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Re: Scaly tyrannosaurs; fact or fiction?



David Marjanovic wrote-

> Of course. Tyrannosaurs are definitely closer to birds than (to)
> *Sinosauropteryx*, and if I'm right, they're even closer to birds than
(to)
> dromaeosaurs + *Archaeopteryx*...

This isn't nearly so certain as you think.  Several analyses (Forster et al.
1998, Xu et al. 1999, my own :-) ) place tyrannosaurs just below
compsognathids in their analyses.  As for tyrannosaurs being closer to
neornithines than dromaeosaurids, well it's fairly unique, I'll give you
that.  Only Thulborn (1984) supported that as far as I know (even Paul
(1984, 1988)and Jackson agree dromaeosaurids are closer to birds).

Heinz Peter Bredow wrote-

> > > One of these days there will
> > > be some interesting news about a certain group of small ornithischian
> > > dinosaurs, but I really am permitted to say no more at this time.
> >
> > Any more information permitted for release now or do we have to wait
> > further?

Well, first of all Olshevsky's beliefs are due to his BCF hypothesis, which
is phylogenetically similar to the standard hypothesis, but has unknown
small feathery forms running around in the Triassic and Jurassic.  This
makes it more parsimonious to have insulating integument on small dinosaurs
of any type, including ornithischians.  Also, the statement was apparently
made the month Beipiaosaurus was described and was in part a defense as for
why that taxon would have such protofeathers when George still thought
segnosaurs were non-theropod.  So this could have just been a prediction of
his that would support his hypothesis.  On the other hand, if it was based
on a real ornithischian specimen, I'd be very interested ..... :-)

Mickey Mortimer