Re: K-T survivors (hadrosaurs?, mammals & birds)

["Ken Kinman" <kinman@hotmail.com>]

     Just read Dan's post, so I'll quickly respond to that.  Fassett's new 
paper will include the results of rare-earth analysis (a technique which has 
only been used by paleontologists for a few years).  These methods can give 
you a much better idea if bones have been "reworked" or not.
     Now to David's post.  There is no reason to expect an explosion of 
hadrosaur populations.  One or two surviving species could have held on 
within the shrinking fern habitats, as the flowering plants recovered and 
continued their evolutionary radiation.  Many flower plants are notoriously 
successful at fending off herbivores with bad-tasting chemicals, thorns, 
"guard"-ant associations, and other bioweaponry, and hadrosaurs may not have 
been able to adapt to them quickly enough.
     But for all we know, they could have adapted to the plant situation, 
only to succumb to hordes of egg-eaters expanding into their territory.  
There are lots of things that could have kept hadrosaurs from a more 
long-term recovery.  I'm sure there will be plenty of debating over various 
scenarios, assuming that we do find definitive evidence that they did indeed 
survive the K-T.  I have e-mailed Jim Fassett to see if there will be any 
delays in his publication (I hope not).
      ------   Ken Kinman
P.S.  So you see Eric, the expanding importance of molecular evidence does 
not detract from morphological and stratigraphic evidence provided by 
fossils.  It just complements it in a rather synergistic way.  
Paleontologists like Michael Novacek and  Simon Conway-Morris have written 
on the importance of using both kinds of evidence in concert.
*****************************************
David wrote:
> One problem I have with surviving hadrosaurs is the utter lack of evidence
> for an explosion in hadrosaur numbers, even if not in the number of their
> clades (longer generation times than tiny mammals), in the Paleocene. The
> other is how they then died out. Competition from mammals is IMHO very
> unlikely, as, apart from multis, herbivorous mammals were just beginning to
> evolve, and stayed much smaller than any hadrosaur for a long time. Nest
> raiding is just as unlikely for me because there were big carnivorous
> mammals like *Didelphodon* before the K-T, and nothing happened to the
> hadrosaurs then.


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