Bipedality

[Jeffrey Martz <martz@holly.ColoState.EDU>]

     I think I sent this posting out poreviously on Saturday when the 
list died, so I'll try again. 

[Jeff is right; I have what looks to be a previous version of this
 message.  I forwarded it back to USC for distribution, but USC dumped
 it after that.  If anyone else sent a message Friday night or Saturday
 morning and it didn't go through, write to me and I'll see if I have
 it (I could go through and compare my records of "approved"
 vs. "received via the list", but it would be tedious and I'd rather
 not do it if I don't have to; I'd rather do it one message at a
 time.)  Jeff, if you want to see your original (in fact I think I
 might have a couple of yours), just ask. -- MR ]

     I recall that George Olshevsky noted in an earlier posting that the 
switch over to a bipedal stance occured not so much for flight or 
climbing as to dissasociate the forelimbs from respiration.  Exactly how 
would this work, and why wouldn't this be equally advantageous for a 
ground dwelling animal?
     Also, if different theropod groups were really the result of 
different radiations of "dino-birds" continuing into the Jurassic and 
Cretaceous, for which we have no fossils, wouldn't that mean that 
theropod groups would show a lot of features homologous with these 
hypothetical groups that do NOT EXIST in any other theropod group?  Do 
any homologies exist between theropod groups that cannot be explained 
unless you consider that theropods are descended from other theropods? 
     I also want to say I think that easily defensable and logical stories   
are very easy to come up with and defend when the evidence is scanty.  
For an example: The Hell Creek Formation appears to have been a forested 
environment similar to the east coast today.  T.rex is likely to have 
been an active predator.  Therefore, one could speculate that T.rex's 
coloring was camoflaged.  Does this make sense?  Sure.  Is it the "best 
idea going?"  Maybee, who knows?  Would I call it a scientific therory?  
Definitely not.  
  
LN Jeff
"Today was great.  Chaos is great!  Chaos is what killed the dinosaus!"