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Re: On the subject of "arbitrary" paleontology



Philidor@aol.com said:
"These are two different procedures [I had said experimental
scientists re-ran chemical analyses over and over, while historical
scientists looked at the same defined characters as the original
researcher], one data gathering, the other reviewing a 
hypothesis.  Also, don't different scientists look at different
characters, 
searching for monophyly?"

Okay.  First off, I apologize for not making my sentence more clear. 
You are right, different scientists will sometimes utilize different
characters, but usually these are added to what has already been
previously demonstrated as reliable characters.  If we were all using
different characters to substantiate our hypotheses, the system would
be much less reliable -- but this would be readily apparent by the
several different, non-agreeing trees that would be produced.  Also,
this would preclude testability, as each person would be re-inventing
the wheel.  However, this is not what is happening, and usually
researchers are adding to already defined character sets.  As I
emphasized before, the consensus is remarkable.

To continue:
"On repeatability, though, when 'cold fusion' was discovered or the
sheep was 
cloned other scientists did not ask for the lab notes or even the
sheep.  
They asked for the recipe which would allow them to do the same thing
in 
their labs.  The concern is repeatability of the process of making
something. 
 As you say, we cannot 're-run evolution again and again'.  One of
the 
'constraints and problems' is the absence of this kind of
repeatability."

Er, here again I think you are displaying a bias toward experimental
procedures in science, rather than the scientific method itself.  The
problem is, most of us are exposed only to experimental science
procedures in school but never how such things are done in the
historical sciences of paleontology, archaeology, anthropology, and a
number of other areas.  Yes, I agree, we cannot re-run evolution.  But
there are "recipes" in historical sciences, just of a different
nature.  The digital (0101010) data from cladograms is a recipe. 
Other researchers can re-run that hundreds of times if they doubt the
sincereity of the publishing researcher.  Or they can read the
"recipe" of how each character was chosen, and investigate individual
characters for themselves, again bringing with it repeatability.  Were
paleontologists to run the provided cladogram data and come up with
strange new cladograms, or even minor variants not address by the
publishing researcher, his/her results could very well be falsified.

Statistics can be used in paleontology to discern morphometric or
shape differences between different fossil animals.  Principal
components analysis, multivariate statistics, thin-plate splines, warp
analysis, and a number of other techniques can and have been used to
differential morphological and functional differences between groups
and taxa, this statistical data also being published and available as
a "recipe" for repeatability.

We must get away from viewing the scientific method strictly as
performing controlled experiments in labs following formulas.

Further:
"Assuming that the original interpretation was logical and included
all of the 
available data, 'a re-examination of already collected material'  is
not as 
significant a danger as changes in the data itself."

I beg to differ.  Sometimes material sits in collections for decades
without being touched or examined.  Upon examination of materials in
drawers or on shelves, new information can be uncovered.  With the
entry of cladistic analysis into paleontology, old bones were examined
again in new light, destroying many long-held hypotheses on
relationships and functional morphology.

And futher:
"I don't have the knowledge or experience of the people who decided
to use 
parsimony as a way to evaluate theories.  However, the need for
something 
like parsimony in forming judgements does show that the data itself
is 
insufficient to support/refute theories."

Parsimony is an assumption used in all science, not just
paleontology.  For instance, we come to a section of the stratigraphic
column where, as we go up (which should be from older to more recent
rocks) we begin to find fossils and flora that went extinct BEFORE the
animals we find underneath them.  Is it possible that the entire fauna
and flora we're finding represent a re-emergence of an earlier system,
causing fauna that we usually find after them to go extinct?  Is it
possible that reports of the extinction of this early fauna and flora
everywhere else is incorrect, despite the hundreds of sections done? 
Or could it be simply that the rocks have folded back on themselves
and overturned, creating the illusion of an ancient system springing
back to life?

The most parsimonious explanation here is the last one.  And it can
be checked against the stratigraphic column in that region and all the
other regions where this fauna and flora occur.  The use of Occam's
razor isn't a mis-giving about the method.

Finally:
"Evolutionary biology hasn't completely sorted out the 
mechanism-related issues of mutation, selection, etc., has it?"

Unless I'm gravely mistaken, the answer is almost completely yes.  We
still do not understand many fine scale details, but I'm unaware of a
biologist or paleontologist who does not think the mechanism by which
inherited change happens is through the genetic makeup of DNA.

I said you will never have complete objectivity or agreement in
paleontology, but this is an observation for all sciences.  Until
recently, no one knew what a black hole looked like, but it was
postulated that they were there based on indirect evidence.  None of
us are omniscient, nor should we pretend to be.  I agree with you
completely that there are biases and that some (and sometimes many)
scientists cling to theories or hypotheses they like or our
comfortable with (including me -- I have favorite theories,
warm-blooded dinosaurs and asteroid extinction being two).  However,
the error-correcting machinery of science (to borrow from Carl Sagan)
keeps us honest and eventually negates those who do not relinquish
their positions in light of new evidence.

Skepticism, like the kind you valiantly display, is what science
thrives on, and nothing (perhaps laws?  but probably not) is safe.  As
a rule, when someone in science presents a hypothesis, many other
scientists attempt to tear it down.  By doing so, we find out (quickly
or in the long run) whether a hypothesis is worth its salt and whether
it is false.  Whatever shred is left over, no matter how tiny, that
can withstand peer review and skepiticism helps bring us that much
closer to the reality -- the reality of what happened 150 million
years ago to a group of dinosaurs or at the "big bang" or what a drug
interaction will be.

Matt Bonnan
NIU