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Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)
> > 5 ft does not seem enough of a vertical drop to
> stimulate the initial
> > transition from a cursorial predatory biped that
> utilizes isolated trees
> > for roosting/nest/perch-hunting to the same, only w/
> an initial
> > parachuting/gliding capacity. Could we change that to
> 5m? :D.
> Maybe not. Some say the vegetation on the islands where
> Archie apparently
> lived was only 3 m high.
I would be happier if we didn't. Anything *above* ground-effect altitude for
Archie (~60 cm or so) is enough.
> However, nesting in trees does not appear to be
> plesiomorphic even for
> crown-group birds.
I have not seen anything to suggest that tree-nesting might precede perching,
and I have seen a lot of arguments against it. *Confuciusornis* makes sense as
a tree-nester. But Archie? Why should it, why would it and how could it?
> > Works especially well in an area where trees are
> well-scattered, and there
> > is little undergrowth.
> There may have been _only_ undergrowth.
This was my point. Any reconstruction of Archie climbing spread-limbed up some
palm tree - FORGET THAT. There is nothing in favor of it, and a lot that speaks
Leg position roughly like this, arms different - humerus ventrally and lower
arms/hands grasping forward, to ascend hand-over-hand a near-vertical slope.
Possible? Was there anything that would have *prevented* it from doing it?
(This is not a mock question; I have not looked into this. Wrong caudal
vertebrae for me, and too many teeth ;-) )
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