Re: Behe book review: Pa. scientist again attacks evolution

On Aug 20, 7:09 pm, hersheyh <hershe...@xxxxxxxxx> wrote:
On Aug 20, 6:44 pm, Glenn <GlennShel...@xxxxxxx> wrote:





On Aug 20, 2:38 pm, hersheyh <hershe...@xxxxxxxxx> wrote:

On Aug 20, 4:40 pm, Glenn <GlennShel...@xxxxxxx> wrote:

On Aug 20, 11:20 am, hersheyh <hershe...@xxxxxxxxx> wrote:

On Aug 19, 9:38 pm, Glenn <GlennShel...@xxxxxxx> wrote:

On Aug 19, 5:44 pm, "Steven J." <steve...@xxxxxxxxxxxxx> wrote:

On Aug 19, 7:01 pm, Glenn <GlennShel...@xxxxxxx> wrote:

On Aug 19, 4:30 pm, noctiluca <robertlc...@xxxxxxxxxxx> wrote:

-- [snip]

Show us how ID can explain the supra-scapular ligament, benthic
structures, or anything at all. Keep in mind that "intelligence did
it" is not an explanation any more than "angels that look like Woody
Harrelson did it" or "wood nymphs did it" or even "Winnie-the-Pooh did
it." Intelligence is not a causal agency. Intelligence is an attribute
of some causal agency, just as generosity or spirituality or tone-
deafness might all be attributes of a causal agency. So in order to
demonstrate that ID can indeed explain anything you must be able to
show us the designer.

Tell it to Darwin, since in the absense of the knowledge of random
mutation and cellular function, natural selection isn't a causal
agency and can't even be imagined as one. Intelligence is most
definitely a mechanism, imbecile, just as generosity is as well. It
isn't necessarily the first cause, but then science doesn't require
knowledge of everything, or there wouldn't be need for science.

Given that Darwin *did* imagine natural selection in the absence of
knowledge of mutations or how cells function, your statement appears
to coexist somewhat uneasily with historic facts. To recognize
natural selection as a causal agency, one needs to note that [a]
organisms vary among themselves, [b] organisms pass on traits to their
descendants, [c] some of the variation among individuals is among the
traits that are passed on to offspring, [d] not all offspring survive
to reproduce themselves, and [e] some of these inheritable differences
cause some of the difference in which organisms survive to pass on
their genes. How traits are passed on, how new variations arise, and
how the mechanisms of inheritance interact with those of development
are good things to know, but one does not need to know them in order
to recognize natural selection.

Those are *observations*, not mechanisms. All you've said is "yuh
huh", without explanation. Without mechanism, natural selection is an
inference based at best on an inference, not on a mechanism, and not a
mechanism itself. Recognize that.

snip more long winded bull***

Are you agreeing that those observations are accurate?

Not sure what you mean by accurate, but I doubt the question has any
relevance. It isn't me you should question, but Darwin.

As to the mechanism of natural selection, it is clearly stated that
the environment sometimes (not always, neutrality and drift certainly
also happens) discriminatively interacts with and *causally* affects
the likelihood of one of two phenotypic variants to be reproductively
successful. That is, the environment is the independent variable
that, when it *causes* a *significant* difference in reproductive
success of one of two variants, is said to selectively discriminate
between the phenotypes or variants. There are any number of simple
experiments that can tell you whether or not a particular environment
has a significant effect on some metric of reproductive success.

You've recognized that "variants" exist. What mechanism explains this,
Darwin?

Darwin didn't know. But he did know, from his knowledge of artificial
selection, that new variants do arise in populations. That was common
knowledge of the time, certainly among naturalists, including Paley.
That was all he really needed to know: that it was a fact that
variation existed and a fact that new variation occurred and occurs in
populations.

That was all he needed to know for what? To explain variation?

No. As has been pointed out, variation in populations is a necessary
condition for natural selection to occur. No source of variation,
eventually no natural selection. One does not need to understand the
*mechanism* of variation (although we do now) to observe that
variation both exists and is produced from time to time in
populations.

You claimed that variation was all Darwin needed to know. I assume you
mean to form a theory of "origin of species".
Wouldn't the mechanism he described, natural selection, be seen as the
cause of variation?



That is, there are rather simple experimental tests that can determine
if a particular environment has a significant differential causal
impact on two variants. To take a simple example, mix together 50%
strep sensitive and 50% strep resistant bacteria and plate them in
growth media either with or without streptomycin. After growth,
determine the % strep resistant and strep sensitive cells and
determine if the difference is likely to be due to chance (or drift)
alone or requires a *causal* impact by the environment.

Please provide a reference to a similar experiment was performed by
Darwin, and what his conclusions were about mechansim.

As anyone will now tell you, Darwin worked with an erroneous mechanism
of inheritance (blending inheritance). That does not mean he was
wrong about variation existing in a population and variation arising
in populations. Knowledge of the details for how variation arises was
not necessary to understand how natural selection works.

Certainly a lack of knowledge does not provide a mechanism of
inheritance.
Describe how natural selection works without reference to a mechanism
of inheritance, Howard.

It is only necessary, for natural selection to work, that one be able
to recognize that there is some consistent mechanism of inheritance
(transmission of features from parents to offspring) in living
organisms. That knowledge already existed in Darwin's time, even
though an understanding of the precise mechanism did not. Although
more difficult in some ways, it is possible for natural selection to
work via Darwin's proposed mechanism of inheritance, wrong though it
was. But again, SFW. This is 2007, not 1857.

Oh no, variation of what exists isn't all thats needed. Shame. It may
be possible for something you might attribute to "natural selection"
to occur in the absense of a source of "new variation", but could not
explain evolutionary change.

I notice now that you appear to refer to natural selection as the
mechanism of inheritance. Is this wrong, or did you just not identify
this mechanism of inheritance?

In other words, in what way is it possible to
understand how natural selection works, being aware of but lacking a
mechanism of inheritance, in order to claim an explanation of
variation, diversity, inheritance, speciation.

The underlying requirement for natural selection does not require a
correct understanding of the mechanisms of variation or inheritance.
It does require evidence and knowledge that variation in populations
and inheritance of traits exist. That information was available in
Darwin's time. The precise mechanisms of variation and inheritance
are quite fully (if not completely) known today. And the increased
knowledge of mechanisms has largely supported Darwinian ideas about
natural selection.

No, the information was not available in Darwin's time to explain the
cell in the little warm pond to frogs. And the observations that
existed of inheritance coupled with natural selection didn't explain
it, nor are they capable of explaining it by themselves even now.

.

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