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Re: Tyrant stuff (no longer ranting) (was RE: Rant (was RE: Details on SVP 20...

George Olshevsky (Dinogeorge@aol.com) wrote:

<Yeah, yeah. This and that prevented this and that. This is handwaving, 
period. Why not look more seriously at the idea that there was no land 
connection across the Bering region for circa 20 million years, before 
concocting all kinds of explanation to justify cladograms that could well
a  priori be flawed?>

  The data, including faunal constansy between the two continents during
time, appears to argue against absence of land connections following the
Turonian. In fact, it is such faunal interchange that supports the land
connection, and for this matter, its the same type of data that supports
the Great American Interchange that allows us to identify the SA
sabretooths as *Smilodon*, and with several phorusrhacids in NA, along
with sloths, camels, etc., and the presence of the originally-Asian
Columbian mammoth in northern South America. Applying the same data argues
that a faunal interchange is more likely, whatever un-presented arguments
of phylogeny in a few taxa might say. And this still does not tell us how
*Catopsalis* is in both Hell Creek and Nemegtian sediments, unless they,
too, to fit the idea that there was no land bridge are another,
non-dinosaurian, form of convergence that has deluded us all (not likely,
but possible), and just another way to explain away similarities in
otherwise "impossible" sister taxa. If there was no land bridge, they
could not possibly be related as closely as everyone else thinks, and
therefore they weren't the same genus, and we would have to find some
Turonian ancestor for *"Tarbosaurus" efremovi*, even if someone allies
them to "albertosaurs" instead (note that there are no identified
"albertosaurs" previous to the Campanian).


Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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