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RE: FEATHERS FOR T-REX?
Ken Kinman wrote:
>As for Plesion Alvarezsaurus, it
>too seems to be in this same early maniraptoriform part of the tree (and
>probably therizinosaurs as well, although many people seem to have
>difficulty accepting that possibility).
I think "many people" have difficulty accepting the way in which this
proposition was advanced. It was done so by ignoring or overriding studies
that link _Alvarezsaurus_ to mononokines on the basis of a long list of
derived characters . No data was offered by you in support of your
alternative phylogeny; it's all based on a "hunch".
I, for one, accept the possibility that Alvarezsauridae is polyphyletic. I
also I accept the possibility that tyrannosaurids could be secondarily
flightless birds (avialans). However, at the current time, the available
evidence does not point in that direction.
>And it will help cushion the
>shock if Mickey's analysis demonstrates the non-holophyly of
As Mickey himself has often said (more times than he would probably care to
remember), there is abundant scientific literature already available to
support a monophyletic Alvarezsauridae. There is no reason why you should
hold out in the hope that somebody, somewhere, will come up with a phylogeny
that corroborates your personal opinions.
Tom Holtz wrote:
>While in general I would agree with this, but I do want to remind people
>that giant ground sloths included bear-to-elephant sized animals that
>lived in a wide variety of environments, including the tropics, and as >far
as we know they were all very hairy.
Ditto for the marsupial megafauna of Australia.
Timothy J. Williams
Iowa State University
Ames IA 50014
Phone: 515 294 9233
Fax: 515 294 3163