Fwd: Re: rankless nomenclature

[Philip Cantino]

Tom Lammers wrote:

>This is all true, and I would like to add the observation that the biggest
>problem is our uncertainty over the phylogeny of nearly all groups of
>organisms, except maybe birds and mammals.  As near as I can see in the
>botanical world, most published phylogenies are absolute
>houses-of-cards.  I simply have too little faith in the power of the
>cladistic method to want to irrevocably hitch our system of nomenclature to
>a cladogram in any sort of rigid lock-step method such as that proposed by
>the PhyloCode.  Talk about feet of clay!  IF we *knew* the "correct"
>phylogeny of a group, if we were privy to God's Master Cladogram, the
>PhyloCode might work OK.  But in the Real World?  It simply won't work.  It
>will cause far more problems than it will cure.  A great idea from a
>theoretical idealistic viewpoint, but for a practicing taxonomist, a
>nightmare.

What is a practicing taxonomist?  In my mind, this term includes not
only the people working on species boundary problems and floristic
studies but also the many systematists who are interested in
phylogenetic relationships above the species level (or do we not
practice but only preach?).  For those of us who are  trying to
document and communicate about phylogeny, the "nightmare" is trying
to name and discuss the clades we have discovered when we are
confined by the strait jacket of a rank-based nomenclatural system
that was not designed for this purpose--a system that often forces us
to change the names of previously named clades in order to name new
ones, or to recognize paraphyletic or monotypic taxa in order to name
clades.

Perhaps phylogenetic nomenclature does not meet your needs, Tom, but
rank-based nomenclature does not meet mine.  The PhyloCode will not
replace the other codes; it will complement them, making the work of
phylogenetic systematists a lot easier.  People who do not find it
useful are welcome to continue using the rank-based system.


>As Doug rightly points out, once
>the application of names is tied to explicit circumscriptions instead of
>types, it is inevitable that name changes will flourish and most familiar
>names will be lost.

As I pointed out in my response to Doug's posting a few minutes ago,
this is simply not true.



>As it stands now, traditional nomenclature has enough "slop" in it that it
>can often be unperturbed by changes in our understanding of
>relationships.  Dropping or adding a taxon here or there upsets no
>one.  Campanulaceae is still Campanulaceae with or without Sphenoclea and
>Pentaphragma.  Under the PhyloCode, it might not.  Where in the world is
>the sense in that?


I don't know much about Campanulaceae, but I assume from the context
that Sphenoclea and Pentaphragma are genera of uncertain phylogenetic
position.  They should therefore not be cited as specifiers in the
definition of the name Campanulaceae (see Recommendation 11B of the
PhyloCode).  If this recommendation is followed, the name
Campanulaceae will be unaffected by the position of Sphenoclea and
Pentaphragma.  They can be excluded or included in the Campanulaceae
based on the proponderance of evidence, but the name will remain the
same.

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