Science,English,and math 6th

【How does the earth become a planet in which a life can exist?】

《The Venus becomes a burning world because of the greenhouse effect》

As a result, amount of the steam evaporated from the sea increased in the atmosphere, so a strong greenhouse effect worked out by the steam, and the temperature rose again, to make matters worse, nothing could stop the circulation, at last the all the water evaporated from the sea.

Steam was broken down by the ultraviolet rays form the sun, and hydrogen was left, but it was lost in the outer space.

The Venus is near to the sun so much that the sea evaporated

【How does the earth become the planet in which a life can exist?】

《Coexistence between the ocean and continent prevents the greenhouse effect on the earth from working out》

Luminous intensity on the sun must have had influenced over the earth as well, but it has been known that the temperature on the earth doesn’t change so much from the past to the present time.

The temperature on the earth is stable because the continent and the sea exist at the same time.

The atmosphere on the earth in the beginning used to include carbon dioxide which is equal to the amount in the Venus at present.

【How does the earth become the planet in which a life can exist?】

《Coexistence between the ocean and the continent prevents the greenhouse effects on the earth from working out》

Even if there was under the dark sun, the sea didn't froze on account of the greenhouse effects.

If the composition in the air didn’t change, with the rise of the luminous intensity on the sun, the temperature went up higher and higher, but carbon circulated around the continent, atmosphere, in the sea.

As a result, the amount of the carbon dioxide in the atmosphere was controlled, and it prevented the….

【How does the earth become the planet in which a life can exist?】

《Coexistence between the ocean and the continent prevents the greenhouse effects on the earth from working out》

…controlling the amount of the carbon dioxide in the atmosphere prevents the temperature from going up.

Carbon dioxide is supplied in the atmosphere as volcanic gas, on the other hand, the carbon dioxide in the atmosphere is melted into rain water. When it rained, the land is eroded, the carbon dioxide connected with matter in the continent, and it was carried to the sea, after it was fixed to the rock in the seabed

【How does the earth become a planet in which a life can exist?】

《Coexistence between the ocean and the continent prevents the greenhouse effects on the earth from working out》

When the temperature goes up, the earth had a lot of rain, so the carbon dioxide is removed from the atmosphere, so it stops the temperature from going up.

《The Mars is small and becomes a cold and dry world》

The Mars has a cold and dry surrounding at present. The temperature on the surface of the ground is minus 60 degrees centigrade at present. Carbon dioxide which is a main ingredient in the atmosphere at Arctic…

【How does the earth becomes the planet in which a life can exist?】

《The Mars is small and becomes a cold and dry world》

Carbon dioxide which is a main ingredient in the atmosphere freezes at Antarctic and Arctic as dry ice in such the low temperature.

But the Mars used to be pretty warm in the beginning, and it has been thought the water was running on the surface of the ground in the Mars then.

When comparing it with the earth, it’s farther from the sun, but a mechanism of being stable on the weather functioned like the earth, the Mars must have been warm at present, but it isn’t. Why?

【How does the earth become a planet in which a life can exist?】

《The Mars is small and becomes a cold and dry world》

One of reasons is the Mars is so small that its inside becomes cold quickly.

As a volcanic activity wasn’t so active as the earth, the gas of greenhouse effective wasn’t supplied in the atmosphere, but as the ingredient in the atmosphere continued to be fixed on the surface of the ground, the temperature went down. It has been thought like that.

There is one more reason.

There is a possibility in the next. When a comet or an asteroid collide with the Mars, the atmosphere…

【How does the earth become a planet in which a life can exist?】

《The Mars is small and becomes a dry and cold world》

When colliding, the atmosphere was stolen from the Mars.

As the Mars has small gravitation, when the asteroid collided with it in high speed, a phenomenon that a part of the atmosphere is expelled to the outer space.

As a result, the atmosphere becomes thinner, so the surface on the ground may have been cold.

Anyway, the Mars is cold at present because it is small.

In other words, not only having appropriate distance from the sun, but having a proper size is important.

【How does the earth become a planet in which a life can exist?】

《The Mars is small and becomes a cold and dry world》

Those elements are important not only for existence on the sea but the birth and evolution on the life in the earth

【A life was born】

《The long drama to the humankind》

It was some four billion years ago when a life was born on the earth. It happened at the bottom of a dark sea. The life evolved slowly in a way of great variety for a long long time. After that, the humankind was born, and evolved miraculously.

《The stage on evolution of life moved from the sea to the land》

【A life was born】

《The stage on evolution of life moved from the sea to the land》

Creatures accomplished explosive a great evolution in Cambrian period five hundred seventy five million years ago

A number of kinds on creatures used to be no more than a few dozens until then, but it increased suddenly to some ten thousand kind all at once.

It is characteristic on the Cambrian period that there were lots of creatures of unheard of shape like the ones which were discovered at Burgess Shale バージェス頁岩 in Canada.

Devonian period four hundred million years ago is called the era of fish.

【A life was born】

《The stage on evolution of life moved from the sea to the land》

Typical creatures in Devonian period is Dunkleosteus which was a tremendous fish, it was eight meters, and Hemicyclaspis of which skin were as if it had been an armor.

When fish increased in the sea greatly, other creatures advanced into the land. At first vegetation, in the next insects spread over the new world of the land.

Plants released a large amount of oxygen and ozone layer was formed, so the surrounding where a life was maintained was ready.

After Icythyostega which belonged to amphibian 両生類 in…

【A life was born】

《The stage on evolution of life moved from the sea to the land》

After Icthyostega which belonged to the first amphibian went on shore, the stage on evolution moved from the sea to the land all at once. Reptiles, mammals, and birds were born one after another.

The Mesozoic era 中生代 was the time for dinosaurs which was big reptiles. The one of which length of the body reached no less than 50 meters, the other of which body was covered with armor-clad, and another which had a big horn or ornament around the neck. Dinosaurs evolved in a way of great variety.

【A life was born】

《The stage on evolution of life moved from the sea to the land》

But around sixty five million years ago, lots of creatures which inhabited the earth including dinosaurs then disappeared suddenly.

It is said it was caused by collision on a meteorite, or climate change by volcanic activity, but it has been unclear.

There was other creature which lived there quietly as if they had hidden behind the dinosaurs during the Mesozoic era 中生代. They got over the big accident and accomplish the propagation. It’s mamal.

《After dinosaurs became extinct, mammal achieved propagation》

【A life was born】

《After dinosaurs became extinct, mammals accomplished propagation》

Dinosaurs became extinct and a new era started. Mammal which continued to earn a bare living at the inner part in a forest divided into varied forms as if they had waited for the chance.

Then the climate was warm and wet, and forest developed over the large area on the ground. Animals who ate leaves flourished then. There were ones of which appearance resembles rhino, but they belonged to a group which was different from rhino.

There was an ancient horse of which size was a dog of middle size.

【A life was born】

《After dinosaurs became extinct, mammal achieved propagation》

The ancient horse ate leaves on trees.

The biggest mammal on land in the history appeared. The height on its shoulder was 4.5 meters.

But the climate became cold and cool in the whole earth, and dried climate spread, and grassy plain developed gradually, then primitive mammal became extinct, instead true herbivore 草食動物 which ate grass, or new type of mammal which was suitable for running around the grassy plain appeared.

Twenty million years ago, all the mammal were all present like at present.

【A life was born】

《After dinosaurs became extinct, mammal achieved propagation》

But the animals then had strange appearance we’ve never seen.

The ones which belonged to elephants had a tusk like a shovel or which turned downward. Those animals which had strange tusks swaggered on the land.

Those mammal advanced into the sky, sea, and land and flourished as if they had filled with the space caused by extinction by dinosaurs.

Then the ones which advanced into on the trees among a forest was the primates 霊長類 including a humankind.

《The humankind branched from ape and headed miraculous…》

【A life was born】

《The humankind branched from ape and headed miraculous way five million years ago》

When was the humankind born?

We can investigate when the ones which were closely related to us branched from the ape owing to analysis on DNA. It was five million years ago, according to the analysis.

On the other hand, how much is the origin on the humankind clear from an investigation of excavation on fossils?

It was Australopithecus which was called the ancient humankind until lately. It’s clear it did a bipedal walking from the shape on pelvis 骨盤 and remainder footprints.

【A life was born】

《The humankind branched from the ape and headed miraculous way five million years ago》

But the oldest fossil on the Australopithecus is four billion years ago. It passed a million years from the time it branched from the ape, according to the analysis on DNA.

We’ve desired ardently a discovery on the fossil which filled with the time of blank, and it was found out in 1992.

The fossil was the one belonged to four million four hundred thousand years ago. The unearthed teeth shows us it branched from the ape and it didn't pass time so much.

Whether or not it did…

【A life was born】

《The humankind branched from the ape and headed miraculous way five million years ago》

Whether or not it did bipedal walking is under investigation.

In 1995, other one was discovered and announced it also did the bipedal walking then.

When the excavation and investigation makes progress and the whole picture on the ancient humankind is clear, moreover other fossils before it is discovered, the moment when the humankind was born becomes clear.

The ancient humankind made a group made up with several people and lived there. Its food was a stem and fruits. It has been…

【A life was born】

《The humankind branched from the ape and headed miraculous way five million years ago》

It has been thought then the humankind was away from the forest and started to live on the grassy plain. The bipedal walking which is one of characteristic on the humankind was got then, it seemed that it couldn’t use a complicated tool like stone implement.

《Making a tool and using a fire…the future on people was open widely》

First Homo which is our direct ancestor appeared some two million four hundred million years ago. It’s Homo habilis. Though it was awkwardly done, they made...

【A life was born】

《Making a tool and using a fire…the future on people was open widely》

Though it was awkwardly done, they made a stone implement. The modern high technology started from the plain stone implement.

A primitive man appeared some one million seven hundred thousand years ago. If comparing with Australopithecus and Homo Habilis, the primitive man had a modern characteristics.

Capacity on brain was twice as big as Australopithecus and was two thirds as big as a man of today. Bipedal walking by them was perfect. Their stone implement was formed excellently.

Moreover they….

【A life was born】

《Making a tool and using a fire…the future on people was open widely》

Moreover they succeeded in getting fire. Making a fire was after that so much. When a field burned off, they probably happened to get the fire. Using the fire decided the evolution as person.

Homo erectus in the beginning was tall. As to an adult male, it was from 180 to 185 centimeters. The proportion on the body was slim, and both of hands and legs were long. It seems that they were slender like the people at arid area in tropical zone.

Their muscle developed so extremely that we can’t think it of.

【A life was born】

《Making a tool and using fire…the future on people was open widely》

There is high possibility that body hair disappeared and adjustment on body temperature was done efficiently by perspiration then.

Those various change was enable the primitive men to escape from Africa for the first time in the history of humankind. They spread over the Eurasia continent and became Javanese primitive men and Beijing primitive men until a million years ago.

《Neo man who was born in Africa, Before long the humankind spread over the earth》

Neo man including our direct ancestor was born in…

【A life was born】

《Neo man who was born in Africa. Before long the humankind spread over the earth》

Neo men including our direct ancestor were born in Africa some two hundred million years ago. It’s Homo sapiens.

It has been thought they formed racial characteristic, and spread all over the world in the next process.

After Neo men departed from Africa, they reached the Middle East a hundred thousand years ago and branched from Negroid to Caucasus.

The ones who advanced into Europe some thirty five thousand years ago were Cro-magnon.
They were ancestors of European people.

【A life was born】

《Neo man who was born in Africa. Before long the humankind spread over the earth》

Cro-magnon came across Neanderthal who were aboriginal people. Its unclear what’s happened between them then.

When Cro-magnon appeared, at the same time, Neanderthal disappeared.

On the other hand, the ones who went to south of Mt. Himalaya became an ancestor of Indian people. The ones who went to north of Mt. Himalaya adapted themselves to cold and cool climate in the ice age, and became Mongoloid.

Others who advanced into Southeast Asia went over the sea and reached Australia. They were…

【A life was born】

《Neo man who was born in Africa. Before long the humankind spread over the earth》

They were ancestors of aborigines in Australia.

In a newer time there were others who sailed out on the Pacific Ocean.

Mongoloid in East Asia continued to move for new lands still more. Then as the surface on the sea became lower because of the ice age, the straits of Bering became an overhead bridge.

It has been thought Mongoloid who went up north Siberia crossed the overhead bridge and reached American continent around thirteen thousand years ago.

After that the people who spread over…

【A new life was born】

《Neo man who was born in Africa. Before long the humankind spread over the earth》

After that the people who spread over the whole America rapidly became the ancestor on aborigines in America. They reached Fuego island which is the southernmost tip of America no more than in thousand years. At last the humankind spread over the whole earth.

【The great accident on the earth in the time on dinosaurs】

《Coral reef saved the earth from the crisis on global warming》

The earth was in uproar owing to unusual movement of the earth’s crust in the early part of Cretaceous.

【The great accident on the earth in the time of dinosaurs】

《Coral reef saved the earth from the crisis on global warming》

It was a hundred million years ago.

A tremendous volcano of which area was one fourth times as big as the U. S. A. appeared on a seabed then. The surface on the sea rose and no less than 60% of the land was submerged.

Volcanic activity which twice as violent as at present released a large amount of carbon dioxide, and greenhouse effect made the earth approach the crisis which would invite extinction on creatures.

But not only the earth and creatures got over the…

【The great accident on the earth in the time of dinosaurs】

《The coral reef saved the earth from the crisis on global warming》

But not only the earth and the creatures got over the situation with a marvelous team work but brought back petroleum to us the humankind as resource.

The author said he was going to create the drama on the Cretaceous 白亜紀 here, being based on the latest data.

A strange black mudstone formation was discovered in the layers of some hundred million years ago each seabed in the world one after another from 1972, with the result of Ocean Drilling Program.

【The great accident on the earth in the time of dinosaurs】

《What’s happened then?》

The black mudstone formation is rich in organic matter, and it has been thought it was sludge when accumulating. Except for special circumstance, the mud like that doesn’t accumulated.

Organic matter in the ocean originates from phytoplankton 植物プランクトン existing on the outer layer.

As the dead body on the plankton was dissolved by bacteria in the seawater at once, the organic matter doesn’t usually lay thick on the deep sea bed.

As to the environment in which the organic matter accumulates, it often…

【The great accident on the earth in the time of dinosaurs】

《What’s happened then?》

As to the circumstance in which organic matter accumulates, it often appears when there is big difference on density of the water between the outer layer and deep layer owing to difference on salty density.

Then circulation on the water stops, and mixture between the upper place and lower place is inactive. Then oxygen is dissolved and necessary for organic matter to be dissolved until then, but the dissolution uses up the oxygen, then the activity on the bacteria stops, as a result, the organic matters are…

【The great accident on the earth in the time of dinosaurs】

《What’s happened then?》

…as a result, the organic matters are left in the seabed as they were. The surrounding like that at present is the Black Sea. The organic matters are accumulated at the seabed in the Black Sea as sludge.

As there is such the little oxygen that it becomes a Dead Sea where none of creatures can live, except for specific creatures.

The black mudstone formation tells us that the Cretaceous 白亜紀 when the dinosaurs lived, the sea bed was the world of death where the sludge was accumulated in wide area. Why did…

【The great accident on the earth in the time of dinosaurs】

《What’s happened then?》

Why did it happen? What kind of world was the earth a hundred million years ago?

《The surface on the sea was higher by 300 meters in the Cretaceous》

The Cretaceous is famous for the time when the sea advanced into the land in geology, especially the sea invaded into inside stable continent deep like in the middle west of North America, North Africa, and the Middle East.

There is a steep cliff made with chalk layer in the Strait of Dover. The chalk layer is origin on the name of Cretaceous.

【The great accident on the earth in the time of dinosaurs】

《The surface on the sea was higher by 300 meters in the Cretaceous》

When the sea invaded, shells of creatures made up with calcium carbonate were accumulated. It’s the chalk layer.

As to the situation on the continent, it was different from at present. Panguage which was a supercontinent and existed two hundred million years ago divided, and the Atlantic Ocean started to expand.

A super ocean extended as if it had surrounded the Panguage. In the both place where Arctic and Antarctic are, there was continent, and it was warm then.

【The great accident on the earth in the time of dinosaurs】

《The surface on the sea was higher by 300 meters in the Cretaceous》

It was so warm that there weren’t any ice sheet then.

Considering distribution on layers inside land created by the sea, it has been estimated that the surface on the sea used to be higher by 300 meters than present time. Even if the ice in the pole melted, it has been thought it would rise dozens of meters at most.

The surface on the sea couldn’t have risen so high like 300 meters because the ice melted in the polar region.

Moreover there is no evidence that….

【The great accident on the earth in the time of dinosaurs】

《The surface on the sea was higher than present time by 300 meters in the Cretaceous》

Moreover there is no evidence that the amount of the seawater itself changed. What did happen then?

《Unusual volcanic activity in the seabed shook the earth greatly a hundred million years ago》

Matters of high temperature gushed out from the submarine ridge owing to convection of mantle, and it spread over both side of the submarine ridge as new seabed, and old seabed sank into the trench in the sea. It’s the sea floor spreading theory and…

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity on the seabed shook the earth greatly a hundred million years ago》

It’s the sea floor spreading theory and develops into plate tectonics.

Matter is melted and gushed out from the mantle and became magma, and the magma became cool and hard and formed the plate in the seabed. It leads to expansion on the seabed.

With the activity, the matter moved from the mantle to the earth’s crust, to the seawater, to the atmosphere, and it is carried to the mantle again by sinking the plate in the trench of the sea.

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity on the seabed shook the earth greatly a hundred million years ago》

The process continues immediate after the earth was born, and rules over on circulation on matters on the earth.

The speed of expansion on the seabed isn’t always regular. The speed on forming the earth’s crust in the sea was 1 and half as quick as the present time in the Cretaceous, from a hundred and twenty million to a hundred million years ago.

Besides it turned out the next thing. Lots of higher places like a seamount and plateaus…

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity on the seabed shook the earth greatly a hundred million years ago》

Lots of higher places like a seamount and plateau in the sea are made up with lava of basalt gushed out in the Cretaceous.

Ontong Java plateau was the biggest plateau among them. It was one fourth times as big as the U.S.A. Other seamount and plateau in the sea was gushed out a hundred million years ago. It took a million years. It was a quite short term with a geological point of view.

Considering the unusual volcanic activity on the…

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity on the seabed shook the earth greatly a hundred million years ago》

Considering the unusual volcanic activity on the inside oceanic plate, the speed of forming the earth’s crust on the seabed reached twice as quick at present time at least. Why was there active volcanic activity on the seabed? It has been unclear.

A way of thinking that an enormous convection boiled up from inside the earth is likely.

Not only the earth’s crust on the sea but volcanic activity on the land and arc island were active then.

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity in the seabed shook the earth greatly a hundred million years ago》

The amount of gushed out of the volcanic rock reached twice as much as average during ten million years in the past.

It means two significant fact.

The active forming earth’s crust and volcanic activity on the seabed made the seabed rise, and seawater overflowed and the seawater invaded into the land. It was a cause that the sea invaded into the land greatly in the Cretaceous.

In the next, the violent volcanic activity could have…

【The great accident on the earth in the time of dinosaurs】

《Unusual volcanic activity on the seabed shook the earth greatly a hundred million years ago》

…a large amount of carbon dioxide could have been released in the atmosphere then, and the carbon dioxide must have had influenced on the climate greatly by greenhouse effect.

《The earth became warm thanks to greenhouse effect by carbon dioxide in the Cretaceous》

It was warm clearly in Cretaceous. It has been estimated that there was no ice sheet on both polar region, and there was no difference…

【The great accident on the earth in the time of dinosaurs】

《The earth became warm on account of greenhouse effect by carbon dioxide in Cretaceous》

…there was no difference on temperature between the north and south. It was estimated from characteristic on fossil pf plants. How about the temperature on the seawater?

Roughly speaking,the seawater has been divided into surface water and deep water at present. Lots of deep water sank into deep layer from North Atlantic Ocean and Antarctic Ocean and it circulates until North Pacific Ocean. The circulation takes time from 1500 years to 1000 years

【The great accident on the earth in the time of dinosaurs】

《The earth became warm because of greenhouse effect by carbon dioxide in the Cretaceous》

The temperature on the deep water is around two degrees centigrade, and from low latitude to middle latitude, the difference on temperature of water between deep water and surface water is some 20 degrees centigrade.

It proved that the temperature on deep water from low to middle latitude in Cretaceous was higher than present time by 15 ℃, Lukewarm water is a great characteristic in the surrounding on ocean in Cretaceous.

How was the deep…

【The great accident on the earth in the time of dinosaurs】

《The earth became warm owing to greenhouse effect by carbon dioxide in the Cretaceous》

How was the deep water formed?

Circulation on the seawater is basically caused difference density on the seawater. The difference between the seawater is caused by difference on salty density and temperature.on the seawater.

In the time when the sea invaded into the land greatly, the place from subtropical zone to low latitude was covered with shallow sea. The area on the sea was four times as big as present time.

Evaporation from the…

【The great accident on the earth in the time of dinosaurs】

《The earth became warm on account of greenhouse effect by carbon dioxide in the Cretaceous》

Evaporation was active in the shallow sea, and was warm and had a high salty density. The density on the water was so big that it sank into the deep sea and formed the deep sea.

The situation resembles the Black Sea so much.

Layers of seawater develops by difference between salty density, and mixture between the upper place and lower place became inactive, as a result the sludge accumulated. The mystery on the black mudstone formation in…

【The great accident on the earth in the time of dinosaurs】

《The earth became warm thanks to greenhouse effect by carbon dioxide in the Cretaceous》

The mystery on the mudstone formation in the Cretaceous is solved like that.

The author said he was going to express the gist on the surrounding on the earth in the Cretaceous.

Then the earth was warm and the ice sheet didn’t develop in both polar region, so the temperature on the water was also warm., especially there was lukewarm seawater of high salty density in deep layer.

The surface on the sea was high, and about two thirds on the…

【The great accident on the earth in the time of dinosaurs】

《The earth became warm owing to greenhouse effect by the carbon dioxide in the Cretaceous》

The surface on the sea was high and about two thirds of the surface on the ground was submerged. Sludge accumulated at the seabed, and there was no oxygen.

The surrounding which was warmer and higher surface on the sea than present time caused by raising seabed because of lots of volcanic activity and greenhouse effect by releasing carbon dioxide.

《Coral reef and sludge saved the earth the crisis on the global warming and brought petroleum》

【The great accident on the earth in the time of dinosaurs】

《Coral reef and sludge saved the crisis on global warming and brought us petroleum》

If the carbon dioxide continued to release as it was, the earth may have fallen into crisis which brought extinction on creatures by global warming in the Cretaceous, but the earth and creatures got over the crisis in collaboration.

The carbon dioxide has to be got rid of from the atmosphere so as to prevent the greenhouse effect. Seawater and forest absorb the carbon dioxide at present, but as temperature on the…

【The great accident on the earth in the time of dinosaurs】

《Coral reef and sludge saved the crisis on global warming and brought us petroleum》

…but as temperature on the seawater rose the ability on absorbing the carbon dioxide became low, and decreasing the land, it made the forest decrease, so there was almost no effect on decreasing the carbon dioxide.

Then instead, the one who played a part of absorbing the carbon dioxide was coral reef and sludge.

Carbon dioxide in the atmosphere or in the sea became organic matter through photosynthesis, without dissolving, the organic matter was…