Re: How Did Hadrosaurs Survive?

[John Conway <john_conway@mac.com>]

On Tuesday, October 29, 2002, at 10:26  PM, Tim Donovan wrote:

>   Newly introducd predators have devastated some ecosystems. The brown 
> tree snake wiped out nearly all of the native birds on Guam. New 
> species, including predators, are said to evolve in isolation, then 
> spread. Essentially there may be little difference between the effects 
> of a newly evolved predator and a newly introduced 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.

There is a BIG difference between the effects of a "newly evolved" 
predator and a newly introduced one. Evolution of a predator gives time 
for an evolutionary response from prey. Predators do not evolve in a 
vacuum. For this reason I take exception to the line "advent of 
Tyrannosaurus", as if Tyrannosaurus just "arrived". Tyrannosaurus 
evolved alongside hadrosaurids, and hadrosaurids with it - show me the 
fauna with tyrannosaurids but no hadrosaurids.

Euoplocephalus was one of the LEAST able to defend itself?! What 
possible reason could there be for thinking so? Such a statement seems 
manifestly absurd.


John Conway, Palaeoartist

"Do I contradict myself? Very well, then I contradict myself, I am 
large, I contain multitudes." - Walt Whitman

Systematic ramblings: http://homepage.mac.com/john_conway/
Palaeoart: http://homepage.mac.com/john_conway/_palaeoart.html
Skeletals: http://homepage.mac.com/john_conway/_skeletals/