RE: How Did Hadrosaurs Survive? (Was: Hadrosaur "mummy" questions)

[Nick Pharris <npharris@umich.edu>]

Quoting Tim Donovan <msdonovan66@hotmail.com>:

>    There is evidence that tyrannosaurs attacked armored dinosaurs, and 
> perhaps ceratopsids, which are much more dangerous or tougher than 
> hadrosaurs. Also, if tyrannosaurs did not dare attack healthy adults, why 
> did ceratopsids and ankylosaurs evolve greater size to match T. rex? The 
> average adult size should not have changed if they were generally not 
> targeted.

An observation:  an increase in adult body size *could* potentially be a by-
product of selection for accelerated growth in youngsters, so that they would 
spend less time in the tyrannosaur-snack-size range.

--Nick P.