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Re: "Early" cretaceous Tyrannosaurids

> The Japanese news shows that fossil discovered last year at
> the Tetori Group (Lower Cretaceous) of Fukui in Japan was judged to be
> the premaxilla tooth of tyrannosaurids.
>           According to M.Manabe (National Science Museum), as for the
> tooth of tyrannosaurids, it is the first fossil discovered in Japan
> and is the oldest in the world. Fossil is about 1 cm in the length and
> about 5 mm in width and it's horizontal section is D type. Different
> from other carnivorous dinosaurs, it's characteristic only of tyranno-
> saurids.
>           Last year, the fossil of tyrannosaurids was found at the
> stratum of Lower Cretaceous in Thailand. A hypothesis that
> Tyrannosaurids
> evolved in Asia and went into the North America was proposed.
> Manabe said the fossil of this time may prove this Asia origin theory
> of tyrannosaurids.

        You might be interested that I gave a talk at SVP in New York 
(JVP 14(3) Abstracts, p. 45 A) where I report on the occurrence of 
hadrosaurs, ceratopsians, and tyrannosaurs from the base of the 
Cenomanian  in Utah. I propose this is the earliest date for opening 
land connections to Asia through Alaska. The Asian imigrants nearly 
totally replace the preexisting late Early Cretaceous fauna of NA.

Jim Kirkland
Dinamation Int'l Soc.