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No pennance for Pinnants

Message text written by "John V Jackson"

>>Well, as I've said a couple of times, I'm working from the Coelurosauria
tree in Mike Keesey's website.  Since I've never bothered to memorise
conventional trees (because I don't believe them) I'm not in a position to
say whether that tree is the one that you or most other people adhere to.
Well of course I can't help but feel insulted by this view of me, but I'm
sorry to say it doesn't come as a surprise anymore.  Far too many people,
when given the choice between putting it down to phraseology or to me being
a childish ignoramus, plump for the latter. People will continue see me as
it suits them to, and rationalise the evidence accordingly.<<

        John, I am sorry that you took umbrage with my statement...I was
not attempting to be insulting or derisive of you or your ideas in any way.
 I tried to make that clear in my initial post, and, as I apparently
failed, I offer my apologies.  All I was trying to do was to get a better
understanding of your perspective.  I tried to let you know how you seemed
to be coming across _to_me_ (and maybe to others), hopefully so that you
could alleviate my misunderstandings.  I do not dismiss your or anyone
else's ideas offhand without consideration; it was the point at which I
could _begin_ to consider them that I was trying to attain.  What I got
from your phraseology was that you were blithely ignoring other people's
analyses simply because their conclusions did not coincide with your own
(and given Matt Troutman's response to your post, I'm not the only one). 
My only question is:  is this interpretation correct?  Or have I missed
your point-by-point discussion of the characters used in other analyses and
your own, more parsimonious data set?

        Here's what I am understanding from your posts:  you have a
hypothesis of what characteristics a bird has as a result of being volant,
and how these characteristics change when these early birds became
flightless (producing various "theropod" groups).  Most of the anatomical
points you have put forth thus far arguing that all the bird-like theropods
must be secondarily flightless descendants of actual, true, volant birds
stem from functionalism within the initial hypothesis...is this also
correct?  If so, then the disagreement between yourself and others here
seems to be a debate between a Hypothesis-based Scenario and a
Phylogeny-based Scenario.  To be sure, both are valid and have much
scientific utility!  A classic example of a Hypothesis-based Scenario would
be Walter Bock's comprehensive (and quite logical)
arboreal-origin-of-flight hypothesis.  It's certainly had (and has) many
supporters -- although I'm not enough of a physicist to get into the
details of the theory, in concept I find that originating flight from the
trees down is much simpler than from the ground up.  Back when Bock
originally proposed it, the main fossil of contention was _Archaeopteryx_;
no other good early bird fossils were known, so the evidence was rather
ambiguous for how well _Archaeopteryx_ fit into both the arboreal and
cursorial origins of flight hypotheses.  Proponents of the cursorial origin
hypothesis used the actual relationships of _Archaeopteryx_ to assess its
preferred locomotory medium:  dromaeosaurids were perceived as the closest
relatives; they were perceived as cursorial, therefore _Archaeopteryx_ was
most likely a cursor, and flight probably originated from the ground
up...even if it _was_ more difficult (and yes, less parsimonious) than from
the trees down.  Bock's theory was elegant, but lacked good, physical
supporting evidence.  The phylogeneticists had the evidence and, as
difficult as it may have been to believe, disproved Bock's elegant
hypothesis.  (Yes, this is a grand oversimplification of the whole
arguement, but I hope it helps elucidate the nature of the argument).

        A similar thing seems to be happening here:  you are working from a
hypothesis, others (myself included) are working from the phylogeny
inferred from the fossils.  The phylogeny is testable...how can we test the
hypothesis?  And why would the hypothesis be more compelling in the face of
apparently contradictory phylogenetic evidence?  (These are serious
questions on my part, not snide remarks towards you or your ideas.)  

        Again, I apologize if you feel maligned by my previous post...I
wasn't trying to deride either you or your ideas...just get a better handle
on your position and why you are there.

           ____/_\,)                    ..  _   
--____-===(  _\/                         \\/ \-----_---__
           /\  '                        ^__/>/\____\--------
__________/__\_ ____________________________.//__.//_________

                     Jerry D. Harris
                 Fossil Preparation Lab
          New Mexico Museum of Natural History
                   1801 Mountain Rd NW
               Albuquerque  NM  87104-1375
                 Phone:  (505) 899-2809
                  Fax:  (505) 841-2866