Re: Some Cyclical Process Before the First Replicator

On Oct 8, 11:07=A0am, "Perplexed in Peoria" <jimmene...@xxxxxxxxxxxxx>
wrote:
"Tom Hendricks" <tom-hendri...@xxxxxxx> wrote in messagenews:gce66f$241u$=
1@xxxxxxxxxxxxxxxxxxxxxx
Most origin scenarios have a replicator pop up - a single fluke event. =
Then
if they are honest they'll admit the odds of this happening are so
astronomical that it didn't happen or really couldn't happen.

I suggest that a more plausible scenario is this:
Before the first replicator there was some type of chemical process tha=
t
produced RNA variations - probably a sun forced cyclical process. And t=
his
was such a productive process that it produced all types of variations =
of
RNA: folded or double stranded, plus different mixes of purines and
pyrimidines, etc.

This process produced one variant that was a first replicator, or even =
more
likely, many versions of replicators. And that this first group of
replicators led to a 'best of' as we know it now.

But what process would do that? I suggest a process where the sun cycle
forces a denaturing and annealing cycle. The hot sunlight first denatur=
es
RNA and disconnects some strands. Then in night the coolness anneals th=
ese
separate RNA into new variants. Day after day the process repeats until
certain replicators are made.

But overall the point is that some environmental forced process, produc=
ed
many variations in RNA that came before the first replicators. There wa=
s not
one fluke event, no 'pop and adapt' magical chemical wand tap.

Tom, what you have just described is the *standard* RNA first scenario. =
=A0I
don't think there is any such thing in ANYBODY's mind as the "pop-and-ada=
pt"
scenario that you describe. =A0Everyone who believes in RNA-first believe=
s that
the first (fluke) replicator was just one of a huge population of other R=
NA
molecules - all fairly big, all fairly complicated, but only one of which=
could
reproduce itself.

Which, to my mind, is a good reason for rejecting the entire RNA-first sc=
heme.
Surely that first polymerase ribozyme would have "re-produced" the other
non-catalytic RNA molecules in the population far more often than it woul=
d
have "re-produced" itself.

At least in the Cairns-Smith "clay-first" story, being a replicator is no=
big
deal - everyone in the 'population' replicates, though some of them do it
better than others.

First its good to hear from you. I always value your comments.

My point is that its not limited to one that replicates. That's the
part that "pops". Most scenarios
are looking for that one 'pop', then they suggest that magic
replicator 'adapts' to the environment and the rest is life's history.

We should look, not for a replicator, but a PROCESS, that forces ALL
RNA to replicated in a forced denature and annealing
cycle caused by the sun. Then its not one but a group of replicators
of which some are more stable
(stable is my definition for 1. keeping what works, 2. changing what
doesn't work. 3. being able to do both - i.e. life).

So I'm saying Don't look for a single replicatior. Do look for a
process that makes all RNA replicate
on a daily basis ( or some other cyclical period).

Now off on a tangent.
Look at the two sets of bases. It's clear as day that purines are for
stability, and pyrimidines for change.
That fits my stability definition perfectly. Let's ask this, coding
for what? Replicate for what?
I say for something even more stable, something that excluding zircon,
is just about the only thing
that can last for 4 billion years.

RNA was a step in making the chemical reaction to the sun cycle even
more stable (stability with variation).
Life is not a magic replicator that pops and adapts, it is a continual
response of chemicals to the sun cycle
with the most stable in a chemical symbiosis we call life.

That is far from the standard RNA first scenario IMO

.

Relevant Pages

  • Re: Metabolism Forced
    ... Once a simple chemical replicator takes hold of the ... chemicals spontaneously form amino acids, ... > and dominated the oceans and led to life as we know it. ... involves a significantly more complicated cycle of catalysts. ...
    (sci.bio.evolution)
  • Re: Origin - the wrong word?
    ... which when combined with the rest of the chemicals already ... All life is a reaction to a sun/heat cycle. ... Had the environment been a single temp - no life. ... but already at that point billions of copies of the replicator ...
    (sci.bio.evolution)
  • Re: Origin - the wrong word?
    ... which when combined with the rest of the chemicals already ... but already at that point billions of copies of the replicator ... much water as you want. ... They key is that the "replicator" catalyzes its own production in some ...
    (sci.bio.evolution)
  • Re: Origin - the wrong word?
    ... Any RNA sequence as first successful replicator seems ... availability of particular "food" chemicals. ...
    (sci.bio.evolution)
  • Re: OOL X - The origin of the RNA world.
    ... the very first successful replicator was necessarily 100% ... chemicals, then the theory is called "heterotrophic". ... Yours is a "metabolism first" theory, ... a life cycle of several stages, but eventually it reaches the reproductive ...
    (sci.bio.evolution)
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