Re: The absurdity , the absurdity (was:cooperating theropods?)

["Larry Dunn" <larrydunn@hotmail.com>]

From: Chris Campbell <sankarah@ou.edu>

>Larry Dunn wrote:

>> We know that, in all likelyhood, deinonychus was much less 
intelligent
>> than modern pack hunters.  We know that only the most intelligent
>> animals hunt in cooperation with each other.  So what can we safely
>> surmise about the hunting techniques of theropods?
>
>Larry, we don't know any of this.  Modern avian studies show that what
>we thought we knew about intelligence isn't really true at all, which 
in
>turn shows that dinos might (emphasis on the might, here) have been 
much
>more intelligent than their brain mass might indicate.  Though they 
were
>still probably less intelligent than modern mammalian carnivorous pack
>hunters, they may well have had the brains needed to act in social
>groups.  

Well, the common wisdom on "intelligence" can be attacked on even more 
grounds than that.  What we used to see as the "tree of intellect" with 
man at the pinnacle in association with the concept of progress in 
evolution is being torn down by a better understanding of animal 
behavior.  

However the above does not invalidate the rough (Weishampel and 
Fastovsky call it "very crude") but still-useful and still-used 
correlation between proportionate brain mass and intellectual capacity 
in animals.  Paleontologists and other life-scientists readily refer to 
it to this day-- Bakker himself, chief choreographor for the Dancing 
Dinosaurs, did in the 80's (see TDH, p. 369).  

Why do they use it?  Partly because it has proven to be a fair predicter 
of what we observe of animal behavior and partly because we'll never 
*know* how intelligent dinosaurs were.  

Proportionate brain mass, or it's more refined derivate, EQ, is a better 
way to form a hypothesis on dinosaur intelligence than studies the 
results of which suggest that the intellectual ability of a certain 
extant animal is more advanced than EQ would indicate, because we of 
course cannot subject long-extinct dinosaurs to the same studies.  

Who knows, there may have been some trilobite that was a certifiable 
genius at extracting some juicy food source from a protected area with 
pluck and crafty use of certain appendages, but we'll just never know 
that, and it's probably not too terribly inaccurate to predict that 
trilobites weren't the best learners in the fossil record.

I'll continue to respect and refer to EQ as long as Farlow & 
Brett-Surman, Weishampal & Fastovsky, Bakker, et al do so!  It is a 
better frame of reference than nothing at all, and the only reliable 
frame of reference we will ever have on dinosaur intelligence (even if 
"very crude").

(In any event I find those studies of avian intelligence to be 
potentially interesting and would like to learn more.  Could you provide 
a reference?  It'd be very interesting to read, I think, and possibly of 
great relevance to other list discussions.)

>Second, we know flat out that even such simple things as spiders can
>engage in coordinated, pack tactics in an effort to bring down prey;
>this shows quite conclusively that having the smarts of a dog or lion
>isn't necessary for pack coordination.  All that's needed is some means
>of communication (which most animals have) and some means of
>coordination, which would require very simple neural hardware.

Well, as you know, I've argued that we probably shouldn't use 
invertebrate behavior, known flat out or not, as a yardstick in this 
discussion.  When we leave the phylum Chordata comparisons get, pardon 
the expression, really hairy.  The common ancestor to that packhunting 
spider and to Deinonychus lived so long ago that Deinonychus and the 
spider in question may as well be from different planets.

(A second request for a reference: which kind of spider hunts in packs?  
Is there a paper or book you can recommend?  After what's come before I 
guess I should clarify that this is not an attempt to question your 
assertions by challenging you to provide references.)

>None of which says anything about Deinonychus, of course; it may have
>hunted in packs, it may not have.  The statistics say it probably
>didn't, but if any predatory dino is a good candidate it's Deinonychus.

Just as I'm willing to accept the possibility that Tyrannosaurs were 
obligate scavengers, I'm willing to accept the possibility that 
dromaeosaurs hunted larger animals in packs.  Note I've never said that 
it's physically impossible for dromaeosaurs to have hunted in packs.  
Just unlikely.  

The distressing thing about dinosaur science is the way that the 
conjecture about behavior takes on more of a mantle of scientific 
respectability with every reiteration. We've already seen one 
altercation on this list based on some pretty baseless conjecture as to 
the existance of Phobosuchus in a formation far in time and space from 
confirmed Phobosuchus remains; the whole thing started because the 
resident crocodile expert was concerned that this conjecture might 
spread like a wave and eventually appear as "fact" in a soft-science 
book or magazine article. 

This is precisely what has happened to dromaeosaurs generally and to 
Deinonychus specifically.  People accept these hypos as fact and become 
very possessive of them.  They crowd out other hypos, even more likely 
ones.  Note that several of the young people on this list became very 
upset because I was threatening to take away their packhunting raptors.  
 
>> I'm just trying to find the most reasonable interpretation of
>> their lifestyle based on the fossil record and on modern cognates.
>
>Then stick with things not easy contradicted by modern fauna.  Examples
>can be found of modern fauna coordinating their activities with very
>little brain matter, so arguing they're (Deinonychus) not bright enough
>to hunt like this won't work.  

I don't see how this is easily contradicted by modern fauna unless 
you're counting the usual suspects: certain exceptional invertebrates, 
marine life and birds offered as examples. 

>Examples can be found of modern fauna
>taking animals up to ten times their size, so that goes out the window. 

If we once again toss the usual suspects, we're left with some pretty 
uncharacteristic behavior by one or two prides of lions.  I don't think 
we can use this as a gauge of dromaeosaur behavior.  

Even were it not unusual behavior, there's still the probability that 
extant packhunting mammals may be able to behave in ways that the 
dinosaurs simply could not.

>Arguments can be made either way based on physical capabilities.  

Of course, and not just on physical capabilities.  But the arguments 
must be weighed for merit.  We're predicting behavior so we're in pretty 
wooly territory to start.  Isn't it more likely that a valid hypo can be 
formed based on analysis of the dinosaur's own phylum?

>Fact
>is, there's no reason Deinonychus couldn't hunt as a pack predator. 

I'd say that there is. How many animals do we know of today that hunt in 
packs? A small percentage.  There's a good starting point.  When we look 
at a profile of these few, I think that the reason gets even better.
   
>There's no reason to think it did, no evidence whatsoever to support it
>-- but the argument claiming it didn't have the mental and/or physical
>capabilities to do it is false.

All we have to bring to this discussion are the physical and mental 
capabilities of extant vertebrate pack hunters.  That's it.  Otherwise 
we can't discuss this topic at all, unless you also want to discuss 
every other hypo the world could come up with for Deinonychus behavior.  
So how can an argument claiming that Deinonychus didn't have the mental 
and/or physical capabilities to pack hunt be necessarily false?

>It's true that the burden of proof is on those making a case for pack
>hunting, but note that's it's impossible to prove predation of any 
sort,
>by any extinct animal, at any time.  

>The only thing we can do with any
>reliability is determine what seems reasonable in light of the weaponry
>a given animal possessed.  Deinonychus certainly had the weaponry 
needed
>to bring down juvenile Tenontosaurs.  It probably could do quite well
>alone, actually, though if (big if) it hunted in packs is could take
>larger prey.  

I'd also add the animal's intellect into the equation.  Chimpanzees 
certainly don't have an impressive array of teeth and claws, for 
instance, but can still be pretty effective predators.

>> Well, there tends to be a direct correlation between intelligence and
>> relative size of the brain, right?  
>
>No, not right.  If shark studies indicate they might be as bright as
>some birds (and they do) and bird studies indicate they might be as
>bright as some mammals (presumably not the same birds being used, here;
>lots of variety in aves), they the correlation becomes quite suspect. 
>How does one respond to an African Grey Parrot who's a bright as a 
chimp
>and has a brain the size of a grape (maybe plum?).  That correlation
>works within a given group, not between them.  Even within a group it's
>suspect; see dolphins.  The brain can be constructed in various ways,
>and that impacts how intelligent a species may be.

I think that this is pretty clearly the wrong way to approach an 
analysis of dinosaur intelligence, for the reasons given near the top of 
the post.  Showcasing certain studies suggesting the obvious --that EQ 
is unsuited to answer all questions of animal intelligence -- does not 
help us in analyzing dinosaur intelligence, because EQ, flawed though it 
may be, is the only method we'll ever be able to use.  

>>Why make an exception for dromaeosaurs because it would tend to 
discourage 
>>notions of a certain exciting proposed behavior?
>
>See above.  There are dozens of exceptions running around already.  We
>shouldn't condemn on the basis of a generalization.

I don't see taking packhunting off of the top of the list for 
dromaeosaur behavior as a condemnation at all.  And mere dozens of 
exceptions only prove how unlikely these exceptions really are to have 
any relevance.
 
>> I've attempted to base my discussion on fairly commonly known 
dinosaur
>> science and on observation of animal behavior.  
>
>Ammend that to "mammal behavior."  Actually, "common assumptions about
>wolf and lion behavior" might be most accurate.  

I don't think such an amendment would be accurate.  My analysis includes 
all extant vertebrate predators.  This is precisely why I suspect that 
dromaeosaurs were not pack hunters -- because most extant vertebrate 
predators are not.  The fact that mammals come up so often results from 
*your* hypo, because you suggest that dromaeosaurs operated in manners 
most closely analogous to certain extant mammalian predators.

>What you're arguing
>isn't consistent in extant animals; no reason to think it would be in
>dinosaurs.

I'd suggest that if someone with the time and resources looked at extant 
animal species and then determined which proportion of them act 
cooperatively in the manner proposed by you, the resulting percentage 
would be pretty tiny.

>>I don't think I've strayed from that path.  What are the claims of the 
>>pack-hunting enthusiasts based on?  So far, all I've seen is the 
creation of
>>increasingly elaborate scenarios utterly alien to our understanding of
>>animal behavior.
>
>No, they're not.  They might be alien to your understanding of animal
>behavior, but don't generalize your assumptions to include all the
>arachnologists and icthyologists and ornithologists out there who see 
it
>as quite feasible.

I for one haven't polled these workers; do most of them think that 
pack-hunting by dromaeosaurs is quite feasible?  We go in circles on 
this issue.  I leave it to the other readers to determine if the 
behavior of a few discreet species of spiders, fish and birds is 
terribly illustatraive in understanding dromaeosaur behavior.
 
>  There is nothing to support the theory of pack
>hunting in dromaeosaurs -- however, that doesn't mean by any stretch of
>the imagination that it's not possible.  So why bother with it?  
Because
>if any dino did engage in pack hunting, dromies would be it.

Forgive me but this isn't really a valid logical statement.  We could 
likewise announce that if any theropod tried trigonometry it was 
Troodon.

  They're
>the right size (relative to other dinos), 

What is the right size to pack hunt?  Meercats do it, but then again so 
do lions, but then again tigers don't.

>fairly bright (relative to
>other dinos),

Actually fairly dumb (relative to known pack hunting terrestrial 
vertebrates).  Devise a difficult puzzle.  Will the smartest person in 
the room necessarily be able to figure it out?

 and armed in such a manner that they could conceivably
>take prey much larger than they would need alone.

It's conceivable, but it needs to be studied much more carefully before 
we can safely assume anything about it.  Note that there is no consensus 
on the use of the digit II claw -- some think it wasn't used for 
predatory purposes at all.

  This makes pack
>hunting very possible with these animals,

How possible is very possible?  More than 50-50?  I ask because you've 
said above that pack hunting by dromaoesaurs was not probable.  Where do 
you think the probability lies? 

 whereas it's much less so with
>other therapods.

Maybe, African Grey Parrot-like, larger theropods were actually smarter 
than the dromaeosaurs. 

>  This, then, is why I think the notion is so popular. 

I think it's popular because that's all people have been told for the 
past several decades, and because it's dramatic.

Larry



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