Fwd: PhyloCode and "the real world"

[Philip Cantino]

Mark Garland wrote:

>Reading this thread, I wondered what future floras and faunas would look like
>under the PhyloCode.  (Thinking from my ignorant user's perspective).  I
>supposed we would have keys to clades, but couldn't figure out how you'd
>choose the clades to key to.  The ones you feel like making a key for?  The
>ones that are phenetically distinct?  Which clades would you present in a
>textbook?

Although I said earlier that I would probably continue to use
Linnaean nomenclature for floristics, it occurs to me that an
advantage of phylogenetic nomenclature in this context is that there
is no requirement that any particular clade be recognized in a
classification or included in a key.  In contrast, the rank-based
system requires that every species be assigned to certain standard
ranks.  Thus, a flora must include every family that is represented
in the geographic area covered, even if some of them are difficult to
distinguish.  In contrast, the use of phylogenetic nomenclature in a
flora offers greater flexibility.  A flora writer could organize a
flora using phenetically distinctive clades that include enough
species in the geographic area covered to be useful in
organization and memory.  Clades that are less distinctive and/or
locally monospecific could be ignored.  This flexibility might well
make it easier to write and use keys.

Many of the clades in a key using phylogenetic nomenclature
would no doubt correspond to genera and families under the rank-based
system, but some would probably correspond to subfamilies, subgenera,
etc. or have no counterpart.  Because of our traditional emphasis on
families and genera, taxa that happen to have intermediate ranks are
often ignored in floras even when they are quite distinctive and
therefore potentially helpful in the keying process.  One reason for
this, I suspect, is the convention that if one subfamily (for
example) is used in a classification, then every species in that
family must be assigned to a subfamily.  It is often the case that a
few subfamilies of a family (or subgenera of a genus) are distinctive
but the others are not.  Faced with an all or none requirement, the
path of least resistance is to omit all of them.  This kind of choice
is not necessary in phylogenetic nomenclature; you can include the
distinctive clades in your classification and ignore the ones that
are difficult to distinguish.



>
>But from the comment above I see that there will be a PhyloZone (tm) within
>which the PhyloCode *will* be used, and everywhere else, where it will *not*
>be used.  Phew!  That's a relief.  But wait--who sets the boundary of the
>PhyloZone?

The boundaries will be determined by the users themselves--i.e., by
common practice.  (There will be no PhyloCzar dictating the boundary
of the PhyloZone.)

Phil

Philip D. Cantino
Professor and Chair
Department of Environmental and Plant Biology
Ohio University
Athens, OH 45701-2979
U.S.A.

Phone: (740) 593-1128; 593-1126
Fax: (740) 593-1130
e-mail: cantino at ohio.edu