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RE: Do we have dromaeosaurid evolution backward?
Not to contradict you here ;) , but Zanno and Makovicky actually left
Ornitholestes unassigned, as they said its diet was inconclusive. The only
"herbivorous" characters it is coded as having are-
1. Decurved dentary. Not obviously true in the left mandible, this is also
found in Masiakasaurus, Coelurus and many (probably insectiviorous or
piscivorous) Mesozoic birds.
2. Ischium longer than 66% pubic length. This is the basic arrangement for
theropods... er... archosaurs... er amniotes. So this is present in
carnosaurs, tyrannosauroids, megalosauroids, ceratosaurs, etc.. Not a
herbivory-related character at all.
Given the fairly large, recurved teeth and generally
carnosaurian-tyrannosauroid nature of the taxon, I would doubt if Ornitholestes
had more plants in its diet than modern coyotes and such.
The "rather weak cursorial abilities" are based on a tibia which seemingly
doesn't exist. I'd like to know what happened to whatever bone Osborn
identified as a tibia.
> Date: Fri, 19 Aug 2011 16:04:28 +1000
> From: firstname.lastname@example.org
> To: email@example.com
> Subject: Re: Do we have dromaeosaurid evolution backward?
> On Thu, Aug 18, 2011 at 7:53 PM, Renato Santos <firstname.lastname@example.org> wrote:
> > Not that I haven't entertained the notion of Ornitholestes as a basal
> > dromaeosaur(id) ever since I noticed it had the incipient sickle claw.
> Not to contradict you here, but although _Ornitholestes_ has
> traditionally been regarded as a predator (including the day it was
> named), Zanno & Makovicky (2010) found that _Ornitholestes_'s
> characters did not correlate with a hypercarnivorous diet. Instead,
> _Ornitholestes_ was interpreted by this study as a possible herbivore
> or omnivore. Add to that the rather weak cursorial abilities of
> _Ornitholestes_ (especially compared to similar-sized coelurosaurs
> like _Coelurus_), and you have a "traditional form" that was arguably
> more similar to _Falcarius_ in its habits than to dromaeosaurids.