Re: [Giganotosaurus news item]

[archosaur@usa.net]

owner-dinosaur@usc.edu wrote:
> Having read the news item , I'm slightly confused . How could Coniacian
> Giganotosaurus keep Maastrichtian T.rex out of South America
> and vice versa ?Have I missed something ? Additionaly , 
-------------------------------------------------------
Wasn't South America separated from North America at the time anyway.

I'm pretty sure it was in the Coniacian, but I'll have to check the 
Maastrichtian. That's what I figure kept the two giants away from eachother.

-------------------------------------------------------
just when you think the "pack" debate has ended , we have this 'new' evidence
> of "pack behavior " . I attended a lecture on Acrocanthosaurus , given by
> Dr. Dale Russell , Tuesday night . I had the opportunity to pose the "pack"
> question to him. He replied that he thought most theropods were solitary
> predators , occasionally feeding together , like crocodiles sometimes do
> So who knows ?
-------------------------------------

I'm not sure how often crocs paticipate in cooperative huinting, but I do know 
that they are more social than they are given credit
for. There are dominant crocs in  a group and all the other crocs know how to 
give submissive gestures. 

The only time I've seen crocs being truly solitary is on slow flowing rivers 
and in the ocean. This also depends on the animal too.

Alas, I'm straying from the point. Personally I think cooperative hunting in 
Giganotosaur like animals makes sense to a point. 

I could never figure out why theropods never grew to an immense enough size to 
take down sauropods like Argentinosaurus and Seismosaurus. 

Now if they hunted in groups then I could see them taking down a small juvenile 
or sick and old adult Argentinosaur. This I can see.

The only other thing in that article I disagreed with was Rodolfo Coria's 
comparing of Giganotosaurus to Komodo Dragons. He stated that "The animals 
would take a bite of the prey then let it alone to die of blood loss and 
infection." This is only secondary. V.komodoensis's first mode of attack is to 
charge it's prey and tackle it down. With claws that can tear steel and bear 
trap jaws, one can see why most of it's prey falls down the first time. 

The only exception to this would be when the animal is hunting deer. Deer are 
pain to hold on to and when you let them go they run away very fast. So it's 
good to give them the largest and most germ ridden bite possible so that they 
will fall down. That or hunt cooperatively (which they are known to do on 
occasion)

Now Rodolfo Coria's interpretation of a Giganotosaur attack is that of the 
animal charging into the prey, ripping a huge chunk of flesh and letting the 
animal bleed to death or die from infection/shock. 

This is the same hunting strategy of C.carcharius, the Great White, not the 
Komodo dragon.

Other than those few points I had no problem with the article.

Archosaur J


____________________________________________________________________
Get free e-mail and a permanent address at http://www.netaddress.com/?N=1