Re: If the asteroid had missed...

[Michael Habib <mhabib5@jhmi.edu>]

On Wednesday, March 14, 2007, at 08:33 AM, jbois@verizon.net wrote:

> Dinosaurs are still here...they are just no longer competitive in the 
> large animal niche.  Predatory tactics of birds, mammals, and reptiles 
> are probably prohibitive for any animal whose nest is dependent upon 
> defending a nest in the open field (crocs having the advantage of 
> ambushing a nest predator _and_ seeing very well at night...a luxury 
> probably not afforded most dinosaurs).

Ah, but here's the rub: even if you are correct, the modern faunal 
composition probably wouldn't exist without the bolide effects, which 
creates a bit of a Catch 22.  Of course, we've debated this point 
before and I know we're in relatively stark disagreement about possible 
causal factors for higher-clade level, global extinction events, as 
well as the relative importance of viviparity in mammals.

Cheers,

--Mike H.


Michael Habib, M.S.
PhD. Candidate
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205
(443) 280 0181
habib@jhmi.edu