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Earth "won" oxygen 2.33 billion years before

Earth "won" oxygen 2.33 billion years before

the first significant, irreversible flow of oxygen in Earth's atmosphere occurred nearly 2.33 billion years, which is, after all, led to the emergence of multicellular life, but scientists have recently succeeded in a margin of error in the such numbers are reduced to "only" plus-minus seven million years.

In this way, according to research experts of the American Institute of Technology Massachusetts (MIT), published in the scientific journal "Science Advances", reduced the current margin of error that ranged between ten million and hundreds of millions of years. The discovery came analyzing sediment cores and determining the main crossing in the form of an independent mass fractions of isotopes of sulfur (S-MIF). Iatoday when 21 percent of the Earth's atmosphere makes oxygen, the gas was not always enough to make it benefit sentient beings, moreover, during the first two billion Earth's history it is not enough. the researchers found that the increase of oxygen in the atmosphere, although very small, lasting from one million to ten million years, and then caused a chain of events that ultimately resulted in the emergence of multicellular life.

"that was the beginning of a long period culminated in the creation of complex life. It took roughly about 1.7 billion years to evolve animals similar to those that we know today, "said the professor of the Department for terrestrial, atmospheric and planetary exploration (EAPC) MIT Roger Samons.

Scientists generally agree that the oxygen emerging in the oceans as a byproduct of photosynthesis cyanobacterial a three billion years and that the atmosphere was not because he was in fact prevented hungry microbes or iron. "Perhaps before any interim releases oxygen into the atmosphere, but their abundance and duration of the current can not to measure, "said Samons, who explained that it all changed a great oxidation. As pointed out by precisely defining the beginning of the so-called high oxidation could experts to uncover the causes and mechanisms of this important event for the living world on Earth. Samonsov team would like to investigate the hypothesis that there is no connection between the "sudden and rapid" with the appearance of oxygen in the Neoproterozoic ice age (geological period that began a billion years ago and ended before 541 million years ago) that was so sharp that the Earth's oceans completely froze (theory of the Earth as a snow-balling).

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