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

Re: Planet Dinosaur Ep 2



Richard W. Travsky <rtravsky@uwyo.edu> wrote:

> Would that not put a lot of stress on the claws and foot (and leg)? All
> that thrashing while "connected"?


It's my impression that this "connected-ness" with the prey would have
reduced the amount of stress on the hindlimb, including the claw.  The
predator was locked in place, with all four limbs used to embrace the
predator.


It's also worth noting that under this hypothesis, the pes was
specialized for gripping large prey, not inflicting trauma in its own
right.  Manning et al. (2005) actually argue that no slashing or
cutting occurred, once the claw was embedded in the flesh.  This is a
shift in the way the dromaeosaur sickle-claw has traditionally been
viewed, when employed against large prey (i.e., as an instrument for
evisceration).  Against smaller prey, such a deep wound would be
traumatic, and struggling would only make it worse.



Dann Pigdon <dannj@alphalink.com.au> wrote:


> This may suggest that velociraptorine unguals would have been better suited 
> to the sort of hit-and-
> run predatory tactics seem in poisonous snakes or great white sharks. A 
> series of quick plunging
> attacks with the foot claws followed by a rapid retreat to evaluate the 
> situation. Eventually the prey
> might have succombed to either shock or blood loss from the repreated 
> strikes, with a minimum of
> risk to the dromaeosaur in question. This is pretty much the tactic employed 
> by secretary birds
> against snakes.


All this suggests that the second pedal claw of dromaeosaurs was used
to slash through flesh - which is what Manning et al. (2005) endeavor
to refute.  But the hit-and-run tactics might have worked against
smaller prey, for which a deep penetrating wound would be potential
fatal.





Cheers

Tim