Re: BIRD CHARACTERISITICS

[bruce moore <brucem@cts.com>]

Jeffrey Martz wrote:

>      To expand a little, what are the diagnostic charcteristics of
> Aves?
> Again, alternatives not based on the _Archaeopteryx_ &/or theropod
> ancestry theory would also be nice.
>
> LN Jeff
> O-

Feathers."In fact, there are no features of the boy skeleton
Archeaeopteryx that are uniquely avian." Carrol, Vertebrate Paleontology
and Evolution.1988

"Based on the presumed uniqueness of feathers, birds are a monophyletic
group."
Fastovsky, Weishampel, The Evolution and Extinction of the Dinosaurs,
1996

Feathers,Furcula
"it has been considered one of the two saient features of the class Aves
(the other being feathers). Fedducia,  The Origin and Evolution of
Birds, 1996

"The taxon traditionally ranked as the "Class" Aves is monophyletic
group united by 12 postulated synapomorphies"
Feathers, furcula, complete calcaneo-astragular fusion, parital fusion
of distal tarsals to metatarsals, Fusion of metatarsals at their
proximal end, moderately retroverted pubis,loss of scapulo-coarcoaid
fusion, postorbital bone greatly reduced or lost, loss of
quadratojugal-squamosal articulation, fusion of joint beween the
sequamosal and occipital complex, caudal vertebrae fewer than 25,
rotation of forelimb. Cracraft, Paleobiology 12(4), 1986, pp383


Bruce Moore