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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
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