indicate precisely these numbers.

In the Egyptian empire, which existed before the beginning of our era, which is the cradle of civilization, the Siberian Front was no better. She was only 23 years old. What can we say about the less civilized states of antiquity, if life expectancy even in ancient Egypt was negligible? It was in Egypt that people first learned to treat people with snake venom. Egypt was famous for its medicine. At that stage of human development, it was advanced.

Late Middle Ages

What about the later Middle Ages? In England, from the 16th to the 17th centuries, the plague raged. Average life expectancy in the 17th century. reached only 30 years of age. In 18th-century Holland and Germany, the situation was no better: people lived to an average of 31 years.

But life expectancy in the 19th century. began to slowly but surely increase. Russia in the 19th century was able to increase the figure to 34 years. In those days, people in England lived shorter lives: only 32 years.

As a result, we can conclude that life expectancy in the Middle Ages remained low and did not change over the centuries.

Modernity and our days

And only with the advent of the 20th century did humanity begin to equalize its average life expectancy. New technologies began to appear, people mastered new methods of curing diseases, the first medicines appeared in the form in which we are accustomed to seeing them now. The life expectancy rate began to increase sharply in the mid-twentieth century. Many countries began to develop rapidly and improve their economies, which made it possible to increase the standard of living of people. Infrastructure, medical equipment, everyday life, sanitary conditions, the emergence of more complex sciences. All this led to a sharp improvement in the demographic situation throughout the planet.

The twentieth century heralded a new era in the development of mankind. It was truly a revolution in the world of medicine and improving the quality of life of our species. Over the course of just half a century, life expectancy in Russia has almost doubled. From 34 years to 65. These numbers are amazing, because for several millennia a person could not increase his life expectancy by even a couple of years.

But the sharp rise was followed by the same stagnation. From the mid-twentieth century until the twenty-first century, no discoveries were made that radically changed ideas about medicine. Certain discoveries were made, but this was not enough. Life expectancy on the planet has not increased as rapidly as it did in the middle of the 20th century.

XXI Century

Humanity is faced with an acute question about our connection with nature. The ecological situation on the planet began to deteriorate sharply against the backdrop of the twentieth century. And many were divided into two camps. Some believe that new diseases appear as a result of our disregard for nature and the environment, while others, on the contrary, believe that the more we move away from nature, the more we extend our stay in the world. Let's consider this issue in more detail.

Of course, it is foolish to deny that without special achievements in the field of medicine, humanity would remain at the same level of knowledge of itself, its body at the same level as in the Middle Ages, or even later centuries. Now humanity has learned to treat diseases that have destroyed millions of people. Entire cities were carried away. Advances in the field of various sciences such as biology, chemistry, physics allow us to open new horizons in improving our quality of life. Unfortunately, progress requires sacrifice. And as we accumulate knowledge and improve technology, we inexorably destroy our nature.

Medicine and healthcare in the 21st century

But this is the price we pay for progress. Modern man lives many times longer than his distant ancestors. Today medicine works wonders. We have learned how to transplant organs, rejuvenate skin, delay the aging of body cells, and identify pathologies at the stage of formation. And this is only a small part of what modern medicine can offer every person.

Doctors have been valued throughout human history. Tribes and communities with more experienced shamans and healers survived longer than others and were stronger. States in which medicine was developed suffered less from epidemics. And now in those countries where the healthcare system is developed, people can not only be treated for diseases, but also significantly prolong their lives.

Today, the vast majority of the world's population is free from the problems that people faced before. There is no need to hunt, no need to make fire, no need to be afraid of dying from a cold. Today man lives and accumulates wealth. Every day he does not survive, but makes his life more comfortable. Goes to work, rests on weekends, has the opportunity to choose. He has all the means for self-development. People today eat and drink as much as they want. They don't need to worry about getting food when everything is in the stores.

Life expectancy today

Average life expectancy today is approximately 83 years for women and 78 years for men. These figures cannot be compared with those in the Middle Ages and especially in antiquity. Scientists say that biologically a person has about 120 years. So why are older people who turn 90 still considered centenarians?

It's all about our attitude to health and lifestyle. After all, the increase in the average life expectancy of a modern person is associated not only with improved medicine. The knowledge that we have about ourselves and the structure of the body also plays a big role here. People have learned to follow the rules of hygiene and body care. A modern person who cares about his longevity, leads a correct and healthy lifestyle and does not abuse bad habits. He knows that it is better to live in places with a clean environment.

Statistics show that in different countries where the culture of a healthy lifestyle is instilled in citizens from childhood, the mortality rate is significantly lower than in countries where this is not given due attention.

The Japanese are the longest living nation. People in this country have been accustomed to the right way of life since childhood. And how many examples of such countries are there: Sweden, Austria, China, Iceland, etc.

It took a long time for a person to reach this level and life expectancy. He overcame all the challenges that nature threw at him. How much we suffered from illness, from cataclysms, from the awareness of the fate that was in store for all of us, but we still moved on. And we are still moving towards new achievements. Think about the path we have taken through the centuries-old history of our ancestors and that their legacy should not be wasted, that we must only continue to improve the quality and duration of our lives.

About life expectancy in different eras (video)

During the Triassic there is a weakening
climatic zonation, smoothing
temperature differences Start of movement
continents. Giants are dying out
ferns, horsetails, mosses.
Gymnosperms reach their peak.
The emergence of the first bony fish. In the Triassic
the great war of two land forces began
reptilian and animal-like tribes.
Phytosaurus

The world of the Early Triassic 250 million years ago, the entire landmass of the Earth was united into the supercontinent Pangea, located in one

hemispheres.
The climate at this time was almost the same everywhere, without
such temperature fluctuations as in the modern world.
The area of ​​land that has become Africa in modern times
surrounded by both Americas (from the west), Europe (from the north) and
Antarctica (from the south). Modern Asian peninsula
Hindustan was one with Africa, separated
from Asia by a huge bay.

The shallow lagoons of the Triassic seas were home to a variety of marine reptiles, including Askeptosaurus (above),

resembling today's crocodiles, and Placodus, reaching 2.5
m in length and fed on shellfish.

The first mammals evolved from beast-like lizards

Aromorphoses of mammals:
four-chambered heart, loss of right
aortic arch;
warm-blooded;
long-term gestation of young
mother's body, embryo nutrition through
placenta;
more developed brain, larger
activity

Aromorphoses of mammals: (continued)

limbs under the body;
perfect lungs;
outer ear;
sweat glands;
differentiated teeth;
diaphragm;
feeding babies with milk;
hairline

Plants,
prevailing in
landscapes
Triassic period,
included
tree-like
ferns (top
left), cycad (in
center) and horsetails
(right), which arose in
Paleozoic era.
Fossilized
ferns (lower
drawing) were
found in rocks
Antarctica.

10. 220 million years ago, the landscape was dominated by shrubs interspersed with coniferous trees, reminiscent of modern ones, and huge

ginkgo plants (on the lower
The picture shows their fossilized leaves).

11.

The first gymnosperms appeared in
the end of the Paleozoic. In the Mesozoic they changed
tree ferns and horsetails, which
contributed greatly to drier conditions
climate.
Encephalartos, cycad tree

12. Ginkgo

GINKGO (Ginkgo biloba), the only one
extant species of the extensive order Ginkgoidae,
flourished during the Mesozoic era.

13. Gnetovye

GNETALES (Gnetales; gnetophytes, Gnetophyta),
order (according to other ideas, superorder
or class) extinct and living relicts
gymnosperms
Velvichia
Gnetum

14. Conifers

CONIFERAS, class of gymnosperms.
Currently widespread.
Mainly evergreen trees and
shrubs, usually with needle-shaped (needles)
or scaly leaves and unisexual
strobili (cones). OK. 50 births, approx. 600
species. Many conifers (pine, spruce,
larch, fir, etc.) - valuable
forest-forming species.

15.

In the Jurassic period, the climate, initially humid,
the end is dry. There's a movement going on
continents, formation of the Atlantic
ocean. The emergence of new groups of mollusks.
Seed ferns are dying out and
the first angiosperms appear
plants. Insects reach their peak and
reptiles. At the end of the period the appearance
the first bird - Archeopteryx.

16. Asteroceras obtusum is one of the species of ammonites that lived in the seas of the Jurassic period. At that time their shells were covered with much

more intricate
than in earlier species
patterns.
Some shells
grew to three or more
meters.
They ate large fish and
were dangerous predators

17. Development of mammals

Dimetrodon
megazastrodon
Lycenops Trinadoxone
the first warm-blooded and viviparous mammals,
similar to modern ones, appeared at the beginning of the Jurassic
period more than 180 million years ago

18. The middle of the era of dinosaurs (Jurassic period).

Dinosaurs flourished during the Jurassic period
(208-144 million years ago). It is named so because
that in the Jura Mountains, located in the territory
France and Sweden contain stones that
formed at this time.
Some dinosaurs from this period were
of impressive size, armed with plates and
spikes.
Among
them
meet:
allosaurus,
Archeopteryx, Brachiosaurus, Diplodocus, Stegosaurus and
other.

19. Allosaurus

Meaning
titles:
"Strange Lizard"
Size: 11 m long
Weight: 1.5 tons
Other data:
walked on two
legs, thick neck,
small, but
strong upper
limbs, claws
upper fingers and
lower
limbs, huge
teeth, strong legs,
strong tail, open at
USA
in 1869

20. Stegosaurus

Name meaning: "Roofing"
lizard"
Size: 9 m long
Weight: 6-8 tons
Other data: moved on
four legs, small head,
tiny brain, double on the back
a row of plates, a spiked tail,
toothless beak-shaped mouth, small
molars, opened in the USA in
1877
Stegosaurus

21. Dinosaurs dominated the land, water and air

Development
reptiles were coming
on the way
idioadaptations

22. One of the largest herbivorous dinosaurs of the Jurassic period is Diplodocus. The long neck allowed it to “comb” food

One of the biggest
herbivorous dinosaurs
Jurassic period diplodocus (Diplodocus).
The long neck allowed
him to “comb” food from
the tallest conifers
plants. It is believed that
Diplodocus lived
small herds and
ate shoots
trees.

23. Diplodocus holds an important place in the imagination of many British schoolchildren due to this impressive skeleton on display in

London Natural History Museum (there is a skeleton nearby)
Triceratops).

24. DISCOVERY OF ARCHEOPTERYX

The remains of Archeopteryx were found in
fine-grained limestones of southern Germany,
which in the 19th century widely used in
printing lithographs. When in 1860 the workers
quarry split one of the limestone slabs,
then they discovered the skeleton of a creature in the thickness of the layers,
resembled a bird. These remains were
investigated and described by German
paleontologist Hermann Mayer in 1861,
who named the found creature Archaeopteryx
lithographica.

25. Fossilized bones of Archeopteryx (top picture) allowed paleontologists to solve the problem of the appearance of this unusual bird

(round insert): this color is only a guess, but physical
the outlines are scientifically proven.

26. Aromorphoses of birds

four-chambered heart, loss of one of
two aortic arches (left);
warm-blooded;
greater brain development and more
challenging behavior;
caring for offspring.

27.

The Cretaceous period had a cool climate,
increase in the area of ​​the World Ocean and
new rise of sushi. They're going intense
mountain-building processes (Alps,
Andes, Himalayas). Parallel begins
evolution of flowering plants and insect pollinators. Carnivorous dinosaurs are becoming extinct
and large reptiles. Dying out in the seas
many forms of invertebrates and marine
lizards. Fittest
There are birds and mammals.

28. This is what the plain of modern Northwestern Europe might have looked like at the beginning of the Cretaceous period. Dinosaur in the background - herbivore

reptile, iguanodon. In the foreground are turtles and
crocodiles similar to modern ones.

29. The number and species diversity of mammals increased, animals appeared whose descendants are associated primarily with

one continent -
Australia. These are marsupials, the most primitive of today
living viviparous mammals and monotremes
(cloacal), or oviparous mammals.
Echidna from Australia is a representative of the unusual
groups of monotremes (or
cloacal) mammals.
Like reptiles, these
mammals
lay eggs.
Similar animals lived in
Australia is already 65 million years old
back.

30. During the transition from the Early to Middle Cretaceous period, the first flowering plants appeared. At the same time, evolution continued

huge herbivores
dinosaurs
Petrified leaf
magnolias (below),
found in rocks
Upper Cretaceous
period in Saxony
(Germany).
Reconstruction
plants (left)
shows that it
looked a lot like
Magnolia grandiflora
favorite
gardeners.

31. Aromorphoses of flowering plants

flower appearance and increase
pollination efficiency by different
ways;
double fertilization;
the ovule is hidden inside the ovary and
protected from external influences;
seeds develop inside the fruit;
greatest degree of differentiation
vegetative body.

32. Tyrannosaurus overtaking prey. The largest of the land predators, it reached 13 m in length and rose 5 m above the ground.

Its short front
limbs he probably
used for
to rise from
lying position.
Remains of a Tyrannosaurus
discovered in the USA.
Similar creatures lived
also on the territory
Canada and China.

33. By the end of the Cretaceous period, the fauna of the land had reached great diversity, and its representatives were perfectly adapted to

life in an even
and the favorable climate of this era. However
disaster was just around the corner
There are two types of ankylosaurs:
Euoplocephalus with
club-shaped tail and
thorny
Edmontia. These herbivores
lizards could successfully
protect yourself from predators
dinosaurs.

34. THE DEATH OF DINOSAURS One of the most significant events in the entire history of the Earth occurred ca. 65 million years ago. They became extinct at this time

some
large groups of vertebrates,
including dinosaurs as well
marine (mosasaurs,
plesiosaurs, pliosaurs and
ichthyosaurs) and flying
(pterosaurs) reptiles.
Other vertebrates: frogs,
lizards, crocodiles, snakes,
turtles, mammals and
survived the disaster.

35. conclusion

ANCIENTITY OF THE MESOZOIC ERA – 230 MILLION. YEARS,
DURATION – 165 MILLION. YEARS;
IN THE MESOZOIC REPELLERS ACCOMPLISHED HUGE PROGRESS
DIVERSITY FROM ANCIENT REPTILES OF THE TRIASS TO OURS
TURTLES AND HATTERIA LIVED TO THE DAYS;
AFTER THE STORMAL FLOWING OF DINOSAURS, THEY CAME
RAPID EXTINCTION;
MAMMALS CAME TO REPLACE THE SECOND
HALF OF THE CRETARY ARISED MARSPALIES AND PLACENTALS;
THE FIRST BIRDS APPEARED IN THE JURASSIC PERIOD;
DURING THE CRETACEOUS PERIOD THE FIRST FLOWERING APPEARED
PLANTS.

The Paleozoic era consisted of a whole revolution in the history of the Earth: a huge glaciation and the death of many animal and plant forms.

In the Middle Era we no longer find very many of the organisms that existed hundreds of millions of years before. Huge crayfish - trilobites, which were rampant in the seas of the Paleozoic, are disappearing, as if swept off the face of the Earth. Many echinoderms, entire families of sea urchins, starfish, sea lilies, etc. share their fate. Other echinoderms, however, remain in subsequent times, but they change greatly and develop in a completely new direction. Many coral species are disappearing. Great changes are also taking place in shellfish and fish. The land population is experiencing even more changes.

The heyday of tree ferns and horsetails has ended. Most of them did not survive the Paleozoic. Those species that still existed at the beginning of the Mesozoic era retained faint traces of their former splendor. They are found much less frequently, do not reach great heights, and often turn out to be completely short in stature. But coniferous and sago trees flourish, and after a while they are joined by numerous new breeds of flowering plants: palm trees become widespread. By its nature, the Mesozoic forest differs sharply from the forest of the ancient era. There was monotonous vegetation of gloomy tall trees. Here, coniferous and sago trees, palm trees, and behind them flowering plants give the earth's vegetation bright colors and cheerful tones. The fields are full of flowers.

The Mesozoic era is divided into three parts: the initial time is the Triassic period, the middle is the Jurassic period and later the Cretaceous period.

At the beginning of Mesozoic time, a dry but warm climate was established, then it became more humid, but continued to remain warm. The Mesozoic era lasted, according to many geologists, about 120 million years, with more than half of this time accounting for the last, Cretaceous period.

Already in the first of these periods, a change in the animal world was sharply noticeable. In place of the disappeared inhabitants of the seas, long-tailed crayfish arose in large numbers, similar to those that now live in the seas and rivers. On land, along with amphibians, many new animals appeared, developing from amphibians and called reptiles, or reptiles. We know that their origin from amphibians is connected with the need to conquer new land areas far from water.

In our time, very few of the reptiles, or scaly reptiles, as they are sometimes called, live. We can find relatively small lizards, turtles, snakes and crocodiles. In Mesozoic times, one could also see large and small lizards everywhere, similar to the inhabitants of our forests and rocks. Turtles also lived in those days; Most of them were found in the seas. But besides the rather harmless turtles and lizards, there was a terrible crocodile-like reptile, the distant descendant of which is the current crocodile. There were no snakes at all until almost the end of the Mesozoic.

In Mesozoic times there were many other breeds of reptiles that have now completely disappeared.

Of their remains, we are especially interested in strange skeletons in which the characteristics of reptiles are mixed with the characteristics of mammals, that is, those fur-covered animals whose females feed their young with milk (such as, for example, cows, pigs, cats, dogs and, in general, all carnivores , ungulates, rodents, monkeys, etc.). Amazing bones of beast-like reptiles have reached us, the structure of their legs and teeth was very reminiscent of mammals, which at that time did not yet exist on Earth. For its resemblance to animals, this breed received the name “beast-like”.

Among them is the famous foreigner, which was armed with sharp claws and powerful fangs, similar to the fangs of such predators as the lion and the tiger.

Inistrantzevia was found in 1901 during excavations of Permian deposits on the banks of the Northern Dvina.

One can imagine the devastation such predators caused among the population of Mesozoic forests and steppes. They contributed to the death of ancient amphibians, thereby clearing the way for the unprecedented development of reptiles, which we see in the Jurassic and Cretaceous times.

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