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As the end of the Permian Period, which occurred 248 million years ago. The Great Dying. About 96 percent of known species on Earth became extinct; and creatures that exist today are descended from the remaining 4 percent.
The last mass extinction Cretaceous-Tertiary (KT) made a name dinosaurs lived 65 million years ago. At that time, a large meteor struck the Earth and is believed to lead to an unimaginable catastrophe.
The massive eruption of the volcano, the movement of the Earth, and comets on the list triggers mass extinction. However, scientists found a common thread 3 of 5 mass extinction ever.
The key word is balance constituent elements of life.
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Too much zinc, copper, cobalt, phosphorus or selenium will poison the environment. Instead, the element that is too little means that important chemical processes - such as the production of antioxidants - impossible.
Natural events: the eruption of volcanoes, tectonic activity, and soil erosion, it acts as the controller.
Earth tireless provide life-supporting nutrient supply. However, not enough mineral ejected onto the surface.
Paleontologists Australia, Professor John Long said, a study by Flinders University and the University of Tasmania shows that these elements flow dries up during long periods of inactivity geology. It makes Earth insufficient supply of nutrients.
Long and his team who come from many countries to learn a number of samples of marine sediments, which provide instructions flashback to the past 3.5 billion years ago - reveals the impact of the life, death, and coastal erosion in the world's oceans.
Scars time line in the sand showed, once the crisis is important mineral Selenium (Se) in the oceans on three of five mass extinction ever occurred on Earth: Period Ordovician, Devonian and Triassic.
All things, from phytoplankton smallest to the biggest dinosaur, so the victim.
Professor Long pointed out, the results of the forensic analysis on the seabed indicate that the drop in supply of Selenium in the late Devonian Period kill Dunkleosteus placoderm - protected predatory fish thick plates - massively, before the oxygen supply is depleted sharp destroy the remaining species.
Dunkleosteus placoderm is a predatory fish. Although protected shield, he had survived the mass extinction Devonian era (Credit: Professor John Long, Flinders University)
At the end of the Triassic Period, a number of marine reptiles such as nothosaur and Ichthyosaur, perished.
Allegedly the suspect obliteration creatures of that era is the collision of asteroids or comets. However, the evidence supports
that notion was not entirely valid.
The research results reveal that Professor Long selenium supply shrunk by abnormal at the time.
"With further analyzes of rock samples were recorded traces of the past 3.5 million years ago, we may have an explanation of the mass extinction events on Earth; also a time when life returned to this planet," said Professor Long was quoted as saying on the News .com.au,
Professor of Geology at the University of Tasmania, Ross Large said the study carried out using the latest laser analysis techniques, which measure the concentration of Selenium on more than 4,000 samples.
"All of it is an invaluable resource to answer many of the unsolved mysteries of the ancient ocean," he said.
The oceans today containing 155 parts per trillion (ppt) Selenium. During the Devonian and Triassic, the sample indicates the element level dropped significantly.
Selenium deficiency is still a problem for humans. Outbreaks in China and Africa - including the mutation of the virus to AIDS, SARS, Ebola and bird flu associated with the human body's immune system is decreased due to lack of essential elements in the Earth's.
Professor Long said, scientists are finding out from the record level of selenium in the soil deposits for further mengeksaminasi why some ancient species extinct, and others survived.
Plate Tectonics and Life
Most of the nutrients contained in the oceans is derived from erosion - from rivers and beaches. Over time, the dissolution of minerals from rocks made available to support life.
Professor Long said, there is an active geologic periods, where the tectonic plates creates a mountain range, bringing fresh mineral deposits close to the surface.
Combined with long periods of bad weather - for millions of years - it could significantly increase the availability of trace elements forming life.
The increase was partly responsible for the explosion of biodiversity in the form or the Cambrian phyla in the Cambrian era, the largest in the history of our planet.
On the other hand, erosion is reduced or lack of geological activity can reduce the level of nutrients of life.
"While the link between the nutrient cycle as the driving factor in the evolution and extinction event is still to be proved, these findings open our eyes to evolution in a broad sense," writes Professor Long.
"Plate tectonics and evolution, both operating at a period of millions of years. Logis if we think that they are related."
Studies show that in the last century, when more than 400 vertebrate disappeared, extinction level at least 114 times higher than normal levels.
Three leading universities in the US was warned, people can be the first affected.
Another cause of the mass extinction that is happening on Earth. One of the triggers are air pollution, mass extinction driver was not separated from human activity: climate change, pollution, and overfishing.
The research results reveal that Professor Long selenium supply shrunk by abnormal at the time.
"With further analyzes of rock samples were recorded traces of the past 3.5 million years ago, we may have an explanation of the mass extinction events on Earth; also a time when life returned to this planet," said Professor Long was quoted as saying on the News .com.au,
Professor of Geology at the University of Tasmania, Ross Large said the study carried out using the latest laser analysis techniques, which measure the concentration of Selenium on more than 4,000 samples.
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The oceans today containing 155 parts per trillion (ppt) Selenium. During the Devonian and Triassic, the sample indicates the element level dropped significantly.
Selenium deficiency is still a problem for humans. Outbreaks in China and Africa - including the mutation of the virus to AIDS, SARS, Ebola and bird flu associated with the human body's immune system is decreased due to lack of essential elements in the Earth's.
Professor Long said, scientists are finding out from the record level of selenium in the soil deposits for further mengeksaminasi why some ancient species extinct, and others survived.
Plate Tectonics and Life
Most of the nutrients contained in the oceans is derived from erosion - from rivers and beaches. Over time, the dissolution of minerals from rocks made available to support life.
Professor Long said, there is an active geologic periods, where the tectonic plates creates a mountain range, bringing fresh mineral deposits close to the surface.
Combined with long periods of bad weather - for millions of years - it could significantly increase the availability of trace elements forming life.
The increase was partly responsible for the explosion of biodiversity in the form or the Cambrian phyla in the Cambrian era, the largest in the history of our planet.
On the other hand, erosion is reduced or lack of geological activity can reduce the level of nutrients of life.
"While the link between the nutrient cycle as the driving factor in the evolution and extinction event is still to be proved, these findings open our eyes to evolution in a broad sense," writes Professor Long.
"Plate tectonics and evolution, both operating at a period of millions of years. Logis if we think that they are related."
Studies show that in the last century, when more than 400 vertebrate disappeared, extinction level at least 114 times higher than normal levels.
Three leading universities in the US was warned, people can be the first affected.
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