<< 
JM
Ok, but RNA does NOT survive in the environment you are talking 
about: 

Matthew Levy and Stanley L. Miller
The stability of the RNA bases: Implications for the origin of life
PNAS 1998; 95: 7933-7938.
http://www.pnas.org/cgi/reprint/95/14/7933

Excerpt:
We show here that the rapid rates of hydrolysis of the nucleobases 
A, U, G, C, and T at temperatures much above 0°C would present a major 
problem in the accumulation of these presumed essential compounds on 
the early Earth. A high-temperature origin of life involving these 
compounds therefore is unlikely.

TH
This is a very real problem with my scenerio.
Also with the evidence pointing to early life
developing in such a hot environment.

NEW TH
I got to read this and think about it some more.
This is a very real problem with ALL scenarios
if it is right - but I'm not so sure it would prevent
life from happening.

Note that it seems Mars had water. That means that
if mars was up to 0-100C, then closer-to-the-sun
Earth must have been HOT. Miller/Levy says no way.
Also they point to the problem of hydrolysis - but
what if there was a dry phase. Also they mention how
long these bases would last (if there is not a single way that they are getting
an once of help from any other
source) - which equals a wide range that is not
completely prohibitive though it is pretty short.

In the end I think there is lack of knowledge here to
fit all the facts together. I can't escape the fact
that it seems the earth was HOT. How then do these
bases survive? Solving that may tie them in with
amino acids and give the reason why RNA needed
protein in the first place.
I see your point but am not completely convinced.

Also remember that each selected step in life
gives greater thermal stability - folding of a strand
over non folding, paired strands over single, WC base
pairing over other less stable types, base stacking over
not base stacking - etc.

And I add this - why does RNA have such a high Tm
(higher than even DNA) if it never was selected for
needing it?

Comment?
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