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labels are imaginary



     Time to vent my spleen.  Cladistic analysis is a useful tool in 
understanding phylogeny, but the whole cladistic system of naming things 
is in my opinion a little absurd.  
     Taxonomy and systemtics, cladistic or otherwise, is an attempt to 
uncover the phylogenetic relationships of living and extinct organisms.  
There is a concrete phylogenetic tree at the heart of the search.  If you 
say "these things evolved from these things", it is either true or false.  
It did happen that way or it didn't.  No one is 100% sure what that 
concrete phylogeny was, and everyone has thier own ideas, but the point 
is that phylogeny is not subjective.  Organisms are related in a certain, 
definite way.  
     Not so when you start assigning labels.  The names we give things, 
whether its "clade" or "family" or "outgroup" or whatever, are imaginary.  
They don't exist.  The only reason we come up with 
them is to help our own undertstanding of the way the phylognetic tree 
is put together.  You can say "birds are descended from dinosaurs" or 
"avain dinosaurs are descended from non-avain dinosaurs", but it 
doesn't really matter because you are saying the same thing,"These things 
descended from these things".   You could take any cladogram and modify it 
into a "kingdom-phylum-class..." phylogeny without altering the 
relationships of the organisms one whit.  You just draw the 
imaginary dotted lines in different places.  Whether you say 
"we are crossopterygians because we are descended from them" 
or "we are descended from crossopterygians but are different 
enough to call ourselves something different", matters not a whit because 
you have not altered the relationships of the organisms.
     The point I'm making is just that we assign labels only for 
our understanding.  So why say "avian dinosaur" and "non-avian 
dinosaur" when you could just say "bird" and "dinosaur"?  
Cladistics has created a convoluted naming system that 
does not clarify things any better than the traditional 
system.  Whats the point?                   

LN Jeff