Re: late night thoughts: misunderstand what?

[Dann Pigdon <dannj@alphalink.com.au>]

don ohmes wrote:

> "HOWEVER - sauropods are unlikely to have
> coorperated by standing nice and still to allow for such a well-aimed bite.
> I'm not sure how stealthy a multi-tonne tyrannosaur could have been, but I'm
> guessing most saurpods would have known about them long before the predator
> was within striking range..." -- D Pigdon
>
> Aha! So you think *T. rex* (damn, I'm getting to like those little stars; 
> wonder what they are for) capacity for stealth was an issue in relation to 
> sauropods, but not w/ hadrosaurs? What, Are Hadrosaurs stupid, or blind, or 
> something? You dissing hadros?

An adult hadrosaur and an adult sauropod are two very different kettles of 
fish. I'm guessing *most* hadro's were roughly of similar mass (or at least 
less than twice the mass) of a really big tyrannosaur. Whereas a really big 
sauropod (assuming rexes went
for adults) would have been a much heftier target. As a general rule; the more 
mass, the bigger the whallop.

We *know* that tyrannosaurs target hadro's (healed bite marks on the tail). We 
also know that hadro's lacked anything that looks obviously like a means of 
aggressive defense (not even a thumb spike to speak of). Those forelimbs were 
puny, the hindlimbs were
probably too busy trying to skedaddle, the tail was far less mobile than that 
of a sauropod (all those stiffened tendons) and using their (relatively blunt) 
beaks would have meant putting their heads within chomping distance a rex's 
business end.

Also - hadro's could run. That means that a startled hadro could eventually run 
out of puff, or trip and fall in a panic. Either way they'd have presented a 
relatively easy meal. Sauropods couldn't run to save themselves (literally), so 
I'm guessing they used
more of a 'stand and fight' tactic. Did rexes give chase to hadro's? Maybe. 
What sort of evidence might back up such a claim? Something like healed bite 
marks around the tail region perhaps... :)

How many  pre-mortem bite marks have even been found on a large adult sauropod 
fossil?

--
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Dann Pigdon
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://heretichides.soffiles.com
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