RE: Built Like a Race Horse, Slow as an Elephant?

[evelyn sobielski <koreke77@yahoo.de>]

> I know sauropods are somewhat scarcer on the ground
> in the late Cretaceous, 
> so what sort of speeds do we have for ceratopsians
> and duckbills?  If the 
> fastest prey species can only run at 10 miles an
> hour, then a 15 mph 
> predator is basically strolling through the buffet
> line of life.

Well

> Come to think of it: have there been any modern-day
> correllation studies 
> between predator speeds and prey speeds?  Could you
> predict anything about 
> one from the other?  Probably not any direct
> deductions, but any positive 
> results would be intriguing.

I think your idea fits for cheetahs, lions, hyenas and
canids. The latter two are long-distance chasers and
are able to keep up a sustained speed marginally
higher than their prey (i.e., not decisively higher).
They are also able to produce higher burst speeds
(canids - less so in hyenas) for the kill, and to
avoid becoming prey themselves as they're not apex
predators. Cheetahs and lions (a little bit less so)
max the burst speed, which is a little bit more than
their prey can muster. As compared to long-distance
chasers, the difference between predator and prey
speed ist higher here though because they do not wear
down their prey before bringing it down.

Other big cats are much more into ambush predation, so
for them it's burst speed, or actually just
acceleration as there is no real chase to speak of
(optimally - if the prey manages to avoid the initial
attack, it's liable to get away).

T. rex makes an unlikely ambush predator at least of
duckbills methinks. One could roughly estimate its
possible power output and thus acceleration, and
although close to pure conjecture, together with the
speed larger duckbills could muster one would be able
to get a good idea how close a T. rex would have to
let a duckbill get to succeed often enough as an
ambush predator to make a living.
It's highly unlikely to decide the question, but it
could point out whether it is a possibility well worth
further study or if it's less than likely. Maybe parts
of this have been done already.

> What would you term such a study?  Ecological
> biomechanics? ;-)

"Definitely a worthwhile approach" in any case.

Eike




        
                
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