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RE: Campbell's even crazier than a MANIAC? (archeopteryx climbing)



> of _Archaeopteryx_ is not very well adapted to perching. 
> The hallux is not reversed, and it is still quite short and
> high on the foot compared to later birds.  This would make
> it very difficult for _Archaeopteryx_ to land on top of a
> bush.  Difficult, but not impossible - but unusual if these
> kind of landings were habitual. 

Didn't archie have an enlarged claw as well, although not a true "sicle claw"? 
What was the tree bark like at the time?
squirrels climb right up the side of pine trees just fine without any perching 
adaptations, and often jump from limb to limb, at least when frightened.

Perhaps a specialized perching foot like modern birds have wouldn't come along 
until the flight prowess to make spot landings with finesse was there.

Many gliding species today just seem to crash into a mass of branches, and grab 
something, on a regular basis. I think its a bad assumption that archie's 
landings were anything resembling "pretty".


Here's a question... many fish capture prey by rapidly opening their mouths and 
sucking the prey in...

Is it plausible that some insectivore would develop a similar feeding method, 
with air as the medium, not water?

Could something like archie have held its feathered limbs straight forward, 
palms facing each other and in a single action rapidly seperate its limbs - 
sucking an insect towards it, as it lunges forwardwith its neck and head? 

Does the skeletal evidence (and likely muscle attachments) support that 
possibility?

Has it been proposed? or are the only explanations offered so far for "half a 
wing" (before regular flight and gliding evolved) "mating displays" and 
"parachutes to make falls from trees softer"


--- On Wed, 9/3/08, Tim Williams <twilliams_alpha@hotmail.com> wrote:

> From: Tim Williams <twilliams_alpha@hotmail.com>
> Subject: RE: Campbell's even crazier than a MANIAC? (archeopteryx climbing)
> To: dinosaur@usc.edu, twilliams_alpha@hotmail.com
> Date: Wednesday, September 3, 2008, 5:21 PM
> Scott Selberg wrote:
> 
> 
> > It has been postulated that the hind wings of
> Microraptor were carried below the animal and were used
> to> help it steer or take tighter turns, and that
> it's sickle claw was used to help it climb trees.IF it
> turns out 
> > that Archie's environment was in fact low lying
> bushes as opposed to the dense forrest environment 
> > postulated for Microraptor, it would have reduced hind
> wings and a reduced sickle claw since instead of 
> > steering around trees or landing on tree trunks it
> could burst ten or twelve feet into the air and land on 
> > top of a bush, thus reducing the need for tight
> steering or a heavy duty crampon.
> 
> 
> One potential problem with this scenario is that the foot
> of _Archaeopteryx_ is not very well adapted to perching. 
> The hallux is not reversed, and it is still quite short and
> high on the foot compared to later birds.  This would make
> it very difficult for _Archaeopteryx_ to land on top of a
> bush.  Difficult, but not impossible - but unusual if these
> kind of landings were habitual.  
> 
> 
> Also, a bush would be more difficult to land on (and launch
> from) than a large tree because the thin branches would be
> harder to grasp than a thick and sturdy bough.  Especially
> if the foot is not specialized for perching (as is the case
> for _Archaeopteryx).
> 
> 
> Cheers
> 
> Tim
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