Re: BIRD CHARACTERISITICS

[Jack <jconrad@lib.drury.edu>]

> distinctly avian characteristics.
> 
> 1) large sternum with a deep furcula (keel) attached to long ribs and
> elongated coracoid bones.
> 2) shoulder girdle rotated and shifted upward, even with the backbone.
> 3) elongated lower leg bones and a modified ankle (tarso-metatarsus)
> 4) elongated ilium attached to at least 11 vertebrae and as many as 23.
> 5) ischium and pubis point backward to make room for the sternum.
> 6) short body centered over the feet with breastbone between the knees.
> 7) shortened pygostyle tail.
> 8) merged temporal openings.
> 9) feathers.

Just an honest question (possibly an inane one):
  Flight (a certain level of powered flight) in either the animal or one
of its ancestors could not be considered a criterion in conjunction
with these other for considering an animal a bird?  I realize that
pterosaurs and bats have both developed powered flight, but they lack the
parallel pubis and ischium and other characters listed above.  

jc