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Re: Epidexipteryx



Or just among maniraptorans in general. Not many avians are
hypercarnivorous, either.

Yes, true. But archaeopterygids may have been, so I thought I'd limit my generalization to non-avian maniraptorans.

Given their size, I find it hard to not imagine lots of insects in their diet.


However, there's *Shenzhouraptor* with the gingko fruits in its stomach, and then there's *Omnivoropteryx*. I suppose those are why Lindsay Zanno simply declared the birds ancestrally omnivorous in her talk without further comment. As far as I remember, she used up her whole 15 minutes, which means there was no time for questions.

I avoided citing "noncarnivory" as a maniraptoriform trend because some phylogenetic analyses recover predatory theropods such as _Ornitholestes_, compsognathids, and even tyrannosaurids inside Maniraptoriformes (i.e., closer to birds than ornithomimosaurs are).

Her own analysis seems not to.

There's _Boluochia_ of Early Cretaceous (Barremian) age, which had a hooked beak and so might have been predatory.

And then there are all those avisaurids with big claws in general and a very big claw on the 1st toe in particular. Strongly curved claws, too. No skulls known.


Darn, wish I'd seen Lindsay's talk. (Sadly, I wasn't at SVP either, but Bristol is looking promising.)

Here's the abstract:


The phylogeny of Therizinosauria (Theropoda: Maniraptora): Implications for the evolution of coelurosaurs

The past decade has witnessed a surge in our knowledge of therizinosaurs.
From their once poor fossil representation, these bizarre raptor dinosaurs
[!] are rapidly becoming one of the most diverse theropod clades, with at least 14 species arrayed across Asia and North America. Within the past eight years alone, more new therizinosaurs have been described than were known during the preceding half century of paleontological research. Once a topic of controversy, the broad phylogenetic relationships of therizinosaurs have recently been substantiated by the discovery of "transitional" Early Cretaceous forms (e.g. *Beipiaosaurus*, *Falcarius*) whose anatomy indicates a clear ancestry among maniraptoran dinosaurs. However, in-group relationships among therizinosaurs are poorly constrained and the purported monophyletic relationship between Therizinosauria [sic] and Oviraptorosauria, although a widespread hypothesis, has received little testing in a comprehensive phylogenetic framework. The recent discovery of the most primitive and most complete therizinosaur known -- *Falcarius utahensis*, from the Barremian of Utah -- offered the opportunity to reevaluate our current understanding of this intriguing group of theropods in light of novel anatomical information. A comprehensive phylogenetic analysis of 14 therizinosaurs, 62 outgroup taxa, and 345 characters was conducted to test previously proposed hypotheses on the evolution of therizinosaurs. Results of this analysis support Therizinosauria as sister taxon to all other maniraptoran lineages, and do not indicate a monophyletic grouping with oviraptorosaurs. The unusually high degree of convergence between these groups underscores the critical role of primitive taxa in phylogenetic studies of coelurosaurian theropods. Several evolutionary trends evident in basal therizinosaurs and oviraptorosaurs (e.g. marked heterodonty characterized by elongate, incisiform rostral teeth) are indicative of a dietary shift from macrofaunal predation. These features coupled with the alternative dentition of basal ornithomimosaurs and alvarezsaurs suggest that dietary experimentation may have been a primary driver in the rapid diversification of Coelurosauria.
<<


Anyway, in the case of troodontids, if these were non-hypercarnivorous, this was probably secondary given that _Sinovenator_ (the most basal known troodontid) was most like dromaeosaurids in its ecomorphology.

What about *Jinfengopteryx*? And who except Scott knows where this one http://dml.cmnh.org/2005Oct/msg00461.html belongs and what teeth it has...