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Re: Dromaeosaur hunting technique (was BCF ET CETERA)
If I had more time I would have written something real similar to this
like you said it is only speculation but I think it is real possible
that this may have been the case.
>There are surely a variety of possible dromaeosaur hunting scenarios,
>depending somewhat on the size, speed, and body type of the prey item
>question, and whether stealth, endurance pursuit, or pack hunting
>into your view. In our mammal-dominated world, big cats may finish off
>their quarry with a precise bite, but the initial strike is often more
>matter of batting with the paws, snagging or hooking with the claws,
>requiring only so much force as is needed to knock a running animal
>or to drag a standing animal to the ground. While the claws of
>dromaeosaurids bear close comparison with those of cats, the remaining
>anatomy is so unique as to defy easy analogies with extant fauna.
>weary of reading unprovable hypothetical behavioral scenarios are
>to skip the following.
>Imagine, if you will, a _Deinonychus_ pack leaping onto a
>individual with all claws at once (each theropod pulling its neck back
>an s-curve during the initial strike). Perhaps the dromaeosaurs would
>quickly jockey for position until each secured a firm grasp of the
>ornithopod with their forearms, freeing up the legs to facilitate
>the ornithopod to ribbons.
>Catching a relatively small animal might entail a powerful raking or a
>knockdown kick with the powerful feet (think cassowary or kangaroo),
>followed by firmly gripping the grounded prey with the hands, and of
>course, the obligatory raking with the claws of the feet.
>Dromaeosaur arm dynamics, though in some respects more restricted than
>mobile articulations of their mammalian carnivore counterparts, should
>necessarily preclude snagging capability. Even if a dromaeosaur were
>contact the prey with only one hand, this might be adequate, for the
>cheetah can knock a running gazelle off balance by hooking it with a
>claw. (And the cheetah's dew claws, like the hypothetically raised
>dromaeosaur killing claws, are held off the ground at all times, and
>maintain their sharp hook, because there is no contact with the ground
>dull them). Once the prey falls, the theropod could use its arms to
>into its prey, securing the animal while administering lethal kicks and
>In any case, even if the dromaeosaurid arm anatomy didn't enable rapid
>grasping of prey, the articulation would appear to be useful in firmly
>holding onto the prey -- "palms"-in --against the force of the kicking
>legs. The semilunate carpals could even enable a dromaeosaur to tuck
>phalanges posteriorly (in the manner of a bird folding its wings) in
>_diametric opposition_ to the force of the kicking feet. With such a
>configuration, this swinging of the wrist might occur inevitably (and
>fortuitously for the predator in this case). Were the dromaeosaur to
>the struggling prey with the hands in the "palms"-forward position, its
>kicking feet could actually push the prey animal out of its hands, away
>from the predator, facilitating escape! The "palms"-in articulation is
>utilized by small cats holding onto their prey (or their feline rivals)
>while raking with the hind claws. The dromaeosaurid ability to tuck
>hands back against the forearm could represent a further (albeit
>refinement of the technique.
>Hence, one could argue that natural selection might favor adaptations
>enable a "clapping" grasp or posteriorly directed hands in
>even if such adaptations are not specifically used in "snatching" prey.
>Opponents of this view would argue that the articulations of the
>arm, and wrist are more plausibly associated with flapping flight, and
>have been present in primitive birds ancestral to the dromaeosaurs. In
>that case, the described hunting scenarios may still have occurred, but
>suggested behaviors would not have provided the driving force behind
>> Now, instead of grabbing a prey animal, suppose that instead, it was
>> onto a tree trunk?
>I wouldn't rule out that possibility, either, especially with those
>jackboots of theirs. I would have appreciated more thoughtful
>consideration of arboreal theropods in the _Scientific American_
>but it is not my place to tell others what to think or say. I provide
>foregoing to suggest some of the many ways in which the dromaeosaur
>forelimb anatomy could have possibly been beneficial in subduing prey
>from the problematical "power-clap in prey grabbing" technique you
> That dromaeosaurs used their forearms in some way is not
>but just how they used them is the question. In some matters, one can
>speculate, and prepare for the inevitable flames.
>Ralph Miller III <email@example.com>
>"It's in the wrist action."
"Quit Honking, I'm Reloading"
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