Darwinian and panbiogeographic frameworks

[Stuart G. Poss]

John Grehan wrote:

> My feeling about these matters of evoltution is that they are more complex tha
n
> simple tests of individual hypotheses so its not possible to reduce the
> research activity to this simple criterion. What might constitute evidence
> that cannot be explained by a theory might not be regarded the same way
> by someone else.

Cases in which no explanation is possible because there are simply "too many
independent variables"to defy solution will always beyond the reach of science.
 If
one's evidence is so elusive as not to permit its
assessment it is difficult to understand the utility of the tests you propose we
make instead.  In any event one should strive to reduce unnessary complexity of
one's hypotheses in the absense of reasons to the contrary.   It is for this rea
son
that the theories of Darwin and Einstein are so powerful.  They are simply enoug
h
structured to permit their test but remain of considerable explanatory power.

> It seems to be to be the nature of the Darwinian research program that it can
> explain anything and everything.

This charicature is often made of Darwinian theory, but nothing could be further
from the truth.  There are a great many specific circumstances, which if true wo
uld
falsify the theory.   Find just one organism that foregoes its reproduction unde
r
all circumstances to benefit that of another bearing wholely unrelated genes and
the entire theory vanishes.

> I guess I look at the "evidence" as someting that is a matter of
> interpretation. For
> someting to constitute "evidence" is a matter of interpretation so I see no
> difference
> between evidence and interpretation. Perhaps an inconsequential difference.
>

This may explain your inability to choose among the outcomes of your tests.

>  The difficulty with the
> requirement
> of demonstrating this criterion is that one might always come up with an
> ad hoc hypothesis to disqualify the disproof as disproof.

Certainly the joy of science is that we can endlessly test our best ideas, the
extent to whichhypotheses are "ad hoc" depends on the extent to which they are
necessary to the theory.
If they are completely unecessary, I would agree they they could be termed "ad
hoc".  However,
I find few scientists are sufficiently interetested in wholely non-essential
speculation to conclude
that there is a utility to an endless series of ad hoc hypotheses.


> I repeat, I said my understand was that he did not observed the differential
> selection. You concur by stating that he observed the results of differential
> selection. Quite a different thing.

Not necessarily different if the process is a continuous one.  If you observe
theresults or consequences of a series of events, one might reasonably infer tha
t
such events occured.

>   However, his observations with regard to differential selection taking
> >place among these birds remain largely verrified by subsequent evidence,
> >in this
> >case a variety of beak lengths, not to mention a consistent pattern of
> >change in
> >allelic frequencies.
>
> I have no problem with the possibility that the differences may be the result
of
> selection and that investigators have made a good case for this.

You implied earlier that such might not be the case, so I was compelled to take
issuewith your statement.


> You have just stated the misrepresentation. The view that orthogenesis is
> teleological
> has been supported by some of its practioners, but in general it has not.
> The teleological
> assertion was made by Mayr, Eldredge, and Gould to name a few. Teleology was n
ot
> asserted by Haacke, and neither by other supporters of the model.
>

Well, actually I derived it from a definition found in the American Heritage
Dictionary of the English Language,which my knowledge of the theory and its
historical discussion and its rejection is consistent with my understanding of
contemporary useage.  If one alternately defines orthogenesis to so that it
includes the notion that the descent of organisms is not independent of their
natural environment, I am having difficulty in understanding how your theory of
"orthogenesis" is different from that proposed by Darwin in which selection is t
he
arbitor of survival of hereditable differences.

> That is not the point. The point is that the observation was unknown even
> at the time it was predicted.

What observation?  If its unknown how can I discuss it?

> Non-Darwinain biogeography made the prediction,
> Darwinian biogeography did not.

Again I ask, what specific prediction?

> I, since the fundamental correctness of his
> >thesis both preceeded and suceeded him.  His conclusions are as true today as
> >they would have been 100 million years before he was born.  We can expect the
y
> >will be true tomorrow.
>
> And one might assert that without understanding orthogenetic mechanisms
> would could not expect to fully understand structure and function.
>

Yes, but one would be incorrect.  Again, I ask.  What mechanisms in what systems
?

>
>
> A scientist should in principle should always want to impose their best
> >(most predictive) theories (or those of others that he/she finds correct) on
> >their colleagues for their own good

> For their own good? I try not impose. I am more interested in exploration for
> my curiosity, and to make the view known for those who wish.

Seems to me we are doing someone who still believes the earth is flat a favor by
correcting his errent thinking.

> Consequently, some generosity toward the sincerity of our colleagues
> >efforts to "hawk their scientific wares" is in order, even though we may
> >in some
> >cases feel that they have nothing to sell us that we are interested in buying
.
>
> Again, this appears to be a difference in persepctive. I'm not in the market
> for "selling" my view, just sharing it with those interested.
>

One might argue that the seemingly unstopable logic of capitalism, scientific
rationality, and natural selection is that iideas that are interesting but not
widely valued and utilized to advantage are not likely to be of much permanence.
While I too like to share my views, how can I reasonably expect my interesting,
but
unconvincing ideas to be regarded as of much consequence.  In any event, I find
it
useful to strive to make myself my own toughest customer.

> John Grehan



--
_____________________________________________________________________
Stuart G. Poss                       E-mail: Stuart.Poss at usm.edu
Senior Research Scientist & Curator  Tel: (228)872-4238
Gulf Coast Research Laboratory       FAX: (228)872-4204
P.O. Box 7000
Ocean Springs, MS  39566-7000