RE: The Importance of Being Extinct (was: Re: phyletic bracketing]

["Jordan Mallon" <j_mallon@hotmail.com>]

> From: "Jonathan R. Wagner" <jonathan.r.wagner@mail.utexas.edu>

> why is everyone taking the lips off of thereopods when no paper has been 
> published?

Tracy Ford published a decent paper outlining his take on the theropod lip 
issue here:
Ford, T. L.  1997.  Did Theropods have Lizard Lips? Southwest 
Paleontological Symposium ? Proceedings, 1997: 65-78.

> The current favorite among American paleontologists is a
> phylogenetic method, wherein parsimony-based character reconstruction is
> used to infer the ancestral state at a the first node ancestral to the 
> taxon
> of interest which has at least two extant descendant lineages in which the
> presence or absence of the unpreservable (or simply unpreserved) trait can
> be established under parsimony.

The two lineages needn't even be extant, as Witmer points out in his paper 
the significance of Lagerstatten fossils in the preservation of soft tissue 
information.  In some instances, Lagerstatten fossils can help to render 
some ambiguous EPB's more decisive and narrow the phylogenetic focus.

Great post, Jonathan.

Jordan Mallon

Undergraduate Student, Carleton University
Vertebrate Paleontology & Paleoecology

Paleoart website: http://www.geocities.com/paleoportfolio/
http://dino.lm.com/artists/display.php?name=Mallon
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