real life wrote:Setanta wrote:I would like for you to explain, bright boy, how you get a living organism in which RNA can originate, if there were no replicators to produce and propagate the living organisms.
Set, that would be a question for Dr Shapiro. And I encourage you to ask him.
I won't defend his thesis since I don't share it; he is more than capable of defending his own ideas.
This is just another example of how essentially dishonest you are. Shapiro's article answers that question, you just missed it entirely. Shapiro's article is only a commentary on a recently popular hypothesis commonly known as the "RNA world" hypothesis. That is all he addresses. His article does not provide any support for the idiotic claim embodied in this thread, which is to the effect that DNA (which is not what he is discussing) was "designed by a mind." Nothing in Shapiro's article supports such a conclusion.
You stated that DNA would break down in the ocean. Since Shapiro is not discussing DNA, his article does not support your claim. But more than that, Shapiro
is discussing the probable origin of RNA, and obviously considers RNA to be a precursor to DNA. Nothing in Shapiro's article supports the idiotic claim of this thread.
I only mentioned the spontaneous assembly of peptides and polypeptides in substrate clays because it is a good answer to the implication of your remark about DNA in the ocean, which implication is that life would have had to evolve from free-floating organic chemicals. Your feeble-minded attempt is to claim that there can have been no abiogenesis, because DNA would not have survived in the ocean to have given rise to life.
You completely missed the significance of Shapiro's argument (or have willfully ignored it.)
Quote:But I have previously given the same objection to the issue of propagation.
'If an organism DOES manage to put itself together, but lacks replicative ability , isn't the family line toast?'
His answer to the problem of reproduction is in the article. It is the 'garbage bag' scenario, and I find it pretty funny, (not just because it has a funny name.)
Shapiro's reference to a garbage bag scenario simply relates to his preference for a small molecule scenario in which the chemicals which would be successfully replicative are concentrated within cells in a random and chance manner by having gotten to big to pass the osmotic barrier of the lipids which form the cell membrane.
Shapiro nowhere suggests anything remotely like a statement that the "family line [is] toast" without replicability. In fact he specifically addresses how the small molecule model results in the replication of successful cells without reference to replicability, and only as a result statistical probability. The "garbage bag" concept, by the way, was originated by Freeman Dyson, not Robert Shapiro. (You can read about it at "edge.org/documents/life/Life.pdf"--i was unable to convert into a working link.)
Shapiro is essentially arguing that early replicators would have been energy driven, and therefore "unsuccessful" chemical combinations would have arisen again and again, and failed to result in replicators, while successful combinations would eventually have concentrated the molecules necessary to result in replicators. He is simply arguing that small molecule networks responding to energy stimuli do not need a "genetic" component; if they are successful chemical combinations, they will occur again and again, and that the evidence that this is so is the high order statistical probability. He argues against the "RNA world" hypothesis precisely because it is statistically improbable.
Robert Shapiro wrote:Systems of the type I have described usually have been classified under the heading "metabolism first," which implies that they do not contain a mechanism for heredity. In other words, they contain no obvious molecule or structure that allows the information stored in them (their heredity) to be duplicated and passed on to their descendants. However a collection of small items holds the same information as a list that describes the items. For example, my wife gives me a shopping list for the supermarket; the collection of grocery items that I return with contains the same information as the list. Doron Lancet has given the name "compositional genome" to heredity stored in small molecules, rather than a list such as DNA or RNA.
The small molecule approach to the origin of life makes several demands upon nature (a compartment, an external energy supply, a driver reaction coupled to that supply, and the existence of a chemical network that contains that reaction). These requirements are general in nature, however, and are immensely more probable than the elaborate multi-step pathways needed to form a molecule that can function as a replicator.
That second paragraph has already been quoted (Parados?), but its significance escapes you, because all you are interested in is quote mining efforts which you think will give a patina of scientific authority to the bullshit claims you make about the current state of life origins theory.
Shapiro is not arguing against the chance combination of chemicals which will give rise to
pre-RNA and
pre-DNA replicators, he is specifically arguing that statistically, that is most likely what would have happened.
Too bad what he wrote, which is rendered in very simple terms, shot right over your head. Were you engaged in learning, as opposed to just trolling for quotes which you think will look good when you make your feeble attempts to argue by inference for your poofism, you might have noticed that Shapiro is only arguing against an RNA first position, and not at all against the idea that life can assemble itself by chance from the chemical components and reactions which characterized the early earth.
Nothing in Shapiro's article supports the brain-dead thesis of this thread. Nothing in Shapiro's article even remotely supports a contention of poofism.
