

Re: Theropod herbivory - parallel evolution or one clade?

David Marjanovic wrote:

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.

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.

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.



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