Re: David Deamer's Ideas

Tom Hendricks wrote:

"We have to face up to the biophysical facts of life," Deamer said.
"Hot, acidic hydrothermal systems are not conducive to self-assembly
processes. But these results serve to guide us to other possible sites
that might be better choices...."

This sounds to me like another blast against the ventists.

As far as I know it is not true, though - e.g.:

``Hydrothermal systems might be the place to look. They
are being increasingly invoked as sites for ?the origin of life?
(Holm 1992; Russell and Hall 1997), and they seem especially
good places for the earliest stages of the kind of evolution
we are trying to imagine. Layer silicates, for example,
grow and dissolve relatively quickly at moderately high
temperatures and pressures.''

- http://www.elementsmagazine.org/Elements_online/ELEM_V1n3.pdf

Deamer is incorrectly generalising from the failure of his bucket
of slime to "self-assembly processes" here.

Membranes are not the only thing that can self-assemble.

IMO, membrane self-assembly is irrelevant to the problem
of the origin of life - since the first living things were
most likely naked genes - and membranes probably came in
much later - after at least one genetic takeover.

Most of the supposed roles of membranes in holding early
organisms together, stopping them getting washed away,
concentrating molecules, etc are all performed quite well
on mineral surfaces - where a membrane would mostly get
in the way.

Membranes would have been needed /eventually/ to
facilitate some long-distance dispersion strategies
and to allow greater complexity - but such features
would have come in later.

Only one type of self-assembly process in nature is
known that is capable of making high-fidelity copies
of information in prebiotically-plausible environments.

Since evolution actually /does/ depend on the
reliable copying of information, that is the
obvious place to look for the origin of life.
--
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