RE: eggshells, therizinosaurs & tyrannosaurs

["Ken Kinman" <kinman@hotmail.com>]

Thomas wrote:
> We do have to remember, though, that even within clades (such as Squamata 
> or
> Aves) you can get different shell structure morphology.
     But from what little I have gathered so far, these differences are 
just variations of the broader types.  The neognath bird type is apparently 
a distinctive variation of the ornithoid type.
     The overall ornithoid morphology is apparently distinctive enough to 
be of important phylogenetic value, one which I am surprised 
dinosaurologists don't emphasized more strongly.  To me this evidence seems 
more clearcut and less vulnerable to counterargument than something like 
digit homologies or even the semilunate carpals (ooops, probably will get 
criticized for saying that, but right now I am more impressed by the 
eggshells).
------------------------------------------------
> You mean "sensu Sereno".  Maniraptora sensu stricto is "modern birds and 
> all
> taxa closer to modern birds than to Ornithomimidae": see Gauthier 1986.
    I just meant that Maniraptora "sensu Sereno" is "sensu stricto" (in the 
least inclusive sense), whereas "sensu Gauthier" would be sensu lato (a more 
inclusive sense, at least using Sereno's phylogeny).
     Sereno does not seem to follow Gauthier's definition of Maniraptora, 
and instead uses a new clade name, Tyrannoraptora.  Apparently another case 
of cladistic disunity on what definitions to use!!??  In any case, I guess 
it would be better to say sensu Sereno (it would have admittedly been less 
confusing if I had said that).
                    Cheers, Ken Kinman
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