Re: Theropod herbivory - parallel evolution or one clade?

[dinoboygraphics@aol.com]

Tim Williams wrote: "If _Incisivosaurus_ is a herbivore, as interpreted 
by Xu et al. (2002), then herbivory/omnivory may be primitive for the 
Oviraptoriformes. Given the suggestion that troodontids may have been 
omnivorous, this dietary preference may be primitive for a much wider 
group, like Maniraptora. Maybe the immediate ancestors of birds were 
omnivores, and began climbing trees in order to nibble on leaves? Many 
evolutionary scenarios have focused on the possible role of predation 
in the evolution of avian flight, but a possible role for herbivory has 
received far less attention, AFAIK."

Only derived troodontids have teeth with large dentical that are 
suggestive of ominory; basal troodontids have smaller serration and in 
some cases more recurved teeth.  Given dromaeosaurs and predaceous 
basal troodontids, it seem unlikely to me that herbivory is primitive 
to paraves...but stranger things have happened.


Scott Hartman
Science Director
Wyoming Dinosaur Center
110 Carter Ranch Rd.
Thermopolis, WY 82443
(800) 455-3466 ext. 230
Cell: (307) 921-8333

www.skeletaldrawing.com

-----Original Message-----
From: twilliams_alpha@hotmail.com
To: dinosaur@usc.edu
Sent: Thu, 16 Nov 2006 6:06 PM
Subject: Re: Theropod herbivory - parallel evolution or one clade?

David Marjanovic wrote:Â
Â
> That's an understatement. Since its description everyone seems to 
agree >*Incisivosaurus* is the basalmost known oviraptorosaur. The 
oviraptorosaurs >and the segnosaurs seem to be each other's closest 
relatives, so there is a >relation.Â
Â
Sereno erected the name Oviraptoriformes for the 
therizinosaur-oviraptorosaur clade. _Incisivosaurus_ and 
_Protarchaeopteryx_ (if they are not one and the same) are both 
regarded as basal oviraptorosaurs. _Shanyangosaurus_ may belong here 
too, or as a basal oviraptoriform.Â
Â
If _Incisivosaurus_ is a herbivore, as interpreted by Xu et al. (2002), 
then herbivory/omnivory may be primitive for the Oviraptoriformes. 
Given the suggestion that troodontids may have been omnivorous, this 
dietary preference may be primitive for a much wider group, like 
Maniraptora. Maybe the immediate ancestors of birds were omnivores, and 
began climbing trees in order to nibble on leaves? Many evolutionary 
scenarios have focused on the possible role of predation in the 
evolution of avian flight, but a possible role for herbivory has 
received far less attention, AFAIK.Â
Â
CheersÂ
Â
TimÂ
Â
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