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Re: Theropod herbivory - parallel evolution or one clade?
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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