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Re: Velociraptor scavenged azhdarchid pterosaur
----- Original Message -----
From: Dan Chure <email@example.com>
>I agree with you that the superpredator model is too widely and wildly
applied. However, the issue still is can the V-P predator event
hypothesis be tested? If so, how and is there evidence to test it?
Photos of the fightn' Veloc-Proto (including closeups):
I think that the fact that the Velociraptor arm seems to be in the
Protoceratops mouth may be taken as reasonable evidence that both belligerents
were alive at the time. the fact that they both died might indicate that
something went wrong. Whether or not the Velociraptor purposefully attacked the
large Proto, or whether their coming together was accidental is not knowable.
Evidence of active predation (or at least attacks) would be if a predator's
tooth tip was found embedded in a prey's bone, but that the bone showed signs
of healing/response (it could still kill the prey, it just had time to cause
observable response in the bone). Any other evidence is more problematic.
Bite-shaped gaps in neural spines may form in a number of ways, so I am
unconvinced by the tail pathologies of the Denver Edmontosaurus (for example).
Carcass processing occurs whether or not you killed your food or just came
across a carcass. Shed teeth, toothmarks, gut contents, and (sometimes) the
pattern of carcass dismemberment, are all results of carcass processing and are
difficult to use to infer scavenging. I understand the Hone et al argument that
the Velociraptor would not preferentially eat bone if flesh was available...
I'm fairly skeptical, but it is acceptable. It's just worth noting that maybe
the carnivore was unable to more precisely dismember the carcass, and so some
bone ingestion is inevitable. Tough to test.
On 3/4/2012 9:58 AM, Habib, Michael wrote:
> On Mar 4, 2012, at 9:47 AM,
is possible, I don't see how it can be
>> invoked if there wasn't a nest at the site. I understand that there
>> might have been a nest nearby that wasn't preserved but if you have no
>> evidence that there was a nest where the V-P were found it makes no
>> sense to build an interpretation around its being there. The same
>> general region preserving nests is not the same as a nest at the site.
>> There are many Protoceratops found that are not on nests or a nesting
>> sites. So the lack of a nest might be taken as evidence, although maybe
>> weak, that falsifies the nest raiding hypothesis.
> I used to take that same perspective myself, actually. I do agree that nest
> raiding cannot be supported as a specific hypothesis; I was using it more to
> make a point than anything else. Without a nest preserved, I fully admit
> that it is speculation to claim nest raiding, specifically. However, I think
> it still makes the point that there are other scenarios that could lead to
> the combat in question. Why should we consider them? Because the
> circumstances of the fossil should make us immediately skeptical of a
> predation hypothesis. At the very least, we should be extremely skeptical
> that this was a typical or average event.
> Look at this way: if the fossil in question preserved two extant taxa, in a
> similar situation and size ratio, we would be much more confident that the
> predator screwed up, at the very least. For some reason, the strong
> preference bias for small, juvenile prey among even quite powerful modern
> predators doesn't get its due when we examine the terrestrial fossil record.
>> The development of a slicing claw and the attendant morphologies seems
>> to be an odd adaptation if V (and its relatives) regularly fed only on
>> prey smaller than itself.
> Why? Most living terrestrial predators, including animals as powerfully
> armed as cats and birds of prey, hunt animals smaller than themselves. Even
> if the claw as truly a slicing structure (and it might not have been,
> although it's certainly plausib
is relatively large in ecological terms, but still smaller than the predator
(say, for example, 50-66% the size of the dromeosaur).
> I realize that I am going out on a limb a bit - my point is not that my
> speculative hypotheses here are necessarily better, but rather that the
> "super-predator" models so popular in paleontology have not received due
> skepticism. If we can really, truly shore them up then that's great - but it
> should be recognized how extraordinary it would be to have a wide range of
> predators attacking prey much larger than themselves.
> --Mike Habib
> Michael Habib
> Assistant Professor of Biology
> Chatham University
> Woodland Road, Pittsburgh PA 15232
> Buhl Hall, Room 226A
> (443) 280-0181
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