RE: Starkov's theory and extinction

["R. Irmis" <rbi@dana.ucc.nau.edu>]

<<JVP 20(3) September 2000 -- Abstracts p. 71A:

"CO-ADAPTIVE EVOLUTION: LARGEST THEROPODS AND LARGE SAUROPODS
        STARKOV, Alexei I., Institute of General and Experimental Biology,6
Sakhyanovoi St., Ulan-Ude 670047, Russia
...Appearance of *Tyrannosaurus* in Late Maastrichtian, with its 12 [what
about
14?] m length and no more than 6 tons in weight, has broken this
appropriateness. It may be connected with some qualitative changes of taxa
composition, namely appearance of sauropods which directed the natural
selection to the increase of sizes of tyrannosaurids. As a reaction, sizes
of their usual preys at the Early-and-Late Maastrichtian border increase too
(*Edmontosaurus*, *Torosaurus*, and *Triceratops* are larger than
Campanian-Early Maastrichtian genera by about 15-20%)....>>

Can' this be explained just by Cope's Rule?  Also, *Alamosaurus* probably
was one of the rarer prey in the Maastrichtian fauna, just by virtue of the
fact that it ate more food, and thus the environment could support a smaller
density of *Alamosaurus*.  However, it seems that *Tyrannosaurus* is more
common than once thought.  Seeing as how common Hadrosaurs and Ceratopsians
were, I'm willing to bet that was *T. Rex*s primary prey.

Regards,
Randall Irmis