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FW: Post-SICB Report: a couple more (long) thoughts




-----Original Message-----
From:   Jeffrey Martz [SMTP:jeffmartz@earthlink.net]
Sent:   Friday, January 15, 1999 11:38 AM
To:     'Dinogeorge@aol.com'
Subject:        RE: Post-SICB Report: a couple more (long) thoughts


Dinogeorge wrote... 
>The key problem with cladistic analysis is that it is >inherently<
>unfalsifiable. You have a character matrix, you have a computer with
> appropriate software, you plug and chug, and voila, a cladogram 
> appears. How  do you >know< that this cladogram is the True 
> Cladogram for the group? Or to  put it in Popperian terms, how can 
> you tell whether it is wrong? Suppose it doesn't accord with, say, 
> biogeography or stratigraphy 

[Jeffrey Martz]        
     Because our knowledge of the biogeographic and stratagraphic distribution 
of organisms is as constantly expanding and changing as cladograms.  How papers 
come out that start with "first occurrence of blah blah in..." or "oldest 
known..."?  The extent of the biogeographical and stratagraphic knowledge to 
date isn't neccessarily as reliable in giving the whole picture as our 
knowledge of character states in fossils.
 
> or functional anatomy or physics? 

[Jeffrey Martz]  
      When does cladistic analysis contradict functional anatomy?  HOW could 
cladistics contradict physics?  Or are you being facetious?

> I think the principal problem that many paleontologists have with 
> cladistic analysis is that cladistics is not reliable enough to command > 
> priority over  biogeography, stratigraphy, functional analysis, physics, > 
> and the other methodologies in the paleontologists' toolkit... 

[Jeffrey Martz]  
     But neither do those tools command cladistics, because they too may be 
lacking or incomplete.You ask when the fossil record is "good enough"; when the 
the biogeography and stratigraphy "good enough"?  It may indicate when and when 
an organism WAS present, but doesn't neccessarily indicate when it WASN'T.  
This is probably where most of the "conflicts" of biogeography and stratigraphy 
with cladistics arise. 
     Cladistics is just one tool, but it is still an extremely useful tool.  I 
think cladistics is useful primarily because it makes it easier to see the same 
patterns and similarities that paleontologists have always used to group 
organisms. It is not infallible, but neither should it be discarded out of hand 
because the biogeographical and stratagraphic evidence isn't complete (and 
never will be).

LN Jeff