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Coelurus a maniraptoran (for how long?)
Tom,
I guess I should have said that I don't recall you recently placing
Coelurus in Maniraptora "in print". In your DML post below (in January),
where you say Coelurus is "further up the tree", I didn't take it to mean
all the way up into Maniraptora.
And compsognathids were at the same time jumping several nodes in the
opposite direction like acrobats in a circus. How confident are you that
they won't switch back again in next year's cladogram (with compsognathids
going back up into Maniraptora and Coelurus going back down near
Ornitholestes)? And with tyrannosaurs jumping around (and who knows what
troodonts might do next), I'm not sure the maniraptoriform or maniraptoran
boundaries are very useful anyway (except to keep ornithomimids stationary).
The ornithomimids are going to get dizzy with all these groups
leap-frogging back and forth overhead in both directions.
I was rather taken aback when you said this morning that it "doesn't
matter what other taxa belong in there." It does matter to a lot of us.
Is sacrificing stability of content in the name of "stability of definition"
really the best path to a more stable nomenclature? Lots of people
obviously don't think so, and anchoring down one genus (even Ornithomimus)
in the midst of all these cladistic jumping beans appears to have been
rather premature. This makes "waiting for papers" even harder, when they
are already out-of-date by the time they appear.
Guess I'd better just stick with a coelurosaur clade (which really
does have a consensus "content"), and I will no longer use
"maniraptoriforms" and "maniraptorans" even informally, because they may or
may not include tyrannosauroids, compsognathids, Coelurus, Scipionyx,
Bagaraatan, and many others (even Proceratosaurus??). Why has
Neocoelurosauria fallen out of usage when it seems to have a far more stable
content than Maniraptora or Maniraptoriformes? Has Neocoelurosauria been
cladistically defined? If I sound a little aggravated, I am---but just wait
until BANDits start in on PhyloCode when it is implemented. That's when
things are really going to hit the fan, and my complaints will seem bland in
comparison.
----Ken
*******************************************************
Jan. 8, 2001, Tom Holtz wrote:
In my Gaia paper compsognathids do fall out as basal maniraptorans; in
a modified version of the same matrix in the forthcoming Ostrom symposium
volume, they fall out equally parsimoniously as basal arctometatarsalians
or basal maniraptorans; in the SVP 2K matrix, they fall out again as basal
coelurosaurs (indeed, one of the basalmost clades, with forms such as
_Ornitholestes_ and _Coelurus_ further up the tree).
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