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RE: Sinocalliopteryx (Theropoda: Compsognathidae) ate confuciusornithids and dromaeosaurids



And so do crocodiles when they lunge into an entire flock of birds gathered 
along river banks.
-d.
----------------------------------------
> Date: Wed, 29 Aug 2012 15:05:30 -0700
> From: mickey_mortimer111@msn.com
> To: dinosaur@usc.edu
> Subject: RE: Sinocalliopteryx (Theropoda: Compsognathidae) ate 
> confuciusornithids and dromaeosaurids
>
>
> But but... surely O'Connor et al. (2011) showed it's most reasonable to 
> conclude associated arboreal birds in a theropod's stomach mean the theropod 
> is probably arboreal. Arboreal Sinocalliopteryx, here we come!
>
> Seriously though, it's good to see a refutation of that silly line of 
> evidence in print. As Xing et al. state-
>
> "O’Connor et al. [54] reported on a specimen of Microraptor
> with the remains of an enantiornithine bird within its abdominal
> cavity, and argued that such presumed predation on a bird with clear
> arboreal perching adaptations was evidence supporting a highly
> arboreal/aerial lifestyle in Microraptor. Based on various
> other lines of evidence, we agree with this ultimate conclusion;
> however, that Jehol birds were evidently on the menu of Sinocalliopteryx must 
> be regarded as a strong contradiction to the necessity of O’Connor et al’s 
> [54] ecological inference. Confuciusornis
> was not as well adapted to perching as enantiornithine birds, but does
> nonetheless possess long curved pedal claws and a posteriorly-facing
> hallux, and was capable of powered flight. While Sinocalliopteryx
> does have proportionately longer arms than most compsognathids and may
> have been capable of tree climbing, it lacks any definitive arboreal
> adaptations; at over two meters in length, is best regarded as a
> predominantly terrestrial animal.
>
> Active hunting
> of flight-capable prey by a land-bound predator may seem intrinsically
> implausible, but there are abundant extant examples, wild felids among
> the most famous. The back-footed cat (Felis nigripes) of southern Africa 
> routinely ambushes and chases down cursorial birds before they are able to 
> become airborne [56]. Servals (Leptailurus serval) are long-legged and adept 
> at pouncing on alighted birds, and at snagging fleeing birds midair 
> [57]–[59]. Avian prey is known to constitute nearly half the diet of some 
> leopard cats (Prionailurus bengalensis) [60],
> which both climb trees to prey on roosting birds and ambush foraging
> birds on the ground. Among canids, foxes are expert bird hunters,
> commonly taking anseriforme, galliforme, and passeriforme game [61], [62]. 
> Among extant reptiles, monitor lizards and various snakes consume birds in 
> both arboreal and terrestrial contexts [63]–[66]."
> Mickey Mortimer
>
> ----------------------------------------
> > Date: Wed, 29 Aug 2012 14:37:37 -0700
> > From: bcreisler@gmail.com
> > To: dinosaur@usc.edu
> > Subject: Sinocalliopteryx (Theropoda: Compsognathidae) ate 
> > confuciusornithids and dromaeosaurids
> >
> > From: Ben Creisler
> > bcreisler@gmail.com
> >
> >
> > New in PLoS ONE:
> >
> >
> > Lida Xing, Phil R. Bell, W. Scott Persons, Shuan Ji, Tetsuto
> > Miyashita, Michael E. Burns, Qiang Ji & Philip J. Currie (2012)
> > Abdominal Contents from Two Large Early Cretaceous Compsognathids
> > (Dinosauria: Theropoda) Demonstrate Feeding on Confuciusornithids and
> > Dromaeosaurids.
> > PLoS ONE 7(8): e44012.
> > doi:10.1371/journal.pone.0044012
> > http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0044012
> >
> > Two skeletons of the large compsognathid Sinocalliopteryx gigas
> > include intact abdominal contents. Both specimens come from the
> > Jianshangou Beds of the lower Yixian Formation (Neocomian), Liaoning,
> > China. The holotype of S. gigas preserves a partial dromaeosaurid leg
> > in the abdominal cavity, here attributed to Sinornithosaurus. A
> > second, newly-discovered specimen preserves the remains of at least
> > two individuals of the primitive avialan, Confuciusornis sanctus, in
> > addition to acid-etched bones from a possible ornithischian. Although
> > it cannot be stated whether such prey items were scavenged or actively
> > hunted, the presence of two Confuciusornis in a grossly similar state
> > of digestion suggests they were consumed in rapid succession. Given
> > the lack of clear arboreal adaptations in Sinocalliopteryx, we suggest
> > it may have been an adept stealth hunter.
>