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Re: Qilongia & omnivory



Stephen Pickering (StephanPickering@cs.com) wrote:

<Your logic is, alas, tepid.>

  Aw ... I thought it was at least lukewarm ... but at least we are
working in an interpretive field where observation is not possible in
ecologies, and only assumptions and anatomical comparisons (which say very
little, if anything, about behavior) can be used to infer diet.

<I have seen "carnivores", such as a bear and a mongoose (in Hawaii),
eating bearies and fruit. I have also observed an adult giraffe, with its
18 inch tongue, clean out a nest and eat the chicks and eggs.>

  And there are plenty instances of deer and elephants consuming whole,
adult animals, including the excavating of human graves by the latter. And
there are foxes and bears which are hypocarnivores that typically go after
both fruits and flesh. I am aware of all the exceptions to the rule, and
note that there is no line between carnivory and herbivory, and even
omnivory varies. True carnivores are rare and few and far between ... but
there are distinct osteological and dental correllates that I have data
for that I had hoped to publish on last year, but will have to wait for
some time. The same goes for herbivores, durphages, fructivores, and so
forth. Otherwise, many forms show no distinct emargination of dietary
"variability" that allows them some capacity for omnivory, and on this
note I suggest dietary variability in some fossils.

  Then there's all the dangers of trying to infer extant behavior on
fossils when in fact there is no measure of degree that can be used to
infer anything that does not preserve.

<A crow-sized theropod, in a rainforest or broad-leaved woodland, is not 
going to consult Julia Child for permission to eat any prey it can 
obtain...and it would not surprise me in the least if the feathered taxa
from China were omnivores: berries, insects, lizards.>

  Of course. Troodontids (*Sinovenator*) have been classically considered
insectivorous, and show an extensive palate and micro-teeth that may be
adapted for this [one troodontid, *Saurornithoides mongoliensis*, has very
large lateral teeth and it was probably a more advanced creature capable
of taking mammals, bigger lizards, and so forth], *Microraptor* may be
comparable in it's small teeth and slender snout;
stem-dromaeosaurids(*Sinornithosaurus*) have elongated teeth and recurbed
mandibles and would have easily have taken chuncks from larger prey,
snakes, and equal sized dinosaurs, etc. It's not inconceivable to make
pterosaurs prey for these animals. *Caudipteryx* and *Protarchaeopteryx*
had jaws that seem to be "hooked" in effect, and the non-serrate teeth of
the former suggest piscivory while those of the latter may be uniquely
adapted for something else entirely.

  Beaked forms of course seem adapted for a variety, but a beak does not
mean carnivory, herbivory, or omnivory. It depends on a detailed
examination of all the bones, musculature, bone-compression and
force-distribution analyses, and other functional considerations.

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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