Re: Paleocene dinosaurs (Ref.s)

[John Bois <jbois@umd5.umd.edu>]

On Sun, 14 Oct 2001, Ken Kinman wrote:

> John and George,
>       Even if these eggshells are not reworked (which would probably not be 
> easily proven), if these are indeed "theropod" eggshells, why couldn't they 
> be the eggs of birds (i.e. avian theropod survivors)?   Are they going by 
> estimated size of the eggs or by the shell microstructure?

"Ornithoid (theropod) eggshells are...abundant and occur in association
with relatively uncommon sauropod eggshell fragments and denticulated
theropod teeth...Although there are considerable similarities in the
eggshell structure of theropods and birds..., the presence of theropod
teeth and the total lack of any bird bones rule out the possibility that
these ornithoid egg shells are avian.  Furthermore, ostracods include the
same Cretaceous taxa..which occur...in other dinosaur-bearing
intertrappean localities."