The problem is naturally dual in nature and yet all the inherent
components are available in part or in whole. Just how does a bucket
of nuts and bolts self assemble into an aware state?
Can we even imagine a least action? Playing around with zeolites, we
can work up self catalytic environments to generate a lot of complex
molecules. So how does it resolve into a chemical version of the
mathematical game of Life?
Because we can in fact emulate the situation in two dimensions it is
a simple imaginative extension to project the production of
increasingly complex molecules. Yet we are going to have to get it
right and then observe it in action. Going from there to self
replicating DNA has to take time and encasing it all inside a organic
bubble a great deal more complexity. Yet it may turn out to be easy.
I am sure that the tools exist and what is left is the time and best
conditions and really good imaging tools to sort out wheat from
chaff.
ASU researchers
propose new way to look at the dawn of life
by Staff Writers
Tempe AZ (SPX) Dec 18, 2012
One of the great
mysteries of life is how it began. What physical process transformed
a nonliving mix of chemicals into something as complex as a living
cell?
For more than a
century, scientists have struggled to reconstruct the key first steps
on the road to life. Until recently, their focus has been trained on
how the simple building blocks of life might have been synthesized on
the early Earth, or perhaps in space. But because it happened so long
ago, all chemical traces have long been obliterated, leaving plenty
of scope for speculation and disagreement.
Now, a novel approach
to the question of life's origin, proposed by two Arizona State
University scientists, attempts to dramatically redefine the problem.
The researchers - Paul
Davies, an ASU Regents' Professor and director of the Beyond Center
for Fundamental Concepts in Science, and Sara Walker, a NASA
post-doctoral fellow at the Beyond Center - published their theory in
the current issue (Dec. 12) of the Royal Society journal Interface.
Their article is titled "The algorithmic origins of life."
In a nutshell, the
authors shift attention from the "hardware" - the chemical
basis of life - to the "software" - its information
content. To use a computer analogy, chemistry explains the
material substance of the machine, but it won't function without a
program and data.
Davies and Walker
suggest that the crucial distinction between non-life and life is the
way that living organisms manage the information flowing through the
system.
"When we describe
biological processes we typically use informational narratives -
cells send out signals, developmental programs are run, coded
instructions are read, genomic data are transmitted between
generations and so forth," Walker said. "So identifying
life's origin in the way information is processed and managed can
open up new avenues for research."
"We propose that
the transition from non-life to life is unique and definable,"
added Davies. "We suggest that life may be characterized by its
distinctive and active use of information, thus providing a roadmap
to identify rigorous criteria for the emergence of life.
"This is in sharp
contrast to a century of thought in which the transition to life has
been cast as a problem of chemistry, with the goal of identifying a
plausible reaction pathway from chemical mixtures to a living
entity."
Focusing on
informational development helps move away from some of the inherent
disadvantages of trying to pin down the beginnings of chemical life.
"Chemical based
approaches," Walker said, "have stalled at a very early
stage of chemical complexity - very far from anything we would
consider 'alive.' More seriously they suffer from conceptual
shortcomings in that they fail to distinguish between chemistry and
biology."
"To a physicist
or chemist life seems like 'magic matter,'" Davies explained.
"It behaves in extraordinary ways that are unmatched in any
other complex physical or chemical system. Such lifelike properties
include autonomy, adaptability and goal-oriented behavior - the
ability to harness chemical reactions to enact a pre-programmed
agenda, rather than being a slave to those reactions."
"We believe
the transition in the informational architecture of chemical networks
is akin to a phase transition in physics, and we place special
emphasis on the top-down information flow in which the system as a
whole gains causal purchase over its components," Davies
added.
"This approach
will reveal how the logical organization of biological replicators
differs crucially from trivial replication associated with crystals
(non-life). By addressing the causal role of information directly,
many of the baffling qualities of life are explained."
The authors expect
that, by re-shaping the conceptual landscape in this fundamental way,
not just the origin of life, but other major transitions will be
explained, for example, the leap from single cells to
multi-cellularity.
In addition to being a
post-doctoral Fellow at the Beyond Center, Walker is affiliated with
the NASA Astrobiology Institute in Mountain View, Calif., and the
Blue Marble Space Institute, Seattle.
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