Reflectories
On Mon, 14 Aug 2000 12:09:26 -0700, Tedd Hadley wrote:
[...]
>SJ>But I wonder how true that assumption is? Even if it was granted
>>(arguendo) that the earliest bacteria consumed "prebiotic elements" (i.e.
>>raw amino or nucleic acids or their chemical building blocks), what
>>evidence is there that *modern day* bacteria consume such "prebiotic
>>elements" today? Most bacteria today consume the products of existing
>>biological activity.
>>
>>There are some highly specialised bacteria which consume some inorganic
>>products, but none, AFAIK, that consume raw amino or nucleic acids.
TH>You're apparently not aware that the putrefactive bacteria break
>down amino and nucleic acids. In the large instine, for example,
>these bacteria convert amino acids into toxic amines or ptomaines
>by decarboxylation (lysine -> cadaverine, arginine -> agmatine,
>tyroseine -> tyramine, orithine -> putrescine, histidine ->
>histamine.) The same or similar bacteria make short work of
>the veritable mountains of proteins left over when we "pass on".
>Putrefactive bacteria are found anywhere decaying plant or
>animal matter is found.
OK. Thanks to Tedd for furthering my education! :-) This was not my
major point, but nevertheless:
1) do we know that these "putrefactive bacteria" have always been around
from the beginning cleaning up any "amino and nucleic acids" produced?
2) are they anerobic, since there was presumably little or no oxygen around
for the first billion years? and
3) since there were no "intestines" around for the first billion years or so,
do these "putrefactive bacteria break down amino and nucleic acids" out in
the *outside world* in a completely abiotic setting?
[...]
>>TH>Where can you go on Earth today
>>>to escape life and still have the conditions for life? No where,
>>>it would seem.
>SJ>That might be true in nature but it is not necessarily true in a controlled
>>artificial setting, like a laboratory.
TH>Nature seems pretty much out of the question as a fruitful laboratory
>for abiogenetic expirements.
Even here I am not convinced. A complete mirror image D-amino acid life
form could emerge and existing bacteria might not be able to eat it?
TH>However, an artificial setting is a different story, yes. And,
>strangely enough, that's where abiogenesis research is taking
>place today :)
Tedd makes it sound like it is new. In fact a "abiogenesis research" has
been "taking place" in laboratories since at least *1953*, i.e. 47 years
(!) and no life has yet emerged spontaneously.
For a fraction of the cost of sending a mission to Mars to see if life
spontaneously generated there when conditions were once right, every
conceivable set of such condition could be repeated on Earth in a laboratory
and hey presto! life should emerge.
Yet if this has been tried it must have failed (otherwise we would know all
about it). And if it hasn't been tried, then why hasn't it?
Total failure of undirected abiogenesis is of course what ID would predict
and *not* what naturalistic prebiotic evolution would predict.
So if 47 years of failure is not a falsification of naturalistic prebiotic
evolution, how could it ever be falsified?
[...]
Steve
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"The firm step toward explaining the appearance of living things had been
taken. The elementary organic constituents required for the construction of
the big molecules, from which life subsequently developed, may be formed
spontaneously and easily. It seemed that once the first steps had been
taken, the others would have followed easily. Research scientists threw
themselves unhesitatingly into the frenetic race to be the first to synthesize
living matter in the laboratory; but so far no one has succeeded. There are,
in fact, many thresholds to be crossed. Life is based upon two mutually
interactive systems, one of which makes provision for growth and the other
for reproduction. The systems are also interdependent, and neither may
exist without the other. Which was formed first? The answer that they were
formed simultaneously is too simple to be acceptable. The problem of how
the first living organism was formed has still to be solved." (Minelli G.,
"The Evolution of Life: The History of Life on Earth," [1985], Facts on
File: New York NY, 1986, p.5)
Stephen E. Jones | sejones@iinet.net.au | http://www.iinet.net.au/~sejones
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