Current location - Music Encyclopedia - Today in History - What is the history of biological evolution?
What is the history of biological evolution?
About 6.6 billion years ago, there was a big explosion in the Milky Way. After a long time of gluing, its fragments and loose matter formed the solar system about 4.6 billion years ago. As a member of the solar system, the earth was also formed 4.6 billion years ago. Then, the ice-cold nebula material released a lot of gravitational potential energy, which was converted into kinetic energy and heat energy, leading to an increase in temperature, and the radioactive heat energy of the elements inside the earth also increased, so the original earth was in a molten state. In the process of high temperature earth rotation, the substances in it are differentiated, the heavy elements settle to the center and condense and nucleate, and the lighter substances constitute the mantle and crust, and gradually the circle structure appears. This process takes a long time. The original crust appeared about 3.8 billion years ago, which is consistent with the age of most rocks on the surface of the moon.

The origin and evolution of life are closely related to that of the universe. The constituent elements of life, such as carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur, come from the evolution of elements after the Big Bang. The data show that the chemical evolution in the pre-biological stage is not limited to the earth, and the products of chemical evolution exist widely in the universe. In interstellar evolution, some biomolecules, such as amino acids, purines and pyrimidines, may be formed in interstellar dust or condensed nebulae, and then under certain conditions, biopolymers such as peptides and polynucleotides are produced on the planet surface. Through several transitional forms of pre-biological evolution, the most primitive biological system, that is, life with original cell structure, was finally formed on the earth. At this point, the evolution of life began, and countless complex life forms have been produced on the earth until today.

3.8 billion years ago, a stable land mass was formed on the earth, and various evidences show that the liquid hydrosphere is hot and even boiling. Some extremely thermophilic archaea and methanogens may be closest to the oldest life forms on earth, and their metabolic patterns may be chemical and inorganic autotrophs. 3.5 billion years ago, microorganisms in the Wallavo group in Western Australia may be the earliest evidence of life on earth.

The appearance of the primitive crust marks that the earth has entered the era of geological development from the era of astronomical planets, and life with primitive cell structure has gradually formed. However, for a long time, there were not many creatures. Until the Cambrian 540 million years ago, a large number of metazoa with shells appeared, so the geological age after the Cambrian was called Phanerozoic.

Archean [Pre-Sinian (65.438+08 billion years ago to 4.5 billion years ago)] and Proterozoic [Sinian (570 million years ago to 65.438+08 billion years ago)]

Archean is the oldest period in geological history. From a biological point of view, this is the initial stage of primitive life and biological evolution. There were few prokaryotes at that time, and only a few fossil records were left. From the abiotic point of view, Archean was a period of thin crust, steep geothermal gradient, intense and frequent volcanic-magmatic activities, widespread deformation and metamorphism of rock strata, lack of free oxygen in the atmosphere and hydrosphere, and formation of a series of special sediments. It is also a period of formation and growth of silicon-aluminum crusts and an important metallogenic period.

In the early Proterozoic, some relatively stable large-scale and thick continental plates appeared on the surface. Therefore, in terms of lithospheric structure, Proterozoic is more stable than Archean. The atmosphere in the late Early Proterozoic already contained free oxygen. With the increasing prosperity of plants and the strengthening of photosynthesis, the oxygen content in the atmosphere increased continuously. The middle and late Proterozoic algae plants flourished, which was obviously different from Archean.

Sinian is a unique stage of geological history at the end of Proterozoic. From the perspective of biological evolution, there is an important difference between Sinian and Proterozoic without reliable animal fossils, because it contains metazoan fossils without hard shells. However, compared with CAMBRIAN, which is rich in crustacean fossils, the fossils contained in Sinian system are not only monotonous, few in number but also very limited in distribution. Therefore, animal fossils cannot be used for effective biostratigraphic work. The most prominent feature of Sinian organisms is that there are many kinds of shelled metazoa in the later period, and a small number of shelled animals in the later period. Advanced algae flourished further, and some new types of micro-animals appeared. Stromatolites tended to flourish in the early Sinian, and the number and species suddenly decreased in the later period. From the structure of lithosphere, several large and relatively stable continental plates have appeared on the surface of Sinian, and typical caprock deposits have appeared on them, similar to Paleozoic. Therefore, Sinian can be regarded as a transitional stage between Proterozoic and Paleozoic.

Beginning of Paleozoic era

Age of algae and invertebrates

Cambrian (from 570 million years ago to the trilobite age of 565,438+0 million years ago)

Cambrian is the first period of Paleozoic, which started 540 million years ago and lasted 40 million years. Cambrian is the first great development period of biology. At that time, there were rich, diverse and advanced marine invertebrates and a large number of fossils were preserved, so we can study the situation of the biological world at that time, divide and compare the strata by biostratigraphy, and then study the development history of the organic world and the inorganic world.

The famous ones are the Early Cambrian Chengjiang Fauna in Yunnan and the Middle Cambrian Burgess Shale Biota in Canada. Marine invertebrates and seaweed dominated the Cambrian biological world. Many advanced invertebrates, such as arthropods, echinoderms, mollusks, brachiopods and graptolites, are representative. Among them, trilobites are the most important arthropods, followed by brachiopods. In addition, ancient cups, ostracods, soft-tongued snails, odontoids and nautilus are also very important. In addition to conodonts, there are many other representative higher chordates, such as Huaxia eel, Yunnan fish and Haikou fish in Chengjiang fauna in Yunnan, China, dermatophytes in Burgess shale in Canada, and duck scale fish in Upper Cambrian in the United States.

Ordovician (565.438 million years ago to 438 million years ago)

Primitive vertebrates appeared.

Ordovician is the second phase of Paleozoic, which started 500 million years ago and lasted 65 million years. Ordovician is one of the most extensive periods of transgression in geological history. In the platform area inside the plate, seawater is widely distributed, showing the extensive development of carbonate rocks in coastal shallow sea. In the active geosyncline area on the plate edge, it is a deep-water environment, forming thick shallow and deep-sea clastic deposits and volcanic eruption deposits. There was a large-scale ice age at the end of Ordovician, which was distributed in Africa, especially in North Africa, Argentina and Bolivia in South America, Spain and southern France in Europe.

The Ordovician was more prosperous than the Cambrian, and marine invertebrates developed unprecedentedly, among which graptolites, trilobites, nautilus and brachiopods were the most important, and corals, kelp, echinoderms, ostracods and bryozoa among arthropods began to appear in large numbers.

In the middle Ordovician, primitive vertebrate miscellaneous fish-star turtles and shrubs appeared in the Rocky Mountains in North America, and Australia in the southern hemisphere also appeared. Plants are still dominated by seaweed.

The age of naked ferns and fish

During the Silurian period (438 million years ago to 465.438 million years ago), terrestrial plants and jaws appeared.

Silurian is the last period of Early Paleozoic. This period began 435 million years ago and lasted for 25 million years. Silurian was once called Godland because it developed well on Godland Island in the Baltic Sea.

The third division of Silurian is remarkable. Generally speaking, transgression generally formed in the Early Silurian, peaked in the Middle Silurian, and regressed and uplifted in different degrees in the Late Silurian, showing a huge transgression cycle. In the late Silurian, the strong crustal movement, the closure of the ancient Atlantic Ocean and the collision of some plates led to the rise of some geosynclines, the great changes in paleogeography, the remarkable expansion of the continental area and the great evolution of the biological world, all of which marked a turning point in the historical development of the crust.

Compared with Ordovician, the biological characteristics of Silurian have further developed and changed. Marine invertebrates still play an important role in Silurian, but the species replacement and internal composition of each category have changed. For example, the graptolite retains the double graptolite, and the emerging single graptolite is also very prosperous; The internal structure of brachiopods has become more complex, such as five-chambered shellfish, gastropods and small-mouthed shellfish. Cephalopods and nautilus in mollusks decreased obviously, while bivalves and gastropods developed gradually. Trilobites began to decline, but spiders and ostracods developed in large numbers. Horseshoe crab, also known as "sea scorpion", is widely distributed in the late Silurian ocean. Coralli's further prosperity; Among echinoderms, the number of sea lilies decreased greatly, and Silurian sea lilies appeared in large numbers.

Among vertebrates, the further development of jaw-less class led to the emergence of jaw-toothed shield fish and spiny fish, which was an important event in the evolution of vertebrates. Fish began to conquer the waters, creating conditions for the great development of Devonian fish.

In terms of plants, except algae, gymnosperms first appeared in terrestrial plants at the end of Late Silurian, and plants finally began to develop from water to land, which was another important event in biological evolution.

Silurian:

Life is born in the ocean and grows in the ocean. In Silurian, more than 400 million years ago, there were many kinds of life in the waters, with plants developing into macroalgae and animals developing into lower vertebrate fish. Life on land is very scarce, almost everywhere is Tongshan Tuling, a desolate place. Finally, due to the violent movement of the earth's crust, there is a general regression phenomenon on the earth's surface, many waters have become land, and some mountains have risen from the seabed. The great changes in the ocean have had a great impact on the creatures in the water.

Round-billed fish is very similar to fish, but it lacks paired pectoral fins and ventral fins, especially the jaws on the mouth, so it is also called "jawless". The ancient jawless species were all "soft-shelled turtles" covered with hard bones. After the appearance of Ordovician, the ancient jawless class appeared in Silurian. However, because they have no jaws and their lifestyles are backward, they can only feed on food mixed in the water flowing into China. Therefore, in the competition for survival, they can't compete with the emerging jaw fish and are declining day by day.

Devonian Fish Age (46.5438 billion years ago to 360 million years ago)

Devonian is the first period of Late Paleozoic, which started 4,654,380+0 million years ago and lasted about 55 million years. Devonian paleogeography changed greatly in early Paleozoic. It is manifested in the expansion of land area, the development of continental strata and the great changes of biological appearance. With the unprecedented development of terrestrial plants and fish-shaped animals, amphibians began to appear, and the composition of invertebrates also changed significantly.

Brachiopods developed rapidly in Devonian, and Siphidae, born in Silurian, became an important fossil in Devonian. In addition, perforated shellfish, twisted shellfish, foraminifera and small mouth shellfish are also very important in the division and correlation of Devonian strata.

Foam corals and double-banded corals are quite prosperous. The Devonian was dominated by foam type, and the coral with double belts began to rise; In the Middle Devonian and Late Devonian, the double-banded corals dominated.

Nautilus is greatly reduced, and Poseidon stone among ammonites and ammonites is flourishing.

Most straight graptolites are extinct, and a few represent single raptolites still existing in Devonian.

Zhujieshi began in Ordovician, reached its peak in Devonian and died out at the end of Devonian. Among them, thin-shell tower is the most prosperous, and bare-shell tower is also very important.

Conodonts evolved into Devonian and entered a peak of development, characterized by a large number of platform molecules.

Insect fossils were first discovered in Devonian.

Devonian is a period when vertebrates fly over and develop, and fish are quite prosperous and all kinds of fish appear, so Devonian is called "the age of fish". There were many jawless fish in Devonian, and shield fish flourished in the middle and late Devonian. They have primitive jaws, developed lateral fins and curved tails.

Devonian gymnosperms are developed, and there are a few Lycopodium plants, mostly herbaceous, with simple morphology and small individuals. Middle Devonian gymnosperms are still dominant, but primitive Lycopodium plants are more developed, and primitive wedge-leaved plants and the most primitive true ferns have appeared. When the late Devonian came, gymnosperms were on the verge of extinction, lycopodium continued to flourish, joint ferns and primitive wedge-leaf plants developed, and new true ferns and seed ferns began to appear.

Enter the era of ferns and amphibians.

The Age of Carboniferous Amphibians

The Carboniferous began about 355 million to 295 million years ago and lasted for 60 million years. In Carboniferous, the land area was increasing, and terrestrial organisms were unprecedentedly developed. At that time, the climate was warm, humid and swampy, and a large area of forests appeared on the mainland, which created favorable conditions for the formation of coal.

Carboniferous was a very active period of crustal movement, so great changes have taken place in paleogeography. During this period, the phenomenon of climate differentiation is very obvious. The northern ancient continent is a warm and humid coal-accumulating area, and Gondwana continent is a cold continental glacial sedimentary environment. Climate zoning leads to the formation of geographical zoning of animals and plants.

Compared with Devonian, the marine invertebrates in Carboniferous changed significantly. Corals and brachiopods are still the main benthos. Among zooplankton and zooplankton in the late Early Carboniferous, new species appeared, ammonites were still flourishing, and trilobites were mostly extinct in Carboniferous, leaving only a few genera and species.

Insects first discovered in Devonian flourished in Carboniferous, and more than 65,438+0,300 species were known in Carboniferous and Permian. Terrestrial vertebrates further flourished, and amphibians dominated. In the early Early Carboniferous, amphibians flourished, mainly cephalopods (also known as teeth) and crustaceans flourished.

The plant appearance of Early Carboniferous is similar to that of Late Devonian, and ancient pteridophytes continue to grow, but they can only adapt to the environment of coastal lowlands. The late Carboniferous plants developed further, and besides arthropods and lycopodium, true ferns and seed ferns also began to develop rapidly. Suaeda salsa is a tall tree in gymnosperms and has become one of the important raw materials for coal production.

Important coal-forming period of Permian

Permian is the last period of Paleozoic and an important coal-forming period. The Permian started about 295 million years ago and lasted for 250 million years, lasting 45 million years. The Permian crustal movement was active, and the relative movement between ancient plates intensified. Many geosynclines around the world are closed, and wrinkled mountain systems are formed one after another, and ancient plates are gradually spliced to form a United ancient continent (Pangu land). The further expansion of land area, the narrowing of ocean scope and the change of natural geographical environment have promoted the important evolution of the biological world and heralded the arrival of a new period in the history of biological development.

Permian is an important period of biological evolution. The main types of marine invertebrates are Zorro, Coral, Brachiopod and ammonite, but their composition has changed significantly. There are only a few representatives of trilobites in arthropods, and new developments have been made in gastropods and bivalves. At the end of Permian, all corals, amphibians, ostriches and trilobites were extinct. Brachiopods are greatly reduced, leaving only a few species.

Vertebrates developed to a new stage in Permian. Chondroid fish and bony fish have made new progress, and many new types of chondroid fish have appeared, and chondroscleroderma has developed rapidly. Amphibians flourished further. In Permian, Ceratosaurus made new development in reptiles. Zhonglong swims in rivers or lakes, represented by Zhonglong in Brazil and South Africa; Panlong was discovered in the Late Carboniferous and Early Permian. Theropoda is a mammal-like reptile in the middle and late Permian and Triassic, which is found all over the world.

The early Permian plant kingdom is similar to the late Permian, and ferns, Lycopodium, true ferns and seed ferns are still dominant. In the late Permian, gymnosperms such as ginkgo biloba, cycads, cycads and conifers appeared and began to take on the appearance of Mesozoic belt.

The Paleozoic era is over ... the Mesozoic era has begun! ! !

Mesozoic is the age of gymnosperms and reptiles!

The rise of Triassic reptiles and gymnosperms

Triassic is the first period of Mesozoic. From 250 million years ago to 203 million years ago, it lasted about 50 million years. After the Hercynian movement, many geosynclines were transformed into mountain systems, and the land area expanded, resulting in some inland basins in the platform area. This new paleogeographic condition has led to changes in sedimentary facies and biological world. Since Triassic, continental deposits have been widely distributed all over the world, especially in China and other parts of Asia. In paleoclimate, the early Triassic inherited the characteristics of drought at the end of Permian; After the middle and late period, the climate changed to moist heat, which led to coal-bearing deposition in Hongyan formation and the development of xerophytes to moist heat plants. At the same time, the geographical areas of plants are also differentiated.

In terms of biological changes, terrestrial reptiles have developed significantly compared with Permian. Representatives of ancient types (such as foraminifera and foraminifera) are basically extinct, and a large number of new types have emerged, some of which have moved to the sea to live. Primitive mammals also appeared at the end of Triassic. Due to the expansion of land area, freshwater invertebrates have developed rapidly, and marine invertebrates have taken on a new look. Ammonites, bivalves and foraminifera have become important categories to divide and compare strata, but if they are mixed with coral, they will be completely extinct.

Reptiles rose in Triassic, mainly composed of sawtooth, dinosaur and mammal-like reptiles. Typical early serrations showed many primitive features, limited to Triassic, and their overall structure was the ancestor model of later major reptiles and even birds. Dinosaurs first appeared in the late Triassic, and there are two main types: the older sauropods and the more evolved birds. Marine reptiles first appeared in Triassic. Because they adapt to life in the water, their bodies are streamlined and their limbs become paddle fins. Mammals and reptiles, also known as theropods, move their limbs to the ventral surface, so they are more suitable for walking on land.

Primitive mammals were first seen in the late Triassic and belonged to primitive mammals. The fossils they saw were all fragments of teeth and jaws.

In Triassic, the surviving late Permian ammonites flourished in large quantities. Most of the ammonites in the Middle and Late Triassic have developed decorative patterns, and many families are unique to Triassic. The rapid evolution of ammonites has created extremely important conditions for stratigraphic division and correlation.

The bivalve has also undergone obvious changes, and only a few late Paleozoic species continue to exist, resulting in many new species, and the number is considerable. Especially in the late Triassic, the structural types of some species and genera became complex, and the individuals were often large. Because the environment of Triassic is different from that of Paleozoic, non-marine bivalves gradually flourished.

Gymnosperms Cycas, Cycas, Nissan, Ginkgo biloba and conifers have developed rapidly since Triassic. Among them, various plants began to develop in the late Paleozoic, but they did not occupy an important position. The dry climate of Permian lasted until the early and middle Triassic, and plants began to flourish in the late middle Triassic. In the late Triassic, gymnosperms really became the main rulers of mainland plants.

Jurassic Reptiles and Gymnosperms Age

Jurassic is the second period of Mesozoic, which started 203 million years ago and ended 65,438+35 million years ago, and lasted 68 million years.

Some important events in the history of biological development have attracted people's attention. For example, dinosaurs became the rulers of land, pterosaurs and birds appeared, and mammals began to develop. Terrestrial gymnosperms have reached their peak. The bivalves, gastropods, arachnids, ostracods and insects of freshwater invertebrates have developed rapidly. Marine ammonites, bivalves and arrow stones are still important members, and the six-coral has not changed much from Triassic to Jurassic. Echinoderm sea urchin has occupied an important position since Jurassic.

Reptiles developed rapidly in Jurassic. The lazy tooth is extinct, and so is the ocean magic dragon. The evolutionary type of dinosaurs-two of the four main bird hips flourished in Jurassic, and flying reptiles glided in the sky for the first time. The first appearance of birds is one of the important changes in the history of animal development. Another kind of dinosaur, sauropod dinosaur, flourished in the Jurassic period: one was a carnivorous dinosaur, and the other was a huge herbivorous dinosaur. Marine reptiles, mainly ichthyosaurs and plesiosaurs, have become members of the marine environment that cannot be ignored.

Some of the most primitive mammals that appeared in the late Triassic were on the verge of extinction in the late Jurassic. In the early Jurassic, other early types of mammals, Polyodon, were newly produced, which were considered to be herbivorous and extinct in the early Cenozoic. Ancient mammals that appeared in the Middle Jurassic are generally considered as the ancestors of marsupials and placental mammals.

Cartilaginous scleroderma began to decline in Jurassic and was replaced by whole bone fish. The earliest true bone fish discovered in Triassic developed greatly in the late Jurassic, and the number increased, but the species was less.

The evolution degree of Jurassic ammonites was higher, mainly manifested in the complexity of suture lines, the diversity of shell ornamentation and shell shapes, which may be caused by ammonites adapting to different marine environments and various lifestyles. The Jurassic marine bivalves were abundant, and the non-marine bivalves also developed rapidly, which played an important role in the division and correlation of continental strata.

Jurassic is the heyday of gymnosperms. The development of cycads and ginkgo reached a peak, and conifers also occupied a very important position.

Reptiles and gymnosperms in Cretaceous turned from prosperity to decline.

Cretaceous is the last period of Mesozoic, which began 65.438+0.35 billion years ago and ended 65 million years ago, during which it experienced 70 million years. Both inorganic and organic fields experienced important changes in Cretaceous.

Severe crustal movement and land-sea changes led to great changes in the Cretaceous biological world. Many popular and dominant species (such as gymnosperms, reptiles, ammonites and arrowstones) declined and died out in the later period, and new angiosperms, birds, mammals, gastropods and bivalves all developed, indicating the arrival of a new stage of biological evolution-the new generation.

Reptiles reached their peak from late Jurassic to early Cretaceous and continued to occupy the ocean, land and sky. Birds are constantly evolving, and their characteristics are constantly approaching modern birds. Mammals developed slightly, and marsupials and primitive mammals with placenta appeared. Fish have been completely occupied by bony fish.

The most important marine invertebrates in Cretaceous are still ammonites, which are far more diverse than those in Jurassic in terms of shell size, shell shape, shell decoration and suture types. Marine bivalves, corals and foraminifera are also flourishing. Freshwater invertebrates are mainly bivalves, gastropods, ostracods and arachnids.

In the early Cretaceous, gymnosperms were still dominated by cycads, cycads, ginkgo biloba and conifers, and true ferns were still flourishing. Angiosperms, which rose from the late Early Cretaceous to the late Cretaceous, developed rapidly and gradually replaced gymnosperms and occupied a dominant position.

Mesozoic (Triassic-Jurassic-Cretaceous): [/b2] The Mesozoic in the history of the earth is called the "gymnosperms era". However, when the real terrestrial plants-gymnosperms-flourished, the real terrestrial vertebrates-reptiles-also developed. Therefore, from the animal's point of view, the Mesozoic Shuang can be called the "Reptile Age". Reptiles became the most prosperous vertebrates in Mesozoic. They have different shapes, systems and sides, and there are "dragons" everywhere. Developing to the ocean, such as ichthyosaurs; Towards the sky, like a flying dragon; To land, such as all kinds of dinosaurs. After the Early Triassic, more than 200 million years ago, some terrestrial reptiles returned to the ocean, and successively formed different ichthyosaurs and plesiosaurs, some of which were prominent animals in the ocean at that time. There are many kinds of reptiles, from crawling to flying, such as beak-billed dragon and pterodactyl. Going to heaven is not easy. It didn't go from crawling to flying overnight, but it took a long time, which was the result of variation and accumulation beneficial to Yu Feixiang from generation to generation.

A new generation has begun! ! It is the age of angiosperms and mammals! !

Tertiary angiosperm age

Mesozoic (Triassic-Jurassic-Cretaceous): the Mesozoic in the history of the earth, known as the "gymnosperms era." However, when the real terrestrial plants-gymnosperms-flourished, the real terrestrial vertebrates-reptiles-also developed. Therefore, from the animal's point of view, the Mesozoic Shuang can be called the "Reptile Age". Reptiles became the most prosperous vertebrates in Mesozoic. They have different shapes, systems and sides, and there are "dragons" everywhere. Developing to the ocean, such as ichthyosaurs; Towards the sky, like a flying dragon; To land, such as all kinds of dinosaurs. After the Early Triassic, more than 200 million years ago, some terrestrial reptiles returned to the ocean, and successively formed different ichthyosaurs and plesiosaurs, some of which were prominent animals in the ocean at that time. There are many kinds of reptiles, from crawling to flying, such as beak-billed dragon and pterodactyl. Going to heaven is not easy. It didn't go from crawling to flying overnight, but it took a long time, which was the result of variation and accumulation beneficial to Yu Feixiang from generation to generation.

Quaternary labor created mankind.

Quaternary is the latest stage of the earth's history, which began 654.38+75 million years ago. Quaternary includes Pleistocene and Holocene, and the boundary between them is marked by the end of the last ice age and the global warming, which is about 1 10,000 years ago.

The appearance of Quaternary biology is very close to modern times. The evolution of mammals is most obvious at this stage, and the emergence and evolution of human beings is one of the most important events in the Quaternary.

The evolution of quaternary mammals is mainly manifested in genera and species, not in the renewal of large categories. Mammals in the pre-Quaternary stage-early Pleistocene are still characterized by the prosperity and development of cloven-hoofed, long-nosed and new carnivores. The difference from Tertiary is that there are real elephants, real horses and real cows. In the late Pleistocene, some species and genera of mammals declined or became extinct. By the end of Holocene and Quaternary, the appearance of mammals was basically consistent with modern times.

A large number of fossil data prove that human beings evolved from ancient apes. The fundamental difference between apes and the earliest people is that people can make tools, especially stone tools. Labor from making tools makes human beings fundamentally different from all other animals, and labor creates human beings. Another main feature is that people can walk upright. It is generally believed that the time from ape to human is at least 1000? Ten thousand years ago.

Marine invertebrates in Quaternary are still dominated by bivalves, gastropods, small foraminifera and six-shot corals. Terrestrial invertebrates are still dominated by bivalves, gastropods and ostracods. Among other vertebrates, teleost fish and birds continue to prosper, while amphibians and reptiles have not changed much.

Since the mid-Quaternary, the appearance of higher terrestrial plants is basically consistent with modern times. Today's cold zone, temperate zone, subtropical zone and tropical flora are gradually formed due to the alternation of glacial and interglacial periods. Micro and ultra-micro phytoplankton are still very important for the division and correlation of marine strata.

Cenozoic era: The Cenozoic era since 70 million years witnessed the great development of angiosperms. Mammals can develop greatly in the Cenozoic because there are a large number of developed angiosperms as a solid material foundation. The earliest placental mammals were insectivores. Most of them are small animals that feed on insects, and modern hedgehogs are their descendants. They have "differentiated" many times in different natural environments and developed into more than 20 different groups, forming a great prosperity of placental mammals.

Detailed division of Cenozoic era (unit: million years)

Paleogene Paleocene 65-53

Eocene 53-36.5

Oligocene 36.5-23

Miocene 23-5.3

Pliocene 5.3- 1.8

Quaternary Pleistocene 1.8―0.0 1

Holocene 0.0 1- modern

The stage of crustal development on the earth

1

Archaean-Proterozoic

Weak crustal activity; Marine sediments are absolutely dominant; Some ancient plots were formed at the end of the period.

2

Sinian Period

Marine sediments are dominant; The ancient platform was formed.

three

Cambrian-Ordovician-Silurian

Caledonian movement and marine deposits still dominate; Finally, the Caledonian geosyncline folds and swells.

four

Devonian-Carboniferous-Permian

Hercynian movement, relative expansion of land; At the end of the period, many geosynclines rose, the northern continent united, and the southern continent began to disintegrate.

five

Triassic-Jurassic-Cretaceous

Yanshan movement, the disintegration of the southern continent and the extensive activities of the northern continent; The area around the Pacific geosyncline rises into mountains.

six

Tertiary Paleocene, Eocene, Oligocene, Miocene and Pliocene.

Himalayan orogeny, paleoplatform and paleofold are widespread; The ancient Mediterranean belt and the outer belt around the Pacific Ocean rise to mountains.

seven

Quaternary Pleistocene, Holocene-Neotectonic period

The difference fluctuates significantly and glaciers are widely distributed.

The development stage of the animal kingdom on earth

1 Archaean

The lowest primitive creatures came into being.

Cambrian-Ordovician-Silurian

The era of marine invertebrates

3 Devonian

Fish times

4 Carboniferous-Permian

Amphibian age

5 Triassic-Jurassic-Cretaceous

Reptile age

6 tertiary industry

Mammalian age

7 Quaternary

Human age

The development stage of the plant kingdom on the earth

1 Archaean

The lowest primitive creatures came into being.

2 Sinian-Cambrian-Early Ordovician

Age of seaweed

3 Early Ordovician-Carboniferous-Early Permian

Age of terrestrial spore plants

4 Early Permian-Triassic-Jurassic-Middle Cretaceous

Age of gymnosperms

5 Middle Cretaceous-Tertiary-Quaternary

Angiosperm age

The epidemic period of some creatures on the earth.

1 Earth astronomical period

2 Archaean Pre-Sinian

Seaweed, sponge

Ancient 3 yuan: Sinian algae and sponges.

Paleozoic: CAMBRIAN

Algae, sponges, brachiopods, trilobites, Ordovician: algae, sponges, corals, brachiopods, sea lilies, sea buds, starfish, trilobites, Silurian: algae, sponges, corals, brachiopods, sea lilies, sea buds, starfish, trilobites. Brachiopods, sea lilies, sea buds, starfish, trilobites, sand fish, scales, nautilus, Permian: algae, sponges, corals, sea lilies, trilobites, sand fish, scales and nautilus.

5 Mesozoic