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PALEORNITHOLOGISTS



A bit of talk on paleornithologists on the list lately with regard to 
their "boundaries". 

Nothing would prevent a (paleo)ornithologist from describing a 
dinosaur=>bird intermidiate, the real matter is whether they know what 
they are talking about.  Take for instance Feduccia's most recent book, 
_The Origin and Evolution of Birds_ (1996); Feduccia pretty much 
demonstrates his lack of knowledge on dinosaurs or any other archosaur 
for that matter besides neornithine birds.  He simply repeated a lot of 
what (somewhat more informed) critics have said on the dinosaur/bird 
link (a lot of Martin, a little Tarsitano).  Feduccia ignored or was not 
aware of any recent theropodian phylogenies that were available at the 
writing of his book (such as Holtz 1994).  Many of his criticisms were 
based solely on Gautheir's popular 1986 phylogeny.  Many of his (again 
from previous authors such as Hecht) criticisms are valid, such as the 
issue of the ascending process of the astragalus (is it homologus to the 
pre-tibial bone of birds?), but they do not take into account the more 
recent studies.  Like previous authors he ignores the evidence against 
his pet theory, the "thecodont"/bird link.  Feduccia thinks that 
disparate forms such as _Megalancosaurus_ and _Longisquama_ form a 
monophyletic group within the "Thecodontia", the "Avimorpha" (of 
Tarsitano), because they all have a presumed arboreal lifestyle and all 
show some SUPERFICIAL similiarities to birds (oddly, Feduccia ignores 
the fact that he is being a hippocrit).  I won't go into all of his 
statements because there are so many that have been proven wrong, but 
here is an example of somebody who shouldn't go into a field in which he 
is not familiar.  

Back to "boundaries"; I can easily go and write an entemology paper, 
which is something I am interested in, but given my poor knowledge in 
the area I shouldn't.  Take an another example: physist and sci/fi 
writer Fred Hoyle (who I believe is the primary advocate of the 
"steady-state" theory of the origin of the universe) and a few coauthors 
get into biology and paleontology with their claim that the Berlin and 
London _Archaeopteryx_ specimens were hoaxes.  Nothing prevents them 
from having or publishing such a viewpoint, all that counts is that 
their criticisms are valid, which they are not.  Most recently, I heard 
that they claim it is a "flying-reptile" without feathers, whatever that 
is.  

The field of bird ancestry is an old practice and there are many 
viewpoints.  To simplify, Tarsitano supports the "thecodontian" 
hypothesis, Martin and Whetstone (whatever happened to him?) support the 
crocodylomorph hypothesis, and everybody else but a few scattered others 
supports the theropod/bird link.  Of these authors, Martin knows the 
most about birds.  

However, few paleornithologists that I know of so such "flexibility", so 
I doubt that such a intermediate fossil will be described by a 
paleornithologist (other than Luis Chiappe or Larry Martin).  So the 
paleontologists have the edge.  

BCF

More people believe in BCF than before, but it still is a minority few.  
Until there is more fossil evidence, we cannot say that any theropods 
were secondarily flightless (we may say that some may have came from the 
trees).  

Matt Troutman

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