RE: How Did Hadrosaurs Survive?

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

Tim Donovan wrote:


>  Ceratopsids and ankylosaurs obviously had to become larger, but why
> did  Edmontosaurus become so large?-it very likely didn't fight but fled.
> Unless  the longer legs of a larger hadrosaur made it faster, large size 
> would have been a disadvantage.

Who says?  Large size is a wonderful defense for herbivores against large
predators.  I think even Bakker (and I get the impression you've read a lot
of his work) has even suggested this.


>   Albertosaurus was not the immediate ancestor of T. rex. Its ancestor
> must  have evolved inland-as it is unknown in the Horseshoe Canyon. 
> Finally, T.  rex spread to the lowlands, displacing the albertosaurs and 
> forcing the herbivores to become larger-those that could adapt.

Wow!  You've solved the phylogeny, biogeography and ecomorphology of
tyrannosaurs in one swoop.   Why are those professionals so far behind?



Tim