Re: Doesn't George have a point?

["Jerry D. Harris" <dinogami@hotmail.com>]

> What I'm asking is really simple.  Is it in line with
> prevailing standards of scientific analysis of
> prehistoric life to hypothesize that birds are
> dinosaur descendants when the dinosaurs the birds are
> said to have descended from come after the first birds
> in the known fossil record

  OK, two things here:

(1) Who said dromaeosaurids were avian _ancestors_?  Last I understood, they 
were considered the _sister_group_, but not actual ancestors. Thus, the 
common ancestor of both birds and dromaeosaurids must have been present 
prior to _Archaeopteryx_; _not_ necessarily that dromaeosaurids go back that 
far (although this brings up when one would call something stemming off from 
that ancestor a "dromaeosaurid"...)

(2) Read more literature.  Chris Brochu and Mark Norell penned a great 
article on this very issue, which _was_ discussed on this list, and showed 
that there really _isn't_ a gap:

Brochu, C.A. and Norell, M.A. 2000. Temporal congruence and the origin of 
birds. _Journal of Vertebrate Paleontology_ 20(1): 197-200.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris

AS OF JULY 1, 2000:

Dept of Earth & Environmental Science
University of Pennsylvania
240 S 33rd St
Philadelphia PA  19104-6316

Phone: (215) 898-5630
Fax: (215) 898-0964

E-mail: jdharris@sas.upenn.edu
and     dinogami@hotmail.com

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