[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Velociraptor scavenged azhdarchid pterosaur



Without having read the paper, I'd like to note something:

  Primary consumers at a carcass rarely, if ever, go for the hard, crunchy 
bits. They will process much of the leg meats and some of the choicier innards 
before leaving the carcass for the secondary consumers, who may themselves go 
for the bones if specialists. This is largely true of cats, however, who have 
narrow carnassials and are essentially hypercarnivores, leaving little bone to 
their diet or capability to process. Dogs, on the other hand, including their 
jackal cousins, are great hypocarnivores with broader carnassials and more 
capable jaw muscles for processing bone. So wolves tend to be able to process 
several stages of a carcass, unlike cats. *Velociraptor mongoliensis* (I'm 
assuming the specimen is *mongoliensis*, authors continue their trend of not 
talking about species and opting for "generic" useage instead) has very, very 
slender teeth and are not at all like the broader, more resistant teeth of 
*Dromaeosaurus albertensis*, and I am thinking their diet is very heavily meat 
based, making them unlikely to be secondary or tertiary consumers (scavengers). 
Despite this, bone bits suggest maybe they are consuming already processed bone 
fragments (for nutrition) and/or the specimen accidentally choked on the bones 
while processing fleshier remains (which makes the argument for scavenging apt).

  But again, I haven't read the paper (uncorrected proof, recall -- it can 
still be emended!), so I am not aware of the arguments the authors made.

Cheers,

  Jaime A. Headden
  The Bite Stuff (site v2)
  http://qilong.wordpress.com/

"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 
Backs)


----------------------------------------
> Date: Sat, 3 Mar 2012 19:35:21 -0800
> From: mickey_mortimer111@msn.com
> To: dinosaur@usc.edu
> Subject: RE: Velociraptor scavenged azhdarchid pterosaur
>
>
> But flesh doesn't preserve in the sediments that preserve Velociraptor, so 
> how do we know its stomach wasn't full of tasty pectoralis muscles and such 
> in addition to a wing phalanx?
>
> Mickey Mortimer
>
> ----------------------------------------
> > Subject: Re: Velociraptor scavenged azhdarchid pterosaur
> > From: jeff@jeffhecht.com
> > Date: Sat, 3 Mar 2012 21:35:29 -0500
> > CC: dinosaur@usc.edu
> > To: mickey_mortimer111@msn.com
> >
> > I've read the paper, and the authors argue that if the velociraptor had 
> > brought down such a large prey, it would have eaten flesh rather than bone, 
> > and suggest that little flesh was present by the time the dinosaur got 
> > there.
> >
> > - Jeff Hecht
> > On Mar 3, 2012, at 8:18 PM, Mickey Mortimer wrote:
> >
> > >
> > > Scavenging's certainly possible, but since the closely related 
> > > Deinonychus is generally accepted as predating Tenontosaurus (which is 
> > > about as heavy compared to Deinonychus as Quetzelcoatlus is compared to 
> > > Velociraptor), I don't see how we can favor one hypothesis over another. 
> > > Sure I'm assuming that the Velociraptor was found singly, but if Roach 
> > > and Brinkman (2007) are correct that Deinonychus did not live in packs 
> > > but merely aggregated to kill, then a lone dromaeosaurid with parts of a 
> > > large animal in its belly is just what we'd expect.
> > >
> > > Mickey Mortimer
> > >
> > > ----------------------------------------
> > >> From: MHabib@Chatham.edu
> > >> To: mickey_mortimer111@msn.com
> > >> CC: dinosaur@usc.edu
> > >> Date: Sat, 3 Mar 2012 19:36:28 -0500
> > >> Subject: Re: Velociraptor scavenged azhdarchid pterosaur
> > >>
> > >> It is. I've seen David Hone's presentation on this study a few times 
> > >> now, and it was quite a big azhdarch that the velociraptor was chewing 
> > >> on. Highly unlikely it predated something like that.
> > >>
> > >> --Mike H
> > >>
> > >> Sent from my iPhone
> > >>
> > >> On Mar 3, 2012, at 7:15 PM, "Mickey Mortimer" 
> > >> <mickey_mortimer111@msn.com> wrote:
> > >>
> > >>>
> > >>> Hopefully the evidence the azdarchid was scavenged is better than the 
> > >>> evidence the enantiornithine Microraptor ate (O'Connor et al., 2011) 
> > >>> was predated.
> > >>>
> > >>> Mickey Mortimer
> > >>>
> > >>> ----------------------------------------
> > >>>> Date: Sat, 3 Mar 2012 12:03:05 -0800
> > >>>> From: bcreisler@gmail.com
> > >>>> To: dinosaur@usc.edu
> > >>>> Subject: Velociraptor scavenged azhdarchid pterosaur
> > >>>>
> > >>>> From: Ben Creisler
> > >>>> bcreisler@gmail.com
> > >>>>
> > >>>> A new online paper:
> > >>>>
> > >>>> David Hone, Takanobu Tsuihiji, Mahito Watabe, Khishigjaw Tsogtbaatr 
> > >>>> (2012)
> > >>>> Pterosaurs as a food source for small dromaeosaurs.
> > >>>> Palaeogeography, Palaeoclimatology, Palaeoecology (advance online 
> > >>>> publication)
> > >>>> http://dx.doi.org/10.1016/j.palaeo.2012.02.021
> > >>>> http://www.sciencedirect.com/science/article/pii/S0031018212000946?v=s5
> > >>>>
> > >>>> Stomach contents preserved in fossil specimens provide direct evidence
> > >>>> for the diet of extinct animals. Such exceptional fossils remain rare
> > >>>> for predatory non-avian dinosaurs and each can add significantly to
> > >>>> our understanding of trophic interactions between various taxa. Here
> > >>>> we present evidence for the dromaeosaurid theropod Velociraptor
> > >>>> scavenging on the carcass of an azhdarchid pterosaur, with a long bone
> > >>>> of the pterosaur being found as gut contents of the dinosaur. Despite
> > >>>> previous inferences of dromaeosaurs as hyper-predators, scavenging
> > >>>> appears to have been an important part of their ecology.
> > >>>
> > >
> > >
> >
> >
>