Re: Theropod Postcranial Isolation

["Jerry D. Harris" <jharris@dixie.edu>]

Jaime wrote:

> As an example of dry description, just read the short-form _Nature_ paper 
> on
> *Sinosauropteryx*. Indications of what is what is in the description are
> lacking. Compare to Senter's thesis and resulting analysis of Diapsid 
> phylogeny
> and dromaeosaurid phylogeny, which provide figures of the character states 
> in
> his analysis, a practice I wish all systematists working in morphology 
> would
> use because it would implicitly indicate the variation from an immediately
> visual experience, and allow comparative coding for the test of the 
> analysis'
> results. (like, what's the cut off between an "L"-shaped versus a 
> "7"-shaped
> lachrymal? Degree of angle? Measured from which point to which point across
> which similarly measured axis?

   I'm with you on two of your three points here:

(1) I also wish that more figures would be used in papers; and

(2) Characters defined with vague and ambiguous phrases require 
clarification -- e.g., it's not difficult to state an angle at which "L" 
becomes "7" shaped.  However, having investigated characters of this ilk in 
the past (some such observations are in press), quantifying stuff like that 
can be equally problematic.  If one defined the angle between "L" and "7" 
as, say, "less that 75 degrees," what happens when you have two specimens, 
one with a 76 degree angle and one with a 74 degree angle but that are 
thought otherwise to represent the same taxon?  Individual variation can 
take its toll.  Moreover, does _anything_ along a lineage that possesses a 
"greater than 75 degree" angle necessarily constitute a reversal, even if 
it's greater only by a couple of degrees?  In the end, there's the actual 
wording and attendant quantification of a character, and then there's the 
"spirit" of the character, and coding based on pure numbers untempered by a 
broader understanding by the coder has the potential of producing false 
dichotomies.

   What I do not agree with you on is the (probably unintentional) blaming 
on the researchers and authors of papers for not using figures.  Don't blame 
us -- most of us would really LOVE to include more figures (as well as color 
figures, etc.).  Blame instead the publishers that impose page limits and 
other restrictions for the sake of cost.  Although like everything else, its 
costs have come down over the years, it's still prohibitively expensive to 
let everyone publish 100+ page, fully-illustrated monographs.  So all us 
authors and researchers are forced, usually against our will, to remove 
informative details from our verbal descriptions and limit figures to just a 
few, really important ones.  Well, OK...I should emend that statement by 
saying that if we want our papers published in widely-distributed, 
relatively easy-to-obtain, high ISI-ranked journals, then we have to make 
these sacrifices -- small press publications can more easily and 
inexpensively handle monographs and the like, but they rarely if ever attain 
the distribution levels and ISI rankings of the big journals.  This has 
absolutely nothing to do with paleontology or science; it's pure 
capitalistic economics.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
and     dinogami@hotmail.com
http://cactus.dixie.edu/jharris/

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the mistakes that can be made in a very
narrow field. -- Niels Bohr

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from outer space would say "I want to
see the manager." -- William Burroughs