[CPN] Some thoughts on how to address the Cellinese et al. species proposal

Kevin Padian kpadian at berkeley.edu
Sun Feb 5 17:46:58 EST 2012


Dear Colleagues,

There has been no discussion of the Cellinese et al. proposal on the CPN
listserv for some time.  Perhaps everyone has said his or her piece?  I am
finding email an unsatisfactory way to resolve these problems, and I would
ask again that people consider some kind of meeting at which this and
other proposals can be raised and discussed.  Or, at least, let’s set an
“election day” on which to terminate comments and take votes.  (Please,
not “Super Tuesday” …)

I would like to revive the discussion of the Cellinese et al. proposal. 
We have seen Phil and Michel propose modifications to the PhyloCode about
the definition of species, but this does not address the proposal, which
was to remove species as a special rank in PhyloCode.  This is what we
should be voting on, I think, not merely how to reword some articles of
the Code.

There are other points of view in the systematic community, and in my view
it would be good to consider them in order to make sure that there is a
broad enfranchisement of positions.  Referring to Phil's first point about
a broader glossary definition of species: for a lot of taxonomists,
species don't need to be defined in the Phylocode by ANY definition.  We
don't define genera, families, etc.  To do so, in the view of many, just
clouds the issue.  If we remove any legal use of species names in the
PhyloCode we can keep it purely focused on naming clades, and leave the
species controversy aside.  The whole issue of species concepts is just a
tar baby; it is far more productive for biologists to discuss how new
lineages form in different groups of organisms, and then recognize
subdivisions of lineages (including the arbitrary concept “species”) as
particular to those groups.  Taxonomy is, in a sense, bookkeeping; such
accounting procedures can’t adequately encompass the processes and
patterns that describe the splitting of lineages.

One of the most important points of the Cellinese et al. proposal is to
remove the use of species names as specifiers.  They discuss reasons for
this in their Systematic Biology paper, including the need for the
Phylocode to be independent from the existing codes.  It would make sense
if the PhyloCode could allow the mention of an existing species name as a
specifier as a short cut for referring to its type specimen.  But the type
specimen should be the legal specifier, not the name.

In his discussion of Rec. 9c, Phil says:
        "Often the entities that one needs to determine whether they
belong to a particular clade are not specimens but, rather,
species or clades.  I therefore suggest the following wording:
        In order to facilitate the referral of less inclusive clades, as
well as species and specimens that are not specifiers of the clade
name, the protologue should include a description, diagnosis, or
list of synapomorphies."

But Cellinese et al. are saying precisely that traditional Linnaean taxa,
including species, can never be precisely compared to clades named under
the PhyloCode, given that they only have one specifier.  I don't think
anyone on the CPN could disagree with this -- it is basically the main
reason why we all want the Phylocode.  So species should be left out of
this.  It could read:  "In order to facilitate the referral of less
inclusive clades, as well as specimens that are not specifiers of the
clade name, the protologue should include a description, diagnosis, or
list of synapomorphies."

Phil does not include genera or families as specifiers in his suggested
wordings, only species.  It is implicitly rank-based thinking to single
out the species rank for special treatment, and this seems contradictory
to the principles of the PhyloCode.

So, on balance, I think that the approaches that Phil and others have
suggested to the proposal by Cellinese et al. do not address their central
point, but rather shelve it and simply tinker with other wording.  I am
not in favor of the modifications that Phil and Michel suggest for this
reason.  I don't know what a species is, any more than I know what an
order is.

The question is to remove species as ranks with special privilege.  Yes or
no?




-- 
Kevin Padian
Department of Integrative Biology &
Museum of Paleontology
University of California, Berkeley CA 94720-3140
510-642-7434
http://www.ucmp.berkeley.edu/people/padian/home.php




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