Re: phyletic bracketing

["Ken Carpenter" <KCarpenter@dmns.org>]

Kenneth Carpenter, Ph.D.
Curator of Lower Vertebrate Paleontology &
Chief Preparator
Dept. of Earth Sciences
Denver Museum of Natural History 
2001 Colorado Blvd.
Denver, CO 80205

Phone: (303)370-6392
Fax: (303)331-6492
email: KCarpenter@DMNS.org

For fun:
 http://dino.lm.com/artists/display.php?name=Kcarpenter


>>> "David Marjanovic" <david.marjanovic@gmx.at> 07/Apr/04 >>>
> Phyletic bracketing analysis (PBA) has become the latest tool in the
analysis of dinosaur structures and behavior. For example, because guarding
of nests occurs in crocs and in most birds, then nest guarding must have
occurred in dinosaurs

Eh, no. Then _it is most parsimonious_, in other words _most scientific_, to
assume that nest guarding occurred in non-neornithean dinosaurs. As long as
we don't have direct evidence for the contrary.


not according to Horner :-)


> The problem of PBA is that it cannot explain novel structures, and indeed
in the strict adherence to the techniques does not allow for such structures

Correct. Nevertheless, this is scientific -- each assumption that a novel
structure occurred is one more assumption, and science strives to minimize
the number of assumptions.

> (fireworks at this point, I am sure).

No, why? :-)

I just wonder why you suddenly try to begin a discussion on this, seemingly
not in response to anything I've seen onlist recently...

If we cannot start a new discussion, then we would never discuss anything new, 
just the same old cycle of bird origins/feathered dinosaurs, and T. rex this 
and T. rex that. ;-)
Ken