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RE: 11th specimen of Archaeopteryx

> Date: Mon, 31 Oct 2011 00:05:00 -0400
> From: d_ohmes@yahoo.com
> To: dinosaur@usc.edu
> Subject: Re: 11th specimen of Archaeopteryx
> On 10/30/2011 10:50 PM, Tim Williams wrote:

> > I certainly agree with you here. The "limited powerstroke" was not a
> > good recipe for fighting against the force of gravity (which is the
> > essence of "gound-up").
> What, then? Cliffs?
If I didn't know Archie's habitat was composed of islands with scattered trees, 
I'd suggest kjopes to that - vertical boulders and large rocks.  Or maybe 
mountains and scrubland - making cinema-worthy leaps off hillsides to the 
ground below.

> Date: Mon, 31 Oct 2011 16:10:23 +1100
> From: tijawi@gmail.com
> To: dinosaur@usc.edu
> Subject: Re: 11th specimen of Archaeopteryx
> Don Ohmes <d_ohmes@yahoo.com> wrote:
> >> Secondly, if theropods *routinely* spent time in trees we might expect
> >> to see arboreal specializations.
> >
> > Not if the time spent was unrelated to locomotive activity. As in, roosting
> > -- but not foraging, mating and etc.
> I would have said roosting was related to locomotive activity, insofar
> as the animal would be sitting, standing or perching on (or in) the
> tree for long periods. That means that it has to adopt a stable
> posture while sleeping or resting. There is no evidence in the
> anatomies of _Archaeopteryx_ or any non-avian theropod that they were
> capable of this. How did they prevent themselves from toppling off a
> limb, when the manus and pes had minimal (if any) prehensile
> abilities?
Neither do leopards - and those cats sleep in trees.  Or rather, on the tree 
 Just need good balance, is all.
> Besides, I still don't see how tree-climbing qualified as a refuge for
> small paravians, when so many potential predators were large - at
> least as large as many tall trees.
True...but how many of the potential predators wanted a mouthful of tree branch 
half the times they tried biting the paravian?