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RE: Deinonychus claw, er, no, still Catch-22, really...






> Date: Fri, 16 Dec 2011 15:01:31 +1100
> From: tijawi@gmail.com
> To: dinosaur@usc.edu
> Subject: Re: Deinonychus claw, er, no, still Catch-22, really...
> 
> Don Ohmes <d_ohmes@yahoo.com> wrote:
> 
> >> Even if (and it is still an*if*) certain characters in
> >> the hands and feet improved trunk-climbing or branch-holding ability,
> >> these characters must be set against the rest of the skeleton, which
> >> remained resolutely terrestrial.
> >
> > Why? The same can be said of birds.
> Birds can fly up from the ground into a tree. Flight removed the need
> to climb. Aside from the juveniles of a few species (such as the
> hoatzin), no bird is an arboreal quadruped. 
 
 with the possible exception of Microraptor, neither were Theropods.
 
 
> >> Theropods lacked the flexible
> >> vertebral columns and range of motion at the joints which, by and
> >> large, are present in mammals.
> >
> > And theropods need these traits to climb vertically or roost? Why?
> 
> I was using these traits to demonstrate that theropods are/were not
> like mammals - or lepidosaurs or turtles,
 
 good point - after all, if anything has a stiffer spine than theropods, it 
would be turtles.
 
> for that matter. Simply
> because goats and certain turtles can (and do) climb trees does not
> mean that it was as easy for theropods. The "even goats can climb
> trees, why not dinosaurs?" analogy is unhelpful for so many reasons.
 
 except you're the only one who keeps bringing up goats.
 
 
> > No one argues (in this thread) that theropods were arboreal - or if they
> > did, I missed it...
> No, you didn't miss it. But if we going to put non-avian theropods in
> trees (such as to sleep, seek refuge, or perch-hunt), I want to see
> *positive evidence* for an ability to climb or roost in trees.
 
Well, there was a dinosaur-written confession engraved on a tyrannosaurid bone 
found back in the 1830s, giving abundant evidence for those very abilities.  
unfortunately nobody believed it because it was written in Ubykh.