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Re: T. REX THE HUNTER(finding cover) LONG



Okay, let's backtrack a bit.

The reason the "finding cover for a 5 ton carcass" hypothesis was put
forward in the first place was to explain the (tyrannosaurid) bite
impressions found on the face (skull) of a specimen of _Triceratops_, the
idea being that the tooth impressions may have been caused by a tyrannosaur
clamping onto the face of the ceratopian and dragging the carcass to a
location where the body could be consumed in peace.  I see several problems
with this scenario.  I'm not saying it couldn't have happened, but I think
that the likelihood is low and that other, more plausible explanations
should be considered before wholeheartedly embracing the proffered
hypothesis.

In support of the "finding cover" hypothesis, it has been noted that a
human can easily hide in the modern forest from another human (or from a
dog, for that matter), and the suggestion that a tyrannosaur would have
difficulty hiding a ceratopian from fellow tyrannosaurs merely reflects the
human bias of a small hominid (such as moi) who would think that because
something is big (relative to humans), it should be hard to hide.  No, the
problem is not how small I am compared to a 5 ton _Triceratops_ carcass,
but what effort it would take to drag such a bulk to a suitable cache, and
just where could you hide such a thing?  And would the efforts be
adequately rewarded so that such labor would be warranted?

Consider some of the problems.  Starting with the obvious, that body is
big.  If the terrain is hilly and densely overgrown, dragging the carcass
through the forest would be just about impossible.  If the region is not
densely forested, how could one find adequate cover for this huge animal,
with its massive head and conspicuous horns?  Even supposing that the
ceratopian were killed in the open (a hunting strategy that would have
given the intended prey fair advance warning of impending attack), the
inert body of the slain animal would presumably have to be dragged across
the terrain into a forest to a proper "hiding place."  If the cache is to
conceal the body adequately, then how could the tyrannosaur drag the
ceratopian into the selected spot without knocking down the very cover
required for concealment?  If the theropod were to (somehow) knock down
trees or tear off enough vegetation to cover a five ton ceratopid, this
would make a lot of noise.  Wouldn't the large scale dragging effort and
activity likewise create a lot of disturbance in the forest, alerting
meat-eaters of every size to what was going on?  I would expect that the
noise and plowing action of this carcass-dragging activity would cause all
kinds of smaller animals to scatter and make warning cries to their kind
for the duration of the hypothetical dragging.

If the tyrannosaur intends, instead, to drag the body across more open
ground to a convenient pit or "lair" (rather than plowing through a forest
with such an ungainly load), then it had better have a cavernous pit or
lair in very close proximity to the kill site (or death site, in the case
of the ceratopian dying of natural causes), or the effort required to drag
the dead weight for a long distance would be too much, even for the
powerfully muscled _Tyrannosaurus rex_.  And, of course, if the task is
accomplished out in the open, then it will be observed by all animals in
the vicinity.  Moreover, either one of these labors would not only be
tiring for the theropod, but would put it in a most vulnerable position for
as long as it takes to accomplish. 

Even if no alarm is sounded by startled animals nearby, consider what would
happen when the feast begins.  Not only must the ceratopian remain hidden,
but the gorging theropod as well.  Consider the feeding style of the
tyrannosaur, with its massively muscled spike-studded jaws, crunching
through bones to dismember the body, tearing off shovel loads of meat and
bolting them down its capacious throat, and spilling open reeking,
bacteria-rich viscera.  The smell of blood, the sound of bone-crushing
bites, the stench of the guts.  I cannot see how the meal could possibly be
consumed without attracting a lot of attention!  And I can see no reason
why the tyrannosaur should hide the food away for later consumption when it
would be so much easier and more efficient to eat it on the spot.

The tyrannosaur has big jaws, strong neck muscles, and a big gut, perfect
for consuming large meals.  The tyrannosaur would probably eat as much as
possible as quickly as possible, and perhaps nothing else on earth has ever
been so well-adapted to do just that.  It is also well-armed to defend
itself against others that might try to steal the food from under its nose.
 But if the meal is a five ton ceratopid, this quantity of food could be
too much for a single tyrannosaur to consume in one sitting, although a
family group would presumably be able to eat the bulk of it.  The biggest
threat would appear to be other tyrannosaurs which could fight over the
carcass, chase off the original tyrannosaur, and claim the spoils.  Small,
stealthy animals might scurry or fly in for a nip while the tyrannosaur was
feeding, but medium-size carrion-eaters might keep their distance until the
tyrannosaur has had its fill.

Even if a solitary tyrannosaur had filled its belly without being seen,
heard, or smelled by other animals, it would probably be unable to hide the
remaining portions of the smelly carcass from the denizens of the primeval
forest for long.  And, having just made a kill, "dragged the carcass to a
place of concealment,"  and feasted, it would have become exhausted, and
its full belly would take some time to digest its enormous meal, so the
tyrannosaur would have no longer posed much threat to competing scavengers.
 (If one accepts the hypothesis that tyrannosaurs were gregarious animals,
one may consider the possibility that families or groups of tyrannosaurs
would ward off competitors, allowing the large theropods to eat the carcass
over a longer period of time, although this would not preclude possible
disputes between unrelated tyrannosaur groups).  Like the lions of today,
the tyrannosaurs probably needed to rest after a full meal.  During this
window of opportunity, scavengers would locate the carrion and feast.  They
would probably not care whether the remains had been well-hidden or not;
they _would_ find the meat.  That's their job, and they have adaptations
which enable them to do it with some efficiency.

In short, I fail to see the "ease" with which the tyrannosaur could conceal
a dead _Triceratops_ individual, and I don't see the advantage of this
expenditure of energy, because it would appear to me that the body would be
found promptly enough anyway, and -- as is the case with the hyena of today
-- the theropod would be quite capable of defending the bulk of its food
while it was eating without the need to hide it.  While competing
tyrannosaurs could threaten this strategy, the very act of dragging the
five ton body through the forest (or for some distance in the open) to a
suitable place of concealment would threaten to so exhaust the victorious
tyrannosaur as to render it incapable of defending its meal.  And, besides,
if the idea is to hide the meal from other tyrannosaurs, there is the
problem that _Tyrannosaurus rex_ is renowned for its olfactory sense, so no
amount of visual concealment would do the job.

The proffered analogy that modern humans have taken a long time to find
ancient ruins in Cambodia is not especially apt; the crumbling stone
temples in question were covered with many, many years of jungle growth and
we humans have evolved no biological adaptations for smelling or otherwise
readily detecting concealed structures of archaeological significance.

Now, I suppose it's my prerogative to offer a hypothetical rationale for a
_Tyrannosaurus rex_ frontally biting a _Triceratops_ on the face.  First, I
recognize that any answer here is, at best, a guess on my part, and that I
am not particularly qualified to respond.  Okay, now on to wild
speculation...

Suppose that the tyrannosaur were pursuing the ceratopian, and, in a
conventional defensive behavior, the well-armed ceratopian saw the theropod
coming and turned to face the attacker, lunging forward with its horns. 
What, then, might the tyrannosaur do to avoid being gored by the horns?  I
would speculate that the tyrannosaur might bite into the face of the
ceratopian, and bite down hard (with the capability of delivering more
force than the weight of a pickup truck with each of its robust,
bone-crushing teeth).  In this way, the tyrannosaur could hold off the
horns and beak, and also, perhaps, give the ceratopian such a jolt that,
upon the release of its head, the quadruped would turn tail and try to
escape, or at least back off.  This would give the tyrannosaur an
opportunity to back away from the ceratopian's business end.  It would also
give the theropod an opening to either launch another assault or retreat
and try to find easier prey.

So you see, the face-biting incident suggested by the _Triceratops_ skull
may, in fact, reflect a principally defensive -- as opposed to offensive --
strike.  I suspect that a tyrannosaur would prefer to bite a ceratopian
anywhere _but_ on the head, but on the other hand, I would think that the
tyrannosaur might well use its teeth on the ceratopian's face in a
desperate effort to defend itself against being gored.  I do not know how
plausible my scenario is, or whether it is consistent with the bite marks
in question, but I offer it as an alternative to the "finding cover"
hypothesis.

Ralph Miller III <gbabcock@best.com>

"Bring me a shrubbery."