RE: Sapeornis and other Mesozoic Birds

[Dino Guy Ralph <dinoguy@sbcglobal.net>]

Oops!  (A typical follow-up my every post requires, it seems).

I meant to ask if _Sapeornis_ was the largest known Early Cretaceous bird,
not the largest known Early Mesozoic bird.  Sorry about that!  

Of course, if flightless dromaeosaurs are birds, then _Utahraptor_ would be
in the running for really big Mesozoic birds.  But I was aiming for a less
inclusive definition of birds for the sake of easy museum visitor
comprehension, whether or not such a group should ultimately turn out to be
a valid clade.  The 10th _Archaeopteryx_ and the southern hemisphere
maniraptora are certainly shaking up the family tree.  It's enough to upset
traditional Arbor Day celebrations. 

I find it amusing that Chiappe writes in _Encyclopedia of Dinosaurs_:
"_Aves_ (birds) may be defined as _Archaeopteryx_ plus extinct birds and all
descendants of their most recent common ancestor (AVIALAE of Gauthier
1996)."  But wait -- how do we know what animals are "extinct birds"?  We
MAY define _Aves_ (birds) as above, but would that really be such a good
idea? 

Confused and loving it,
----Ralph
           

Dino Guy Ralph
Docent at the California Academy of Sciences
Dinosaur and Fossil Education
Member of the Society of Vertebrate Paleontology

-----Original Message-----
From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] On Behalf Of T.
Michael Keesey
Sent: Thursday, August 31, 2006 3:12 PM
To: dinosaur@usc.edu
Subject: Re: Sapeornis and other Mesozoic Birds

> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]On Behalf Of
> Ralph Miller
>
> The largest known EARLY Mesozoic bird?

Seeing as the midpoint of the Mesozoic is somewhere in the
Kimmeridgian, I'm not sure that even _Archaeopteryx_ counts as an
early Mesozoic bird. In fact, you'd probably have to be a bit loose
with your definition of "bird" for there to be any early Mesozoic
birds all. (Well, that or be loose with your definition of "early
Mesozoic".)
-- 
T. Michael Keesey
The Dinosauricon: http://dino.lm.com
Parry & Carney: http://parryandcarney.com