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Re: Today Cordillera, tomorrow the world.
In a message dated 5/18/01 11:53:05 PM Eastern Daylight Time,
> Ceratopsids were always unknown in the east<
> As mentioned onlist earlier today, absence of evidence is not always
> evidence of absence. With hadrosaurs in the Eastern US, and the Western US
> (all the way to California!), I don't see what would prevent ceratopsids
> migrating across the
Right on! However, I'd like to add that we _DO_ have evidence for
ceratopsians from the Aptian of Maryland in the form of 3 single rooted,
Neoceratopsian teeth from my site (see ref below) as well as yet to be
documented tracks discovered by Ray Stanford. If these hold up as
ceratopsian, this makes them the oldest remains of such in North America. Now
one of my co-authors does not agree with what I am about to say, by I believe
this forces one to reconsider the timing and direction of ceratopsian
migration from a late-K Asian - Berringia route to an earliest K
Eurasian-Canadian Maritime route. Alternately, it could be one of a number of
separate vicariant events. Not enough data to say...
Chinnery, B. J., Lipka, T. R., Kirkland, J. I., Parrish, J. M., and
Brett-Surman, M. K., 1998, Neoceratopsian teeth from the Lower to Middle
Cretaceous of North America, in Lucas, S. G., Kirkland, J. I., and Estep, J.
W., (eds.), Lower and Middle Cretaceous terrestrial ecosystems, New Mexico
Museum of Natural History Bulletin 14, p.297-302.
Lipka, T. R., 1998, The affinities of the enigmatic theropods of the Arundel
Clay facies (Aptian), Potomac Formation, Atlantic Coastal Plain of Maryland
in Lucas, S. G., Kirkland, J. I., and Estep, J. (eds.), Lower and Middle
Cretaceous terrestrial ecosystems, New Mexico Museum of Natural History
Bulletin 14, p.229-234
Can be found on line in their entirety at:
Thomas R. Lipka