Shapiro Article - responses.
- From: TomHendricks474@xxxxxx
- Date: Fri, 16 Feb 2007 17:21:18 -0500 (EST)
Here's some responses to the Robert Shapiro article in Sci.Am.
Shapiro:
In a form of
molecular vitalism, some scientists have presumed that nature has an
innate tendency to produce life's building blocks preferentially, rather
than the hordes of other molecules that can also be derived from the
rules of organic chemistry.
Hendricks
NO - life process have the tendency to adapt to nature or be destroyed.
None of these hordes of other molecules are still around. They were not
stable. All life processes are still around - they were most stable in
that environment. Maybe its time to talk - not about selfish genes -
but selfish nucleotides, proteins, and ATP!
Shapiro
There is no reason to presume than an indifferent nature would not
combine units at random, producing an immense variety of hybrid short,
terminated chains, rather than the much longer one of uniform backbone
geometry needed to support replicator and catalytic functions.
Hendricks
Yes of course, but every natural response that continues to exist in
that 'indifferent nature' will be one more likely to be stable than one
that is more likely to be destroyed. Thus every 'life' step is one that
better fits 'indifferent nature'. Life is not some origin pop! outside the
environment. It is the long string of chemical adaptations to the environment.
Shapiro:
The chances for the spontaneous
assembly of a replicator in the pool I described above can be compared
to those of the gorilla composing, in English, a coherent recipe for the
preparation of chili con carne. With similar considerations in mind
Gerald F. Joyce of the Scripps Research Institute and Leslie Orgel of
the Salk Institute concluded that the spontaneous appearance of RNA
chains on the lifeless Earth "would have been a near miracle." I would
extend this conclusion to all of the proposed RNA substitutes that I
mentioned above.
Nobel Laureate Christian de Duve has called for "a rejection of
improbabilities so incommensurably high that they can only be called
miracles, phenomena that fall outside the scope of scientific inquiry."
Hendricks:
Yes of course. And I'm glad you see the obvious. Thus a pop and adapt
origin event is out. Yet if we see life as those chemical responses
that continued to exist because they are more stable. Then it isn't
a fluke event, it is an inevitability in that environment,
an environment that apparently we had on earth. (This is the
real question of how life processes were a response to the environment.
What was the environment? How hot? What was the temperature
range, how much uv, the atmosphere, etc.)
Shapiro doesn't see life as I do, as the most stable reaction to the
environment (thus every step toward complexity would
NOT be a struggle but a selection process that with each
step makes it a BETTER, more stable fit - thus 'life processes' are
ALWAYS SELECTED FOR. That resolves most of the stated problems.
The research community seems to be looking for a pop and adapt scenario
where either metabolism and/or replication pops up
through some creation moment-event-origin, and then life leisurely
adapts in an environment it just popped up in!?
Shapiro lists his 5 requirements the origin event.
I follow each with my comments.
1) A boundary is needed to separate life from non-life.
Why - for more stability of course! The non-boundary ways
were less stable and didn't last in that environment.
2) An energy source is needed to drive the organization process.
Backwards - the energy source, the sun/uv heat cycle, drove
the chemicals to respond to the environment in ways that either
made them more stable or destroyed them. Chemicals never want
energy. They , over time, can set up systems that use forced energy
as novel ways to continue to exist in a forced energy environment.
(3) A coupling mechanism must link the release of energy to the
organization process that produces and sustains life.
Like chemicals need energy, or want to live, or want to get to us?
Take the anthropomorphic 'I" out of evolution and see that every
step is either more stable or destroyed, and stability is selected for.
(4) A chemical network must be formed, to permit adaptation and
evolution.
Why - to fit your definition of life? No the only reason any of
this would happen is if forced energy demanded a response to that
energy that would lead to more stability in that environment.
(5) The network must grow and reproduce.
Why? To fit Darwins descent with modification. But descent to do what
if not to better fit the environment. There is no evolved step that
leads to less stability. Descent with modification is the supreme
example of force energy on chemicals that react in the most stable
way.
Comment?
Tom Hendricks
http://en.wikipedia.org/wiki/Tom_Hendricks
.
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