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Re: Critique of a critique



Philidor11 wrote-
 
> <I know of nothing in Chiappe et al. which conflicts with recent work, when that work is correct.>
 
> Doesn't that mean when it agrees with Chiappe et al.?  Small point, but I wanted to point out
> that you did describe a perfect circle.
 
No, I meant the only times it conflicts with recent work is when that work is done by ABSRD proponents to try to argue birds are not dinosaurs.  For instance, Hou et al. (1999) argue since the semilunate carpal only fuses to the second metacarpal, it must be derived from a single distal carpal.  This simply doesn't follow logic.  The semilunate still articulates with metacarpal I, so it's not reduced in size compared to Archaeopteryx and other coelurosaurs.  There is no evidence suggesting the semilunate of birds isn't formed from distal carpals I and II, unless you want them to seem less maniraptoran.  Same for the upright posture, differently numbered manual digits, etc..
 
> Anyway, more significantly, I was intrigued by the statement that:
<I would suggest that the reason Confuciusornis is the most abundant bird in the deposit is >because flocks of them were flying over the lake when disaster struck. There can be little
>doubt that the principal means of locomotion of Confuciusornis was flight. This is a most >important fact because it was flying with a primitive, fused scapulocoracoid without an >enlarged acrocoracoid process, it was flying without a keeled sternum, it was flying without >an alula, and it apparently was flying without a fully modern avian wrist. Confuciusornis >shows us, therefore, that we should not posit the highly refined aspects of modern birds as >being requisite for active flapping flight. It also removes virtually all of the objections to >Archaeopteryx being capable of active flight.>
 
>Would you agree with this statement?  Including the observation about Archie?  Tenuous >inferences...
 
I don't know enough about taphonomy to speculate why so many confuciusornithids are preserved so completely at Liaoning.  I think Olson ignores some good evidence presented by Chiappe et al. that suggest Confuciusornis was intermediate between perching and terrestrial birds in morphology.  Thus, I don't know if the principal means of locomotion was flight or walking.  I do agree that the many basal characters show flapping flight is possible without the array of specializations seen in neornithines.  However, Archaeopteryx is more basal than confuciusornithids in several pectoral and forelimb characters (supracondylar nerve foramen not displaced medially, shorter coracoid, unfused metacarpus, etc.), so was probably a worse flyer.  I still think Archaeopteryx was capable of flapping flight though.
 
Mickey Mortimer