"TomHendricks474"  wrote in message
news:c8098o$2328$1{at}darwin.ediacara.org...
> <<
> 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.

Not a problem for all scenarios.  Only for those which are either:

* Heterotrophic - they assume that first life did not manufacture
all of its own organic components - that it needed to import them
(as a kind of food) from the environment.

or

* Global - they assume that the local concentration of chemicals
needed to ignite life derive from an only-slightly-lower global
concentration of those chemicals (or their precursors).

That is unfortunate for your theory, as I understand it, because
your theory is both heterotrophic and global.

But don't be too discouraged.  Miller's data can be trusted, but
his interpretation of the data can be taken with a grain of salt.  You
have to understand that Stanley Miller is emotionally attached to
the notion of life's origin that made him famous.  He is psychologically
incapable of recognizing or interpreting theories that might make the
Miller-Urey experiment irrelevant.

If you look at the fine print, the free bases have half lives of hundreds of
years at 60 degC and survive much longer in the kinds of tRNA-like
configurations that you favor.

By the same token, take Shapiro with a grain of salt too.  He is
obviously frustrated that Miller has all that undeserved fame, while
he, just as good a chemist, does not.

Take everything with a grain of salt (and learn enough chemistry so
that you can do so with confidence.)
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