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Re: Today Cordillera, tomorrow the world.
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
How far might they have gotten in the latest Maastrichtian, when seaways
How much of this animal is known?
the tentative identification of Thescelosaurus from Romania.<
In addition to a probable America-Europe link<
I thought that this was more than probable...more like, "Widely accepted."
Am I this far behind on paleogeography?
Tarascosaurus, in particular, supports a Europe-Africa connection, inasmuch
as abelisaurs are otherwise known only from Gondwana.<
Would the presence of _Baryonx_ in England, with the ocurance of other
spinosaurs in Africa strengthen this (despite it being earlier)?
Krause et al determined that virtually all extant Malagasy vertebrates
arrived post-Cretaceous, undermining the notion of an isolated Madagascar
by the latest Cretaceous.<
How does this eliminate an Ice Age land bridge?
Czerkas once mentioned probable South American tyrannosaurs, based on
"fragmentary fossils." This seems unverified<
And therefore not very strong evidence.
but together with Notoceratops is intriguing<
If there, why not the Eastern US?
Cousin et al wrote "...theropods were briefly the dominant group<
Really? So there were predatory stegosaurs beforehand, and after? What other
predators would be dominant in SA then?
That is intriguing as it suggests an alternative to climatic change as the
cause of the extinction of Ampelosaurus, Rhabdodon, and Struthiosaurus.<
What's the alternative? _T. rex_?
Composed mostly of weak defenders, the w. European menagerie seems highly
vulnerable, and its demise foreshadowed extinction elsewhere.<
Hadrosaurs don't seem to be cut out well for defense, yet they survived
through several tyrannosaurids (_Gorgosaurus_, _Albertosaurus_, _T. rex_),
not to mention other predators. I don't see how the vulnerability of an
extinct animal can be stated, and then used as a reason for extintion.
Did this make sense? I'm tired, and getting ready to head to Utah for the
Student of Geology
Northern Arizona University
P.O. Box 20840
Flagstaff, Az. 86011
"A _Coelophysis_ with feathers?"
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