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Re: OCCAM'S RAZOR & THERIZINOSAURS
>The morphospace consisting of only the characters "flying" and "nonflying" is
>one-dimensional (indeed, it has only two points).
A) I didn't buy this "morphospace" analogy before, and I don't buy
it now. I insist that you respond to my earlier posting on the subject
before you use it again.
C) Flying-flightless is a simple step my butt! If it's so simple,
how com flight has only evolved three times within the Vertebrata? Is it
only simple one way? If so, then your statement above is patently wrong.
G) As you yourself pointed out earlier, "bistate" characters are
usually a sequence of smaller characters. "Flying" vs. "non-flying" is about
as much a transition as "four-toed" vs. "three-toed". More, in fact, when
you consider the differing regimes of selection which each catagory encounters.
T) As some have observed, birds tend to become flightless in
environments which have been depleted of other fauna (e.g. islands). How was
it that successive groups of flighted theropods were more successful within
niches than dinosaurs which had had millions of years to adapt to those same
niches in the past? Was the Mesozoic just so different from today that
terrestrial niches lay open for the taking?
"BCF" is more than the hypothesis that all dinosaurs are secondarily
flightless. BCF is orthogenic, relies on unprovable assumptions about the
rate and timing of evolution, gross exagerations and misrepresentations of
"trends" in dinosaur evolution and evolution in general, very selective
character weighting and interpretation, a unique, personal and untestable
method of phylogenetic reconstruction ("Olshevistics"?), and deliberate
misunderstandings of concepts (the "spine of the cladogram", George?). All
of this is corroborated by my previous posts on this subject (available in
The idea that some or all dinosaurs are secondarily flightless does
have some merit, it is simply less parsimonious given the current evidence
and interpretations. BCF Olshevsky style has very little merit as a
scientific theory, and is beyond unparsimonious. Until George has something
new to tell us, something which actually does make sense, we should drop
this topic and move on to other issues.
Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
"...To fight legends." - Kosh Naranek