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What happened to several mass extinctions in the history of the earth?
1, Precambrian

2. Welsh

3. Ordovician

4. Silurian

5. Devon

6. Early Carboniferous

7. Late Carboniferous

8. Permian. See PERMO-TRIASSIC

9. Triassic

10, Jurassic

1 1, Late Jurassic

12, Cretaceous

13, Cretaceous-Tertiary extinction

14, Eocene

15, Miocene

16, Late Ice Age

17, Modern World

18, Future World

19 and1500,000 years later.

After 202.5 million?

1, Precambrian: Late Precambrian supercontinent and "igloo" world (650 million years ago)

1 1 100 million years ago, the Rodinia supercontinent began to split. The world in the late Precambrian is very close to the present climate and is an "ice room" world.

2. CAMBRIAN: The Paleozoic began (56,543.8+400 million years ago).

For the first time in CAMBRIAN, a large number of hard-shelled organisms appeared. Shallow seas flooded the mainland. The supercontinent Gondwana began to form near the South Pole. The Iapetus Ocean expands between the ancient Laurentia (North America), the Baltic Sea (Northern Europe) and Siberia.

3. Ordovician: Ancient oceans separated the mainland (458 million years ago).

4. Silurian: The Paleozoic ocean closed and the continents began to collide (425 million years ago).

5. Devonian: The Age of Fish (390 million years ago)

In Devonian, the ocean closed in early Paleozoic, forming a "pre-Pangaea" continent. Freshwater fish migrate from the southern hemisphere to North America and Europe. Forests originally grew in ancient Canada near the equator. Plants grew in large numbers, forming coal in today's northern Canada, northern Greenland and Scandinavia.

6. Early Carboniferous: Pangu continent began to form in the Early Carboniferous (356 million years ago).

In the Early Carboniferous, the Paleozoic ocean between Europe, America and Gondwana closed, forming the Appalachian Mountains in Apara and the Variscan Mountains in Vilis. The Antarctic began to form an ice sheet, and quadruped vertebrates began to develop in the coal swamp near the equator.

7. Late Carboniferous: Great Coal Marsh Age (306 million years ago)?

In the Late Carboniferous, the continent consisting of North America and Europe collided with Gondwana in the south, forming the western half of Pangea. Most of the southern hemisphere is covered with ice, and a huge coal swamp is formed along the equator. Centered on the equator, Pangu continent extends from the South Pole to the North Pole, separating the ancient Mediterranean and the ancient ocean on the east and west sides.

8. Permian. See PERMO-TRIASSIC

The end of Permian: the greatest extinction since ancient times (255 million years ago)

In Permian, a huge desert covered the western Pan-continent. At the same time, reptiles spread all over the supercontinent. 99% of the creatures disappeared in the extinction event, marking the end of Paleozoic.

9. Triassic?

At the end of Triassic, Pangu continent was formed (237 million years ago).

Pangu supercontinent formed in Triassic allowed terrestrial animals to migrate from Antarctica to the North Pole. After the Permian-Triassic extinction, life began to diversify again. At the same time, warm water biota spread to the whole Tethys Ocean.

10, Jurassic?

Early Jurassic: Dinosaurs spread all over Pangea (65.438+95 million years ago)?

In the early Jurassic, Central Asia and South Asia began to form. The vast ancient Mediterranean separated the northern continent from Gondwana. Although Pangu is still intact, you can hear the rumble that the mainland began to split.

1 1, Late Jurassic: Pangu began to split (10.52 billion years ago).

In the middle of Jurassic, Pangu began to split. In the late Jurassic, the middle of the Atlantic Ocean was a narrow ocean, which separated Africa from eastern North America. East Gondwana began to separate from West Gondwana.

12, Cretaceous: a new ocean opened (94 million years ago)?

The South Atlantic opened in Cretaceous. India separated from Madagascar, accelerated northward and crashed into Eurasia. It is worth noting that North America is still connected with Europe and Australia is still a part of Antarctica.

The global climate in Cretaceous was warmer than it is now. Dinosaurs and palm trees appeared in the Arctic Circle, Antarctica and southern Australia. Although there may be some ice sheets in the polar regions in the early Cretaceous, there were no large-scale ice sheets throughout the Mesozoic. Cretaceous is a period of rapid basin opening. The rapid expansion of mid-ocean ridges has led to the rise of sea level.

13, Cretaceous-tertiary extinction: the end of the dinosaur era (66 million years ago)

Hicksulubo hit the earth. The impact of this comet with a diameter of 16 km led to global climate change and the extinction of dinosaurs and many other species. In the late Cretaceous, the ocean continued to widen, and India approached the southern edge of Asia.

14, Eocene Early Cenozoic: India began to attack Asia (50.2 million years ago).

50 million to 55 million years ago, India began to attack Asia, forming the Qinghai-Tibet Plateau and the Himalayas. Australia, which was originally connected with Antarctica, began to move rapidly northward at this time.

15, Miocene: modern structure of the world (14 million years ago)?

20 million years ago, Antarctica was covered with ice and snow, while the northern continent cooled rapidly. The world looks similar to modern times, but please note that Florida and parts of Asia are still under the ocean.

16, Late Ice Age: In the past 30 million years, the earth entered the igloo climate (18,000 years ago).

When the earth is in an "ice room" climate, both poles are covered with ice and snow. The polar ice sheet expands due to changes in the Earth's orbit (Milankovic cycle). The last polar ice sheet expansion occurred 18000 years ago.

17, Modern World: There are clearly defined climatic zones in today's world.

We have entered a new stage of continental collision and will eventually form a new Pangu supercontinent. The global climate is warming, because we are leaving the ice age and at the same time, because we are releasing greenhouse gases into the atmosphere.

The formation of the earth

The systematic scientific research on the origin and evolution of the earth began in the middle of the eighteenth century, and many theories have been put forward so far. It is generally believed that the earth, as a planet, originated from the primitive solar nebula 4.6 billion years ago. Like other planets, the earth has experienced some similar physical evolution processes such as accretion and collision.

The material that formed the primitive earth is mainly the original material of the nebula disk, and its components are mainly hydrogen and helium, accounting for about 98% of the total mass. In addition, there are solid dust and matter thrown out by the early contraction and evolution stage of the sun. During the formation of the earth, due to the differentiation of substances, light substances are constantly separated from volatile substances such as hydrogen and helium, and are taken out of the solar system by solar light pressure and substances thrown out by the sun. Therefore, only when heavy matter or earth matter is condensed can the original earth gradually form and evolve into today's earth. Mercury, Venus and Mars, like the Earth, may have been formed in a similar way. Because they are close to the sun, they retain more heavy matter. And Jupiter, Saturn and other outer planets, because they are far away from the sun, still retain more light matter. Although there are still many speculations about the formation of the primitive earth, most researchers agree with Mr. Dai Wensai's conclusion that after the formation of the nebula disk, due to the effect of gravity and the instability of gravity, the materials in the nebula disk, including the dust layer, formed many protoasteroids or planetesimals due to collision accretion, and then gradually evolved into planets, in which the earth was born. It is estimated that the time required for the formation of the earth is about 1 billion years to 1 billion years. Planets closer to the sun (terrestrial planets) take a short time to form, while planets farther from the sun take a long time to form, even reaching hundreds of millions of years.