Re: Deinocheirus (was Sauropodz r kewl WAS: silly conversation on 2012 US presidential race)

[tyazbeck@comcast.net]

NICE! BTW I am back from surgery that I had on Thurs. I had a catheter removed 
today... :-( but I'm on the road to recovery.

PS.: Where is the type specimen of Deinocheirus currently at?


From: "Tim Williams" <tijawi@gmail.com> 
To: dinosaur@usc.edu 
Sent: Thursday, April 19, 2012 10:04:59 PM 
Subject: Re: Deinocheirus (was Sauropodz r kewl WAS: silly conversation on 2012 
US presidential race) 

Thomas R. Holtz, Jr. <tholtz@umd.edu> wrote: 

> Having held the claws (well, casts) of Deinocheirus, they are bigass, but 
> they aren't really fearsome. Now a Torvosaurus or 
> spinosaurid or megaraptoran claw: THOSE are scary nasty! 


Nevertheless, the claws of _Deinocheirus_ could have been a wicked 
deterrent against a predator approaching too closely. 


> (I'm quite fond of making the therizinosaur-ground sloth analogy, and before 
> me Russell & Russell did the therizinosaur-chalicothere 
> analogy. Hard to disprove, as we can't directly observe the behavior of 
> either member of the pair... :-S 


I had reasoned that the hand-claws of therizinosaurs (at least in the 
more derived species) were used predominantly for defense.  After all, 
it's not like these pot-bellied theropods could run from danger.  And 
especially in _Therizinosaurus_ the claws do not seem to be the right 
shape for grasping or hooking branches.  I like Robert's description 
of them as "freddy-kruger hands". 


The forelimbs of _Deinocheirus_ and _Gigantoraptor_ might have been 
used in the same way - as defensive weapons.  In the transition from 
carnivory to herbivory it might have been useful to retain long, 
clawed forelimbs for defense.  Though _Gigantoraptor_ was fairly 
cursorial for its size, and the same might have been true for 
_Deinocheirus_ if it arose from ornithomimosaur stock.  But the larger 
therizinosaurs probably had no choice but to hold their ground. 






Cheers 

Tim