> Here's how I see it. At some point, life emerges. Yet life is
information
> and where did this information come from? The information-generating
> examples I have seen invoke genetic variation coupled to selection
> (back to Darwin). But all of this presupposes life which itself
> presupposes information. Paul Davies nicely outlines this problem
> and finds that, as a physicist, when he enters the world of molecular
> biology, he finds himself in unfamiliar territory. How did a dumb
> planet make a cell? Planets make mountains, clouds, oceans,
> atmospheres, but a cell?
Kevin writes:
[snip]
>In any event, the answer is self-organization: molecular structures,
>using the physiochemical laws, are able to form larger, more complex,
>even organized structures on their own.
I must say that you have a far greater sense of certainty about
these things than I do. Self-organization may be the answer (and
I suppose must be the answer if we exclude some form of
intervention by an intelligent agent), but I can't say that it *is*
the answer (although I think it does have a great deal of theological
appeal).
>For example, heating amino acids in the absence of water creates
>polypeptiditic macromolecules with non-random sequences that
>are catalytically active; these are called thermal proteins (many
>people still use the old term proteinoid). These thermal proteins
>are then able to form cellular structures upon rehydration that can
>convert sunlight into ATP, create polynucleotides using thermal
>proteins as templates, and create polypeptides from polynucleotides.
>They can also perform other metabolic reactions, they can grow
>and they can reproduce.
Very interesting. Since these cells grow and reproduce, I would
assume someone has a culture that has been frozen (a common
procedure for microbiologists). Who can I write to in order to
get my hands on these "cellular structures?" Furthermore, how
would I go about making these cells? Can I just weigh out a few
grams of randomly chosen amino acids, put them on a heating
plate for a few minutes, add water, and observe? Or is the
procedure more specific than this?
Clearly, there are several relevant follow-up points to the
claims that you make.
1. Where did the nucleotides come from?
2. As for these nonrandom sequences that are catalytically active,
what sequences are we talking about? What biological proteins
have these sequences?
3. What percent of the biological protein modules are explained
as being derived from thermal proteins (after all, most protein
modules are very old)? Has anyone resolved the 3-D structure
of a thermal protein?
4. The process of converting light into ATP is known as photosynthesis
in living cells. Only two main processes exist - the photosystems of
eubacteria (which employ an elaborate network of precisely positioned
chlorophyll molecules and Fe-S clusters) and bacteriorhodopsin, which is
found in one species of archaebacteria (and functions like vertebrate
rhodopsin). The thermal protein system is *homologous* to which one?
These questions seem very important, as I think most origin-of-life
researchers view thermal proteins as interesting chemistry in-of-itself,
but not very helpful in explaining the origin of the life forms that
exclusively dominate this planet (i.e., proteinoids might be somewhat
analogous, but are they homologous to life forms?)
>The information for doing all this comes from the amino acids and the
>resulting thermal proteins themselves, from their physiochemical structure
>and function. Davies couldn't bring himself to accept that the answer
>could be so simple, yet in science often the most profound mysteries turn
>out to have very simple answers.
Clearly, protein function follows from structure, which in turn follows
from the primary sequence of amino acids. But if this answer and
process is this "simple," why is life monophyletic? Why haven't new
life forms emerged many times over in the past 4 billion years?
Shouldn't we be able to find very different life forms existing today
that arose 1.5 billion years ago, 0.85 billion years ago, etc.? We don't.
Why not?
>The secret is that the complexity and organization of the universe
>is built up, layer by layer, from simple beginnings that have the
>ability to arrange and rearrange themselves in tremendously varied
>combinations. In other words, the information for life is already
>built into the universe when it first appears.
As I mentioned, I do indeed see the theological appeal behind this
suggestion and I cannot say it is wrong. But you seem to be overlooking
some things. Biological proteins hook up primarily through classical
peptide bonds, yet I seem to recall that the amino acids in thermal
proteins hook up in various ways. Thus, what would be the informational
source that specifies the use of only peptide bonds, especially when
thermals can do all the things you mention? Secondly, biological proteins
use only a specific set of 20 amino acids. Do thermal proteins
only form from this set or can they form from the hundreds of other
types of non-biological amino acids also? If they can only form from the
set of 20, your case is more appealing. If they can form from any
amino acid, you are missing another layer of specification.
I find your scenario to be interesting, but I think you are
overstating your case. The origin of life is not a problem of
coming up with "information", it's about explaining the origin
of the information that exists
Mike