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RE: Campbell's even crazier than a MANIAC? (archeopteryx



> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] 
> On Behalf Of Jeff Hecht
> Sent: Thursday, September 25, 2008 10:35 AM
> To: tholtz@geol.umd.edu; augustoharo@gmail.com
> Cc: dinosaur@usc.edu
> Subject: Re: Campbell's even crazier than a MANIAC? (archeopteryx
> 
> Do you define "all" as all Aves, or all Neornithes? That's an 
> important question because we don't know why other Aves did 
> not survive past the end of the Cretaceous. A difference in 
> flight capabilities might explain the difference, or perhaps 
> the differences lie in other capabilities which are hard to 
> spot in the fossil record, such as metabolism. 
> 
> At 8:02 PM -0400 9/24/08, tholtz@geol.umd.edu wrote:
> >> Perhaps all the Cretaceous birds were not better flyers 
> than tinamous 
> >> and chickens??.
> >
> >I think that this is really closer to the truth than most people 
> >consider at the present...
> >

For myself, I think that far too many people extrapolate a neoavian
(non-tinamou, non-galliform) flight ability too far down within the history
of birds. Based on flight distribution of living birds, I consider it quite
likely that good long distance flight may have been limited to anseriforms
(and not sure how far down it goes among these) and in Neoaves, and that
basal members of Aves/Neornithes may have had a more limited flight scope.
But as the long term success of (among others) galliforms show, being a
successful flying bird doesn't mean you have to fly as well as a crow, hawk,
or heron!!

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661               

Faculty Director, Earth, Life & Time Program, College Park Scholars
http://www.geol.umd.edu/~jmerck/eltsite/
Fax: 301-405-0796

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA