RE: another dumb question: Terror Birds are not dinosaurs?

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]On Behalf Of
> Paula Goodman
> 
> 
> With all this talk about birds-are-dinosaurs, I'm curious to know what, 
> if anything, distinguishes the bird status of Phorusrhacidae from that 
> of the recently discovered Gigantoraptor, for example. Why do we call 
> one a big bird fossil, and the other a dinosaur fossil?
> 
>

Others have answered with specifics of "what is a dinosaur?" vs. "what is a 
bird?".

Just some things to remember:

All birds are dinosaurs, but not all dinosaurs are birds

in precisely the same fashion as

All bats are mammals, but not all mammals are bats.

                Thomas R. Holtz, Jr.
        Senior Lecturer, Vertebrate Paleontology
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
        Mailing Address:
                Building 237, Room 1117
                College Park, MD  20742  
     
http://www.geol.umd.edu/~tholtz/
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796