Re: OOL I - Manifesto and metatheory
- From: rem642b@xxxxxxxxx (tinyurl.com/uh3t)
- Date: Sat, 2 Apr 2005 20:29:27 -0500 (EST)
> From: "Perplexed in Peoria" <jimmenegay@xxxxxxxxxxxxx>
> Date: Sun, 27 Feb 2005 01:04:41 -0500 (EST)
(Sorry for tardy reply but I had no way to post back then. I've now
finally finished my 5-part reply to OOL X, so now I have time to catch
up with responding to your earlier articles in this series.)
> The problem is to explain how life as we know it came to be.
May I assume you consider that problem to be in two parts:
- How any "life" whatsoever came to be originally;
- How that very first "life" evolved to life as we know it.
and, based on my reading your articles to-date, that you are primarily
discussing the latter part of that second part, i.e. nothing about
original OOL (first successful replicator), and nothing about major
part from there to where you pick up the topic?
> This is a larger and broader problem than most OOL theorists address.
Are you saying most OOL theorists pick one tiny part of the overall
sequence (abiotic -> OOL -> OOLAWKI) and ignore all the rest as if it
wasn't a problem?
> Many of them see the origin as a event - something that happened once.
> They focus on some key feature of life (at least it seems to them to be
> the key feature) and try to explain ITS origin.
Do they first described the whole sequence, and then explain why one
key step is the "most difficult" to solve, as motivation for why they
concentrate on that one step?
I personally consider the step from abiotic chemistry to the first
successful replicator to be the most difficult to solve. Once that's
acomplished, I see the next several steps (to food-webs of various
replicators, then to micro-ecosystems isolated from each other, then to
polymers of replicators) to be relatively easier. Then the wonders of
Darwinian evolution suffice to handwave the rest as explained.
> Others see the origin as a process - something that took place over time.
> They look for some kind of organizing principle for life's origin that
> is perhaps as profound as Darwin's NS. ...
> A typical example of such a theorist might be Stuart Kauffman.
I'm not sure what kind of thinking you're referring to.
Do you know of an online summary of Stuart Kauffman's idea?
> Slogan: Neither an event nor a process. It is a series of events.
Well, I'd say it's a series of events, each event occurring by means of
some process, i.e. a series of process/event pairs. For example, per my
speculation, the process of chemical cascades from high-energy sources
randomly explores a search space of innumerable chemical species, some
with catalytic capability, randomly extending catalytic chains of
various lengths into this search space, until by chance one of these
catalytic chains accidently closes a loop such that the fecundity
around the loop is greater than 1, and if by lack of bad luck the loop
cycles around several times so that more than ten or so copies of each
chemical species (or type) is present, then the loop will surely
continue to grow expontially, thereby achieving the event of origianl
OOL (first successful replicator). After formation of the Earth and
other totally non-biotic events, that's the first process/event pair
along the path to life AWKI.
Note that with supernatural intervention to make all the steps happen
like magic, all you have are events, no corresponding processes, just
magic events happening because goddidit.
So I guess if you are looking for natural processes to explain OOLAWKI,
you need to discuss event/process pairs, but if you don't want to
pre-judge against supernatural intervention, then all you can say for
sure is events. Maybe the right way to look at this is that your
proposed theory will involve event/process pairs, nothing supernatural
at all, and if anybody wants to propose an alternative ID theory with
event/magic pairs that's up to the other person to propose. Without
either an event/process-pairs theory, or an events/ID theory, we can't
really say any sequence of events happened at all, for all we know
everything AWKI appeared already formed last Thursday, and all supposed
prior events are fictional.
> In my mind, the "Origin of Life" comprises at least everything that
> happened leading up to the MRCA (most recent common ancestor).
I would term that whole sequence OOLAWKI rather than just OOL which
would refer to just the first big step from abiotic non-life to first
just-barely-life. To avoid ambiguity, maybe you should specifically
call your topic OOMRCA.
> In fact, I don't think that it goes too far to include the origin of
> eukariotes and sex in the package as well.
(Tiny nitpick: When you express an opinion, a judgement, "In my
opinion" rather than "In fact" would see more appropriate language.)
If there were a clear distinction between life and non-life, as
ancients mistakenly believed, and some religious people still believe,
then OOL would have a clear singular meaning, the transition from
non-life to life. But given the debate over a defintion of life, hence
the debate over what steps properly belong in "OOL", I think it's best
to just admit OOL is too vague, and rather than fret over how broad you
should define OOL, it's best to not use the term "OOL" at all, instead
just say explicitly what you plan to discuss. So have you decided what
you really plan to include, (1) just OORNA as your first ten articles
cover, or (2) OORNA+DNA i.e. OOMRCA, or (3) OOMRCA+eukariotes+sex?
> for the later stages we KNOW there was a process - natural selection.
> At earlier stages, there may have been a different process, or more
> likely, a sequence of different processes.
At each step there were at least two different processes going on, the
actual biochemistry that ran day-to-day business, and the principle of
natural selection that caused evolution that caused the next step to
happen. If you mean that there was some principle other than natural
selection that made evolution happen during the early days, then I
disagree. It was natural selection, in various forms, all the way from
the first replicator to today. Only the biochemistry running day-to-day
business changed from time to time.
For example, per my scenerio, as soon as the first successful
replicator occurred, a trivial form of natural selection occurred,
whereby that one replicator out-competed all other chemistry with the
exception of bulk inorganic chemistry (such as UV irradiation of
methane which continued so long as there was no ozone layer to block
the UV from arriving). Then as soon as several additional successful
replicators came into existance, consuming some of the waste products
from the first successful replicators, then there might have been a
less trivial form of natural selection with some replicators competing
against others for access to food. That's basically included within the
form of theory proposed by Darwin, prior to knowledge of Mendel's study
of (diploid/meiotic) heritance and prior to knowledge of base-triplet
coding. Then later when micro-ecosystems completed as gestalts, that's
closer to the kinds of multi-character-per-genome examples that Darwin
had in mind. The point is that even though such early forms of natural
selection were grossly different from that which happens with modern
base-triplet coding, still the basic theory of NS (Malthus+variation)
would apply just fine IMO.
> What was the first "biochemical reaction"?
If we separate abiotic chemistry from biochemistry per Beilstein vs.
specifically-constructed chemical species, then the first "biochemical
reaction" was any one of the several chemical reactions performed by
the first successful replicator. If that FSR was a simple catalytic
loop, generated in the way I proposed, then the FSR wasn't established
as such until there were already appx. ten or more copies of each of
the catalyists in the loop, so any one of those catalysts could equally
well claim the title as "first", so I think you need to make your
question plural. (On the other hand the ribozyme theory has a *single*
molecule self-replicating, in which case the honor might be singular.)
> What we need is not a "just-so story".
> We need a multi-volume "just-so saga", ...
OK, agreed. A linked chain of "just-so stories", with destination of
each story the starting point of the next, sort of like modular
programming where the public interfaces mesh but the innerds of each
module don't care about each other's innerds. So the "just-so story"
for each step can be judged on its own merit, whether it satisfies a
way we might get from point J to point K, and once each story is
independently judged plausable then a simple graph-theoretical analysis
shows whether the chain as a whole gets from point A to point Z.
> Slogan: Work backward from the present.
This is what fascinates me about your approach. You really do work
backwards, step by step, clue by clue, rather than jumping back a long
way to guess what might have happened early-on as the rest of us have
done.
> Coenzymes are older than enzymes.
For the benefit of we who haven't had formal courses in biochemistry
and have heard of coenzymes and enzymes but don't clearly understand
the difference and how each plays a role in biochemical pathways, do
you know of a good WebPage that summarizes a "typical" biochemical
pathway and a "typical" single step along such a pathway, emphasizing
the different roles that enzymes and coenzymes play there?
> Slogan: Clues regarding OOL may be found in modern biochemistry.
Of course you mean clues regarding OOLAWKI or OOMRCA.
(This response is getting long, splitting here.)
.
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