alt.education

I'm worn out from responding to another post, so I'll refer you to that
discussion, and just hit the high points here...

On Sun, 02 Mar 2008 14:16:14 -0500, Bob LeChevalier wrote:

> racqueteer wrote:
>>On Sat, 01 Mar 2008 17:06:17 -0500, Bob LeChevalier wrote:
>
>>>>A far better comparison would be to string theory,
>>
>>Science is not FACT; it is instead a set of models that attempt to
>>describe the world around us. Those models are subject to change, and
>>have routinely done so in the past. Some of our models are very good,
>>and may, in fact, approach being "true". Our model for the evolutionary
>>process is one of these, as is germ theory. Other models have been
>>incomplete or even flawed. Science demands that models be continually
>>tested, the presumption being that they may NOT be completely correct,
>>and modified where required, in an effort to make the models USEFUL.
>>This is not an indictment of science, it is the NATURE of science.
>
> Agreed.
>
> I think that it is almost certainly true that abiogenesis did happen,
> there being no evidence for any other mechanism, and Occam's Razor
> requiring that we not introduce any new entities unless they are
> demonstrably evidenced or necessary. But we do not as yet have an
> agreed upon model for how it happened, so abiogenesis remains at best a
> family of related hypotheses.

Whether you or I believe it is somewhat irrelevant. As someone trained
in science, I'd kind of like to see it happen at least once before
completely buying into the idea.

>>Again, imo, I believe science requires some testable way of attempting
>>to falsify the model, and I'm not sure how one does that for
>>macroevolution
>
> http://www.talkorigins.org/faqs/macroevolution.html#falsifying (which
> has a further pointer to
> http://www.talkorigins.org/faqs/comdesc/
>
> answers this far better than I can.

Fair enough, I haven't the energy to look at this now, but copied down
the cites.

>>While mutation of EXISTING genes (or turning them on or off) seems,
>>based on recent evidence, to be capable of producing morphological
>>change sufficient to result in "new organisms", doesn't that mean that
>>our original single-celled organism had to possess all the dna and gene
>>structure of present-day organisms (you can't mutate what isn't there)?
>
> Yes and no. DNA is a variable length string. Many mutations change the
> length, either adding to it or subtracting from it. "Gene structure"
> arises from a particular DNA pattern proving to be workable and stable.
>
> There is presumably some minimum length chain of DNA necessary to
> produce all of the functions we associate with "living". Once that
> exists, there is no reason why mutations couldn't get from there to
> however many base-pairs there are in the human genome, just by simple
> addition of copies which then evolve independently.

Hmmm... I have to admit I've never heard of base pairs or genes
"evolving" before. What does that mean in this context? It may simply
be that I am ignorant of the finer points of genetics, but here is my
problem: I have a simple organism, one of a kind, the only living thing
that exists. It contains 'x' amount of genetic information (where that
information came from in the first place being somewhat vague, but
possibly by combining simple strings of chemical material found in the
pool).

Somewhere along the line, one of its descendants incorporates entirely
new information into its genetic structure resulting, presumably, in a
longer chain of dna. How, and from where? Maybe it grabbed up some more
of those strings of chemical material? Have we observed that? Do we
know that the same sequence (chain) results in different expressions
depending on its location in the dna chain?

> I suspect however, that there was some form of inefficient replication
> involving RNA chains before there was a DNA chain, so probably the first
> life with a DNA chain was already far more complex than the simplest
> possible chain to enable life.
>
>>If not, then one needs to demonstrate a case where NEW genetic
>>information is generated from one generation to another.
>
> Every mutation that adds base pairs adds new genetic information.
> Viruses do it do us all the time.

I would maintain that this is not new genetic information (at least in
the case of viruses). How, exactly, does the mutation result in the
addition of base pairs, and where does the material to construct them
come from? You're obviously better informed on this issue than I am,
Bob, as I have more questions than arguments. If you're willing to take
a stab at explaining, I'm certainly willing to listen.