Re: Paleocene dinosaurs (Ref.s)

["David Marjanovic" <david.marjanovic@gmx.at>]

>From the unfair position of not having read the paper, I'd like to add the
following comments:

> "Ornithoid (theropod) eggshells are...abundant and occur in association
> with relatively uncommon sauropod eggshell fragments and denticulated
> theropod teeth...

Teeth are notorious for reworking (there are some in _Miocene_ layers of
France!), and it has been demonstrated (IIRC experimentally) that it's
impossible to tell little transport from no transport. Eggshell _fragments_
can also be reworked AFAIK.

> 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.

Unless the authors have additional evidence, this claim is logically false.
Absence of thin fragile bird bones is negative evidence, see above for the
presence of theropod teeth.
Oviraptorosaurs and dromaeosaurs which had (not totally proven for the
latter) ornithoid eggshells are unknown from India. Of course that's
negative evidence too.

> Furthermore, ostracods include the
> same Cretaceous taxa..which occur...in other dinosaur-bearing
> intertrappean localities."

I'm sure ostracods can be reworked. Does "include" mean that there are
Paleocene ostracods, too, at that site, which would nearly prove reworking?