At 09:16 PM 11/11/2000, you wrote:
> >>>Ccogan: Since reproduction can occur either as a mere catalytic
> process, a
>template-using process, or as a process of creation and assembly of
>components (as in virus replication), there are plenty of ways in which the
>Sun's energy, and the energy from the core of the Earth itself, etc., can
>promote reproduction once this energy has brought about enough natural
>"mixing" of existing components to produce the first simple and suitable
>replicator.
>
>***************
>DNAunion: First, you listed three "independent" methods of reproduction, as
>if any one of the three can stand by itself. But these are not independent.
>"[A]ssembly of components (as in virus replication)" does not occur without
>there first being "a template-processing process", which does not occur
>without a "catalytic process". Note also that you later state, "even the
>simplest catalytic process is "code-driven,"", which seems to further
>entangle these "independent" processes of reproduction.
Chris
Well, I can see your point. Nevertheless, not all catalysis is
template-based, and not all creation and assembly of parts is
template-based, either, and it need not even be catalytic in any ordinary
sense, though I suppose, technically, *any* process whereby something
causes or triggers something to happen may be considered to be catalytic,
at the expense of diluting the value of the term.
A machine can create another machine by assembling existing small parts
into larger assemblies and then assembling the assemblies into the new
machine (which may be a copy of itself), *or* it can provide information to
*another* machine that then creates the sub-assemblies and then let's the
sub-assemblies assemble themselves (assuming they are the types of
sub-assemblies for which this is possible). We would normally equate the
second method with catalysis, but would not do so with the first method. I
see no reason why molecules may not do something similar in both cases.
DNAunion
>Second, you have glazed over some of the most important steps on the way to
>life: how the first self-replicators arose.
Chris
Actually, I've dealt with this in previous posts, though by no means
exhaustively. Self-replicating molecules are not exactly uncommon. Even
slightly *evolving* self-replicating molecules have been observed (in
laboratory research, admittedly). A simple A-B template molecule such that
A attracts and holds another B, and the B attracts and holds another A,
until there is *both* another A and B, which then join and break free from
the original molecule will work. I don't actually know, of course, how the
original replicator molecules might have occurred, or even what they might
have been. However, I'd bet that a good chemistry-simulating program could
find a fair number of them quite rapidly (to be followed by real-world
testing, of course). (I understand that one such program has recently been
written in the programming language Prolog, which is a remarkable tool in
itself, aside from the power of some of the programs written in it).
DNAunion
>You have basically done what
>Paul Robson claims no evolutionist does! You have presented a *vague appeal*
>to open-system thermodynamics ("there are plenty of ways in which the Sun's
>energy, and the energy from the core of the Earth itself, etc., can promote
>reproduction once this energy has brought about enough natural "mixing" of
>existing components to produce the first simple and suitable replicator.")
Chris
No, I haven't. It's not vague at all. It is merely incomplete, and I bring
it up not to *prove* abiogenesis, but only to support the claim that
abiogenesis is not implausible, and that it deserves serious consideration,
not the casual, mindless dismissal that so many give it.
DNAunion
>At least you didn't rely solely on the sol (pun intended) and brought up the
>energy made available from the Earth's core. But still, your explanation for
>the generation of the first replicators boils down to, "energy did some
>mixing of stuff in some unspecified way".
Chris
Yes and no. It's not intended to be a complete explanation. No more than
any other evolutionist do I believe that the mere passing-through of energy
is *sufficient* for the generation of replicators. I've also (partially)
covered other conditions necessary for the generation of replicators in
previous posts. One is that there be an information-storage medium (such as
molecules) that is such that it is stable enough to continue to exist long
enough to be replicated. Another is that it not be *so* stable that it
cannot be modified by available forces. If it is too stable, nothing
happens. If it is too *unstable*, it can't store information long enough
for useful replication to occur. Carbon, oxygen, sulphur, hydrogen, and so
on, in conditions that appear to have existed about 4 bya seem to be such
that they could form such molecules. Water in certain temperature and
pressure ranges will allow the semi-stable existence of a large variety of
molecules (different sets of such molecules at different pressures and
temperatures, of course). Dirt provides a good source of many minerals that
can be used in making various molecules.
There are literally billions of possibilities to be considered, and hardly
any of them *have* been considered, so it is not surprising that I can't
supply much greater specificity. Also, this is not my primary field of
study, though I am interested in it. I was basically expanding on Richard's
remarks.
> >>>Chris Cogan: Once that replicator exists in a suitable environment, it
>will proceed to "saturate" that environment, unless it first produces fitter
>variations.
>
>***************
>DNAunion: Wasn't it you who said elsewhere that you were equating life with
>replication?
Chris
No. I equate it with the active use of energy by the living thing itself,
rather than passively waiting for the environment to do things for it. Life
and replication are not necessarily joined. Life might come *quite* some
time after replication and evolution have been in progress. It might even
occur in molecules that cannot replicate at all. We, of course, would not
see much of this kind of life around because it would all die out
eventually without leaving any progeny. It would, I'd expect, be all
smallish molecules that would constitute a nearly immeasurably small
proportion of life in general not long after the first good replicating
life form came along.
>If so, then you have already explained the origin of life:
>"energy did some mixing of stuff in some unspecified way".
>***************
>
> >>>Chris Cogan: Saturation yields serious selection: From this point on,
> the
>molecules that dominate will be the ones that are best at getting reproduced
>in the crowded environment with limited resources out of which new copies of
>themselves can be made. At this point, opportunities for predation become
>important, as do variations that can take advantage of otherwise unused
>factors in the environment, such as other substances and other sources of
>energy.
>
>****************
>DNAunion: Agreed.
>****************
>
> >>>Chris Cogan: Further, since even the simplest catalytic process is
>"code-driven," there is also no lack of code-driven processes, though this
>is, as someone pointed out, in *addition* to having an energy source.
>
>****************
>DNAunion: I disagree. First, magnesium ions (and other inorganic ions)
>catalyze a lot of reactions. Unless you are being extremely, extremely
>flexible with the term "code-driven" - which you would need to justify if so
>- then there is no such "code-driving" involved in the "simplest of catalytic
>processes".
>
>Second, the way the simplest things operate does not necessarily explain how
>the most complex do (loosely, explaining that elevated water will fall does
>not explain how a hydroelectric plant operates).
>*****************
>
> >>>Chris Cogan: All chemical reactions are ways of allowing energy to travel
>"toward" equilibrium. The energy bound up in a molecule produced by the
>application of energy from outside the vicinity is closer to the equilibrium
>level than it was before it contributed to the production of the molecule. It
>will go still closer to equilibrium when it is released later. Replicators
>are a fairly good way to allow energy to pass "through" the biosphere (in and
>then out) on the from the Sun and the Earth's core to open space. This is
>because they use up energy in reproducing, and, if they evolve the ability to
>actively *use* energy, if (in other words) they *live*, they use it up in the
>process of living. Thus, living things are one of the ways the Earth has
>developed to dissipate energy from itself and from the Sun (and from the
>Moon's tidal effects).
>
>********************
>DNAunion: It almost sounds like you are saying the Earth *needs* life in
>order to do something with its energy.
Chris
Not strictly speaking. But, given a bunch of energy to get rid of, it will
effectively "search" out locally available ways to do so. Life is (in some,
but definitely not all, cases) one of those ways.
>********************
>
> >>>Chris Cogan: Since life itself is a pathway for energy flowing toward
>equilibrium, life *depends* on the Second Law (or, more nearly exactly, on
>the facts that we describe by means of the Second Law).
>
>**************
>DNAunion: I get the impression you emphasized the word *depends* as some sort
>of a counter to my position: it is not. Of course life *depends* on the 2nd
>law, and of course life doesn't violate the 2nd law. I have not said
>otherwise.
>
>Let me use yet another analogy. Even though a hydroelectric power plant
>*depends* on gravity, and at no point during its operation does it violate
>gravity, gravity alone cannot explain how the electricity comes out of the
>plant. There are "coupling mechanisms" that couple the flow of water with
>the flow of electric current (basically, falling water rotates a "water
>wheel", which has gears, and those gears mesh with gears on a shaft, so the
>rotation is transmitted to the shaft, which has wires attached such that they
>are set in motion relative to stationary magnets - that is, they rotate
>between the poles of the magnet - which induces an electric current in the
>output wires). Can one rely on gravity alone to explain how a hydroelectric
>plant produces electricity? No; the coupling mechanisms are required also
>and must be included in any sort of a full explanation. Can one rely on
>thermodynamics alone to explain how a cell functions? No; the coupling
>mechanisms are required and must be included in any sort of a full
>explanation. We can explain how the coupling mechanisms in the hydroelectric
>power plant first arose, but how did those in cells first arise?
Chris
Magic? :-)
Actually, we need quite a bit more than energy and "coupling mechanisms,"
but we certainly do need to say how the energy did its thing, I agree.
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