From: "David Marjanovic" <david.marjanovic@gmx.at>
Reply-To: david.marjanovic@gmx.at
To: "The Dinosaur Mailing List" <dinosaur@usc.edu>
Subject: Re: Continental predators, etc.
Date: Fri, 31 Aug 2001 15:58:45 +0200
> > Generally speaking prospective prey will often be "aggressive" when
> > flight is not practicable. This is often successful since predators
> > will, generally speaking, avoid attacking any prey which is even
> > moderately dangerous.
>
> Yes, if they have a choice. This is often not the case, however. The
> fossil record is loaded with evidence of "arms races". Such escalation
> could only occur if envelopes were being pushed.
I can't think of _unequivocal_ fossil evidence of arms races at the moment.
The most famous example, the cursorial adaptations of horses, are regarded
by ?some as adaptations for migrating rather than running.