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RE: Ceratonykus braincase described

  It is also a useful explanation for alvarezsaurs developing an opisthopubic 
pelvis, as it allows an expanded gut without invoking closer avian ties than 
_Maniraptora_. One should also note, however, that unlike virtually _all_ 
myrmecophages, alvarezsaurs have a substantive array of teeth, and instead of 
just neat little, crushing teeth, these are tiny little razor-blade teeth. 
Consider the functional anatomy of the jaws and dentition for a second here 
instead of the forearms.


Jaime A. Headden
The Bite Stuff (site v2)

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 

> Date: Fri, 29 Apr 2011 12:41:12 +0200
> From: david.marjanovic@gmx.at
> To: dinosaur@usc.edu
> Subject: Re: Ceratonykus braincase described
> > Extant myrmecophages are not cursorial, because the energy derived
> > from a myrmecophagous diet does not permit high metabolic rates in
> > mammals higher than 1 kg mass (McNab, 1984; J. Zool. Lond. 203:
> > 485-510). Termites have higher calorific value than ants, but still
> > not great.
> Oh.
> That could explain why parvicursorines are so unusually small... but
> they're not _that_ small, are they? And *Patagonykus*, of course, had a
> decent size. Too bad its skull is unknown; but it didn't have as extreme
> forelimbs as the parvicursorines.
> > For _Patagopteryx_ read _Patagonykus_...
>  Yes, thank you.
> Thanks also for posting the reference to Senter (2005). That's what I
> had in mind.
> > If alvarezsaurs were myrmecophagous, I doubt that ants and termites
> > were their ONLY source of food - for the reasons given above. They
> > may in fact have been a relatively minor component of alvarezsaur
> > dietary habits.
> Didn't this thread start as a discussion of the function of the
> forelimbs? :-) That they were used to break termite nests open doesn't
> mean the animal ate nothing else. Though the tiny teeth may constrain
> the options for what else they ate.