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Re: BIRD STUFF AND CLADISTICS



<<Sorry, BCF has very, very little to do with cladistic analysis.>>

I did not say that BCF had anything to do with cladistics.  I did say 
that your hypothesis seems to be based on the intuitive method employed 
by bird wrokers like Olson and Feduccia.  

Now, the intuitive method does seem to agree with cladistic analyses in 
many cases, such as in the two seperate pelecaniform phylogenies prduced 
by Olson (intuitive school) and Cracraft (very cladist).  Though recent 
molecular studies (which can be just as unreliable and subject as 
phylogenetic studies) by Sibley and others suggest that Pelecaniformes 
is polyphyletic, I think that the two phylogenies are a very strong 
framework for future studies (which I think are being done by members of 
this list). 

<<It does have much to do with interpreting phylogenies that cladistics 
or any other method might come up with. BCF is much more functional 
analysis than taxonomy or phylogeny, and can be applied to any suitable 
cladogram of the theropods (even, for example, the ones currently 
enjoying majority support among dinosaur paleontologists).>>

BCF is a wonderful hypothesis from a functional standpoint and I agree 
with many of the points, but not all.  For one, in your 1994 Omni 
article you claim that BCF has a leg up on the traditional dinosaurian 
classification because it is able to classify the enigmatic 
_Longisquama_, _Megalancosaurus_ and _Cosesaurus_.  This is very 
phylogenetic in my point of view and very similiar to the intuitive 
approach because it relies only on the facts (which may be subject to 
change) that these creatures look birdlike, are archosaurs or near 
archosaurs, share some theropodian characteristics, and fit well into 
your scheme of BCF.  This reminds me greatly of the 'fossil-mosaic' 
argument used by many intuitive workers.  

<<Also, since I haven't published my phylogenetic analyses yet (I have 
about 50 pages of manuscript on just the stegosaurs, for example), how 
do you know >what< they're based on or how tenuous my methodology is? 
>From my brief and occasional comments on this dinosaur list? I claim 
that your statement here is far more tenuous than my methodology is. 
You're talking through your hat here.>>

Most of what I have on your hypotheses is what you have posted on this 
list and have heard from you in very occasional private email (so please 
publish!  I think that the scientific world would benefit greatly from 
any number of your ideas whether or not they are accepted or not).  But, 
since you obviously do not place much faith in cladistics (from I can 
gather), I think it is reasonable to assume that you produce phylogenies 
similiar to the way that intuitive systematists do.  Now, I must 
emphasize again that I do not like cladistics as much as many 
systematists do and I do think that other factors, such as behavior, 
life-history, etc., should be considered more in phylogenetic analysis.  
The aforementioned factors can (and most often do!) produce a phylogeny 
that agrees with morphological and molecular studies without applying 
strict cladistic principles.  However, I think that cladistics, is much 
more reliable than phylogenies based on intuitive methods for the most 
part, even though we have really nothing to base this on because the 
perfect phylogeny will never be found.  

Matt Troutman 
m_troutman@hotmail.com


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