When I was formulating this theory, I thought I would need to convince the reader that meteorites delivered most of the amino acids needed to initiate Emergent Chemical Evolution (ECE). But thanks to Z. Martins and others I do not have to try so hard anymore; because back in 2007 they wrote an article on this very subject. In which they claim that the amino acids delivered by chondrites would have played a part in starting life on earth . This is one of the central claims of Emergent Chemical Evolution.
The necessity of some scientists to prove how amino acids were produced on Earth from scratch seems to be totally unwarranted. Especially when, for over thirty years, it has been commonly known that chondrites contain, since before the formation of the solar system, over seventy different types of amino acids. And there is overwhelming evidence that there was a period of heavy bombardment just prior to the emergence of life.
I propose that these meteorites were the primary source of the amino acids that were necessary for the emergence of life and that it was also unnecessary for the Earth to produce any amino acids for that purpose.
Well that was going to be my argument anyway. But now I feel that the authors of the previous article have very eloquently proven my point. But it does not end there. Another article published on August 10, 2012 in Science magazine goes even further than that. Alexander et al proved that chondrites not only contributed amino acids to earth but also delivered all volatile material: water, hydrogen, carbon, and nitrogen.
One of the problems faced by geologist was explaining how the Earth got its water and other volatile material after it had melted soon after its formation. Once the Earth had amassed itself from the debris of the solar nebula at some point it reached a critical mass. When that critical mass was reached something spectacular occurred, between its own gravitational pull and the amount of nuclear material contained within it, the entire Earth melted. That means that every inch of the entire planet would have been above 1300°F.
At that temperature all volatile material like water, carbon, hydrogen, all gases would have been burnt and irradiated out into space. Alexander et all, I believe, have provided compelling evidence of not only the source of the oceans but also of its contents as well.
To clarify the significance of these two articles for the Theory of Emergent Chemical Evolution I need to add the fallowing statements: First, these two articles make it abundantly clear that the prebiotic oceans were full of amino acids. Second, that without the massive bombardment there would have been no starting material for the Earth to cook up amino acids in the first place.
Therefore, there is no need to investigate or to recreate chemical mechanisms that would help explain how amino acids formed on Earth. The amino acids that were needed, for Emergent Chemical Evolution to occur, were not synthesized on Earth but were simply brought here by meteorites during the heavy bombardment!
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