@peter jeffrey cobb,
Good. So now you've seen the RNA World hypothesis and how the atmosphere came to be what it is, thanks to the work of early microbes.
I would remind you here again of the difference between a hypothesis (possible, but unproven) and a theory (proven). Though details of the RNA World hypotheis are still being investigated, it's a pretty robust hypothesis so far:
Quote:One of the problems with the RNA world hypothesis is to discover the pathway by which RNA became upgraded to the DNA system. Kim Stedman of Portland State University in Oregon, may have found the solution. While filtering virus-sized particles from a hot acidic lake in Lassen Volcanic National Park, California, he discvered 400,000 pieces of viral DNA. Some of these, however, contained a protein coat of reverse transcriptase enzyme normally associated with RNA based retroviruses. This lack of respect for biochemical boundaries virologists like Luis Villareal of the University of California Irvine believe would have been a characteristic of a pre RNA virus world up to 4 billion years ago.[58] This finding bolsters the argument for the transfer of information from the RNA world to the emerging DNA world before the emergence of the Last Universal Common Ancestor. From the research, the diversity of this virus world is still with us.
(From the Wiki link above.)
If you want more details, we'd have to start looking into the detailed chemistry. Unless you've had a few chemistry classes, though, I'm not sure how helpful that would be. I've had both chemistry and microbiology classes in college, and I couldn't pull it all up from memory, but I recognize it when I see it.
