By:
Howdy Doody Conservative
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A terrific documentary about how the Earth and life got started.
This is not a climate change video.
I hope you enjoy it.
In the very beginning of earth's history, this planet was a giant, red hot, roiling, boiling sea of molten rock - a magma ocean. The heat had been generated by the repeated high speed collisions of much smaller bodies of space rocks that continually clumped together as they collided to form this planet. As the collisions tapered off the earth began to cool, forming a thin crust on its surface. As the cooling continued, water vapor began to escape and condense in the earth's early atmosphere. Clouds formed and storms raged, raining more and more water down on the primitive earth, cooling the surface further until it was flooded with water, forming the seas.Scientists are still trying to unravel one of the greatest mysteries of earth: When did "life" first appear and how did it happen? It is estimated that the first life forms on earth were primitive, one-celled creatures that appeared about 3 billion years ago. That's pretty much all there was for about the next two billion years. Then suddenly those single celled organisms began to evolve into multicellular organisms. Then an unprecedented profusion of life in incredibly complex forms began to fill the oceans. Some crawled from the seas and took residence on land, perhaps to escape predators in the ocean. A cascading chain of new and increasingly differentiated forms of life appeared all over the planet, only to be virtually annihilated by an unexplained mass extinction. It would be the first of several mass extinctions in Earth's history.
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