Re: Vertebrates? (posted by B. Roth)

[barryr@xxxxxxxxxxxxxxxxxx (Barry Roth)]

A propos of my earlier comment that phylogeny should be more than a sideline
to studies of biostratigraphy, Tom Yancey (tyancey@tamu.edu) wrote:
[...]
>Biostratigraphy is a fundamental area of paleontology - it provides us with
the 
>tools for age determination which make other pursuits possible. Much 
>biostratigraphic work remains to be done, so let's emphasize the importance of 
>sound procedures in biostratigraphy and not subsume the practice into other 
>aspects of the science. Developing good biostratigraphic zones is highly
skilled
>work, with value equal to, or greater than, that of developing good
phylogenies.

I think this view unnecessarily sets biostratigraphy and phylogeny at odds.
"Sound procedures in biostratigraphy" go beyond the mechanistic recognition
that fossils of a certain configuration occur between two datums in the
rocks.  It should include the effort to recognize monophyletic groups as the
basis for zonation.  Paraphyletic groups may suggest unnaturally short or
long ranges, which may lead to spurious correlations.  This argument is well
stated by Padian K, D R Lindberg, P D Polly, 1994, Cladistics and the fossil
record: the uses of history.  Annu. Rev. Earth Planet. Sci. 1994, 22:63-91.

 Barry Roth                             barryr@ucmp1.berkeley.edu
 Research Associate, Museum of Paleontology
 University of California, Berkeley, CA 94117 USA   (415) 387-8538