[...]
>>>DNAunion: Neither the maintenance of preexisting life nor the evolution
of preexisting life are the real issues: these can be explained by relying on
the highly-complex preexisting biochemistry of cells (but *still* require the
continual struggle against the natural tendency of entropy to increase, and
for reactions to reach equilibrium). The origin of life is different, as
there were then no preexisting closed metabolic cycles, no specified complex
information as found in genomes, and no complex enzymes. How did pools of
simple, random, organic molecules, operated upon by undirected and
uncontrollable energy sources only, become so ordered, complex, and
*organized* to produce the first cells?
>>> Chris: Autocatalyzing sets of molecules might easily be able to do
evolve into
cells.
DNAunion: Easily? Where are the experiments that confirm that this could
occur "easily"? Or even at all?
>>>Chris: Further, the first cells may well not have been the first *life.*
DNAunion: Which is only possible because of ambiguity added to the
definition of life fairly recently. The long-held cell theory made it quite
clear: anything composed of one or more functioning cells was living;
anything that wasn't composed of one or more functioning cells was not
living. The addition of yet another "definition" of life - the minimalist
definition supported by OOL researchers (allowing a self-sustaining,
self-replicating *molecule* to qualify as living) - is what makes this point
of contention you mention possible.
All life we know of, and have fossil evidence of, consists/consisted of one
or more functioning cells. But a cell (with ribosomes, DNA, RNA, proteins,
enzymes, plasma membrane, anabolic and catabloic pathways, replication,
transcription, translation, etc.) is too complex/complicated of a target for
those looking at purely-natural causes, so they set their sights (and tried
to set ours) much lower by looking to single molecules.
Irregardless of whether or not the first living entity was a cell, the full
complexity, complication, and organization of a autonomous cell must still be
explained by purely-natural causes if abiogenesis is valid. *They can try to
redefine the starting point of life, but that does not rid them of the
ultimate burden of explaining, using only purely-natural processes, how the
first cells came to be*.
>>>Chris: Evolution can occur without life, and life might occur without
cells.
DNAunion: Well, "evolution" (progressive change occurring through rounds of
mutation and selection of the most fit variants) has been shown to be
possible in silico (evolutionary algorithms manipulating field-programmable
gate arrays). But that required life (well, at least intelligence) to
achieve. The experiment showed that "evolution" can occur in non-biological
entities, but does not actually demonstrate that "evolution" can occur
without life/intelligence. Unless you had something else in mind.
The other point, that life might occur without cells, is still theoretical.
Or does anyone here know of any life that is not based on cells? (Viruses do
not count, as scientists cannot agree on whether or not they are living)
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