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Re: The absurdity, the absurdity (long)(was: Cooperating theropods?)
Chris Campbell wrote:
> Larry Dunn wrote:
> > > Sankarah wrote:
> >
> > >The Tugrugeen fossil shows a Velociraptor who seriously miscalculated.
> > >There's no way that could be the norm, because that fella was doomed
> > >from the get-go.
>> We have a preserved dromaeosaur in the midst of a prey event which
>> neatly explains the use of the sickle claw.
> A dinosaur getting chewed on by its prey! Yeah, it's a good use, if you
> don't get your throat ripped out by your intractable victim.
We have no proof that this was a 'prey event' at all. Yes, there is
obvious signs of conflict but with ALL the evidence present, this could
as easily be one animal objecting to the presence of the other animal
within it's territory (especially if the sand-dune-collapsing phenomena
had spooked either of them) and fighting as one eating the other and
fighting.
What leads you to be so positive that one was attempting to kill the
other to eat it?
>> On the other hand, we have a hypothesis of hunting based on no solid
>> evidence other than the size of the claw (a claw apparently demonstrated
>> in use per above), and which requires a great deal of optimism and
>> speculation.
> Don't forget the most important point: lots and lots of Deinonychus
> teeth and remains associated with Tenontosaurus skeletons.
Sure. I can come up with one, no two, scenerios that can explain this
and neither uses the Deinonychus hunting animals larger than itself.
1) The Tenontosaurus skeletons show that there was probably a herd
present. A group of Tentonosaurs. The herd probably had juveniles
ranging from 2 feet long up to near-adult sizes (that would allow for
flank speed in travelling with the adults in the herd). If teh
juveniles of Tenontosaurs were as numerous as the clutches at Egg
Mountain might have us beleive, that would be a lot of babies, toddlers,
pre-teens, and teens hanging around amongst the adults. Deinonychus ate
the smaller juveniles. And ALL dinosaurs loose plenty of
teeth-remember?
2) Tetonosaurus herd/group again. Lots and lots of them. Lots of
poop. Dung beetles live in the poop. Little furry animals eat the dung
beetles. Deinonychus eats the mammals that eat the dung beetles. And
ALL dinosaurs loose plenty of teeth.
>> Why do you prefer the second hypothesis?
> Because the former showed the predator getting his butt kicked by his
> victim? Because the arguments advanced by Ostrom and others are
> sensible and believable? Because of the tight association of predator
> and prey remains? Take your pick.
my explanations are both as likely. It's all SPECULATION.
> > > That claw would be overkill on just about anything under a
> > >quarter ton; you can *bite* anything smaller to death with no
> > >problem, as shown by the innumerable other small therapods running
> > >around.
>> You're presumably not proposing that the velociraptor could kill that
>> protoceratops with it's jaws.
> Uh, why not? If a tiger can kill an elephant all by its lonesome, a
> Velociraptor should be able to take out a Protoceratops.
And ferrets prey on humans. No, really I saw a news clip on CNN about
two pets that mauled a baby.
This is now the kids' arguement 'who would win in a fight?' and simply
because a dinosaur is plausibly capable of taking out another dinosaur
is NOT proof that they regularily did so.
>>Why not quickly slit the belly of a lizard or mammal before popping
>>it in your mouth?
> Why not just bite its head off and be done with it? Why invest in a big
> ol' claw if you can pick up the lizard anyway? It's a waste of time and
> effort.
In general, from stomach contents of dinosaurs eating things smaller
than their heads, they swallowed the whole animal.
The claw may simply be the 'antlers' of dromasaurids-just something to
make them look more-babelike to each other. And might just be used
against their own kind. Like the spurs on a rooster.
>> Sure, small dinosaurs and other smaller life forms got their share, but
>> that doesn't exclude dromaeosaurs in any way from a share (just as a
>> variety of animals feed on mice today).
> Yeah, but big animals go for bigger food. Why? Because they can, and
> because competing with snakes isn't worth the trouble (unless desperate,
> a la wolves in summer).
Wolves and coyotes eat a lot of rodents and rabbits. Enough to effect
rodent and rabbit populations near farmers.
(enough that where there are NO large predators there are LOTS and LOTS
of rabbits, like Australia)
So do bobcats, and lynx. Cougars seem more bird-y (except in California
where they seem to prefer joggers- j/k).
Mouse is one of the earliest kills made by juveniles on their own.
Bears eat a lot of fish when it's available. Lions eat porcupines a
lot.
I think you've exaggerated the ratio of large predator to large vs small
prey.
>> We have to get them all together without mutual antagonism (which, the
>> evidence suggests, their brains seems to have been incapable of),
> Incapable of mutual antagonism? I don't think so. Irregardless, you
> don't need to be bright to tolerate others. Birds, fish, ants,
> antelope, anything you care to think of; intelligence and tolerance are
> not necessarily related.
Why don't you think so? Have you evidence that dromosaurs were bright
OR tolerant?
Tyrannosaurs ARE the only predatory dinsoaurs so far PROVEN to be social
(or anti-social) with their own kind yet, after all.
>>and hungry at the same time.
> Uh, coordination? Daily cycles? Synchronization is ridiculously
> simple.
You left out location-your Deinonychii are all milling around the same
area, which is around the milling-around Tetonosaurs
>> We have to get them to select the same animal, particulalry difficult in
>> the case of herd prey.
> Not really. One takes the lead and the others go with. Whoever goes
> first selects the prey, and occasionally (or maybe often) things go
> FUBAR because they trip one another up. As long as they're fed, it
> doesn't matter how much they screw up.
Natural Selection favors you IF you survive to pass on your genes. I
think predators are a tad more careful about their well-being than this.
> You're trying to make it excessively complicated. If you broke a lion
> strategy down like this you'd wind up with ten times as many steps (who
> does the killing bite? Who chases? Who ambushes? Who harasses? It'd
> get really messy really fast).
Keeping track of which alpha lioness did what or whether a daughter was
allowed to do something by her mother is a full-time job among lion
behaviorists. It DOES get messy in a social species who gets to do what
to whom. Does anyone have some modern reading on lion behavioral studies
to recommend?
> > >But that aside, I seem to recall hearing that they might not have been
> > >as dumb as previously assumed. Studies in birds today show that
<snip>
>> Even assuming that's true, the smartest theropods weren't much smarter
>> than the dumbest birds. And even the smartest birds do not generally
>> show much cooperation in feeding.
> Uh, that may be because they're HERBIVORES! Or, at most, insectivores.
> Most birds are not carnivorous! Talk about apples and oranges . . .
What or who you eat does not effect how bright you are. Chimps are
generally cooperative omniverous scavengers.
<snip>
> And note that (as nicely illustrated by the painting) they wouldn't need
> a wide range of movement and wouldn't need to grasp at all for this to
> work. They hook their claws (nicely curved, note) over a dorsal ridge
> and hang on for a kick or two, then fall off and repeat.
That dorsal ridge is how high off the ground? You have what proof that
dromosaurids regularily leapt higher than their own head?
<snip>
> > >T. had nothing whatsoever. No bite to speak of, no weaponry, not
> > >even any hooves. Not even mass. That sucker *was* meat on the table.
>> Until they crush your hindlimb or break some of your ribs or break your
>> jaw or one of your forelimbs.
> HOW?!? No hooves, no horns, no tusks, no trunk, no flexible tail, no
> bite, nothing to crush with!
It could just step on your foot. Theropod bones are hollow, remember?
<snip>
> Tenontosaurs didn't have
> hooves, couldn't kick with their rear limbs, and couldn't do much with
> the forelimbs. Also note that if they could do anything with the
> forelimbs, your jugular idea is right out, since anyone attacking from
> the front would be swatted down a lot more easily than someone from the
> flanks.
T had roughly the same leg structure as the D's you have jumping all
over him. If D's can do Rockette-kicks, T's could do a nice drop kick.
And D's have hollow bones like birds and T's are built solid like a
buffalo.
>>I'm sure you're not suggesting that predaors are generally reckless.
> Of course not. I'm suggesting that they're not fragile little birds who
> can't take a little punishment. They seek to minimize injury, but they
> can take some rough handling because that's what they do. Prey animals
> don't succumb easily most of the time; they get rolled on, trampled,
> tossed, butted, kicked, and a variety of other things every time they go
> out. They can hack it, make no mistake.
They aren't 'fragile little birds'? But birds ARE dinosaurs-if a bird
aint built to take a little punishment then perhaps you might think
about that for a second. Go ahead.
> > >mammals use lures, stealthy approaches, ambushes, decoys, precision
> > >wounding, specific patterns of movement, and on again off again shifts
> > >in their attacks. Unless you exclude all dogs, social cats, and hyenas
> > >from "most *mammalian* predators" the scenario I describe doesn't even
> > >come close to being coordinated. If you do exclude those animals,
> > >what's left isn't social enough to count.
>> Yes, different species of pack-hunting mammals each use *some* of these.
> Lions and dogs use most of them, if not all. The deinonychus in my
> scenario would use none.
no precision wounding? They don't eat much then.
> > Lures (one animal drawing the attention of the tenontosaur while another
> > hops on from the other side),
> No, there are no lures in my scenario. They just jump on the side
> without the head. There is zero need for coordination here.
In killing another animal, the head is the most usual target to watch
out for. It yells for help, for one thing. It bites for another. It's
the end that breathes for a third.
>>specific patterns of movement and on-again, off-again shifts (attacking on
>>both flanks; in waves)
> No. No waves, just random attacks. No on-again, off-again movement (by
> which I meant taking shifts for pursuing animals, as evidenced by hyenas
> and African hunting dogs).
This is terribly energy inefficient, besides being ineffective. I don't
think even being warm-blooded will help the shear fatigue this type of
combat will leave.
> That's the only one that makes sense to me, actually; how would the
> Tenontosaurus kill them, anyway? Nibble them to death?
Try kicking a head in, smacking a tail across a nose (crushing all those
hollow bones in the face) or rolling on a dromosaur. Having a horse
roll on a person (who is not as hollow-boned as a Deinonychus) will
break the person. T's are bigger and heavier than horses.
Defenseless? I think not. ;]
<snip>
> Larry, stick to the message at hand. Criticizing mannerisms and/or
> grammar is much poorer etiquette than using "uh" in the first place.
Or "look really stupid". Everybody should be more polite or I'll sic
Mickey on the whole bunch of you.
> > > they were grabbed by the myriad other small predators running
> > >around. Particularly the really fast ones.
>> They were? And smaller dinosaurs were likewise grabbed? Monitor
>> lizards? Wolves regularly take smaller animals as well as large ones,
>> and wolves are real pack hunters.
> And lions don't, and they're real pack hunters. Your point? Wolves
> also don't have much in the way of competition (which is why they do so
> well in the U. S. and Canada;
bobcats, lynxes, cougars, bears, coyotes all compete with wolves.
Perhaps not on the islands that have been previosuly mentioned but they
do in Yosemite and in other West Coast parks. (I would think wolverines
up north might be added to the list)
> in Asia they're bullied incessantly by
> wild dogs); coyotes, foxes, and sometimes bobcats/lynxes. Small prey is
> abundant in NA at the moment, but that would likely not be the case with
> a variety of species running around (as is the case in Africa, where the
> social predators don't go for smaller prey nearly as much as their North
> American bretheren).
The small vertebrate animal niches are not missing in Africa at all.
There is a diversiy of smaller mammals, just as there are in Europe or
N. A. Why would you think that this would change due to the size or
variety of predators? It's just a niche which is part of a larger group
of animals.
<snip>
> > >What is it that you have against a precocial pack predator?
>> I have this thing against wild speculation employing a legion of
>> mutually dependent, rather forced rationales.
> Forced? I don't see how jumping onto a hadrosaur and stabbing it is
> forced. You're making the concept much more elaborate than it needs to
> be so I can see why you might think that, but if you look at what I'm
> suggesting it's fairly simple. Certainly simpler than making a strategy
> of attacking prey animals head on in an effort to get your claw into
> their jugular.
It's all SPECULATION. That's forced to fit the facts, such as they
are.
-Betty