RE: How Did Hadrosaurs Survive?

["Williams, Tim" <TiJaWi@agron.iastate.edu>]

Tim Donovan wrote:


> New species, including predators, are said to evolve in isolation, then 
> spread. 

Allopatry is one possible hypothesis.  It's not the only one.

>The advent of Tyrannosaurus apparently resulted in the extinction of 
> various Edmontonian taxa least able  to fight it or evade it e.g. 
> Euoplocephalus, which was replaced by a larger Lancian defender.

I'd like to see your evidence that proves, beyond all doubt, that
_Tyrannosaurus_ evolved in Asia, not in North America.



Tim W.