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Re: Feathered Dragons: Studies on the Transition from Dinosaurs to Birds
----- Original Message -----
From: "Jaime A. Headden" <qilongia@yahoo.com>
Sent: Monday, April 26, 2004 10:09 PM
> Scott Hartman (DinoBoyGraphics@aol.com) wrote:
>
> <I have to comment on this: There is no reason to think that the
> rectrices on the hind limbs of Microraptor could not fold back against the
> leg during terretrial locomotion: If not, they would have been destroyed
> during anything bu the most limited of arboeal locomotion as well. Also,
> Nick did not conlcude that the feathers on the hind limbs of Archaeoptery
> were anywhere near as long as in Microraptor, although he speculated that
> their presence might indicate that leg "wings" were primitive for the
> group.>
>
> I would also like to say that unless there was a special novel muscular
> anatomy of the legs [...], this is one of the more unparsimonious
arguments
> to assume that these animals were particularly terrestrial _and_ capable
of
> maintaining leg-feather security.
Wait a little. We don't even know if the hindwing feathers stuck out
caudally or laterally!!! In addition, we don't know if they were mobile --
by skin muscles which, by parsimony, almost have to be assumed to have been
_present_.
Months ago I promised to draw a few possibilities I can imagine how a
*Microraptor* uncapable of sprawling could have used its hindwings... I'll
do that, hopefully soon...
> Greg Paul only proposed (without direct evidence) that the femora could
> laterally/dorsally extend to explain leg _flapping_, rather than
> sprawl-legged climbing. Avian femoral orientation laterally from the belly
> has been explained not as a climbing adaptation,
Pardon? Avian femora are fully erect as usual, and can't be abducted to a
significant degree. This is an adaptation for running and _against_
climbing. -- *Microraptor zhaoianus* was incapable of abducting its legs. As
long as I don't see evidence to the contrary, I'll assume that *M. gui*
wasn't different.