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

[Cantino, Philip]

I disagree fundamentally with the perspective expressed in Kevin Padian's most recent message, for two reasons:

1) Kevin would like an up or down vote "to remove species as a species rank in PhyloCode".  However his wording here and elsewhere in his message implies that he himself views species as simply a rank, in agreement with Nico et al.   The crux of the problem is that even among the CPN, there are varying views on whether the species category is simply a rank or a kind of biological entity distinct from a clade.  The latter view is adopted in the current version of the code, and I agree with Nico et al. that it is not appropriate for the PhyloCode to endorse a particular concept of the species category.  By the same token, it would not be appropriate to endorse the opposite view that a species is simply a rank.  To do  so would make the PhyloCode unappealing to biologists who consider the species to be more than a rank, just as the current version is unappealing to those who view it as only a rank.  The revised glossary definition I proposed tries to encompass these two views and others, thereby bypassing the "species problem" while still permitting people to use species names as specifiers.

2) Even if we all agreed that the species category is simply a rank, it would not be appropriate to simply vote on the central question of removing any reference to "species" in the code without first considering the practical ramifications of the decision.  What appears to Kevin to be mere tinkering with wording is essential if we are to make a wise decision.  In legal codes even more than in other aspects of life, "the devil is in the details".  When I presented my alternative proposal, I was not intending that it be voted on as a whole.  Rather, I was working out the ramifications of an alternative approach to that proposed by Nico et al., just as they did in their proposal.  Without the details, we really don't know what we are voting on.

A few comments on specific parts of Kevin's message:


On Feb 5, 2012, at 5:46 PM, Kevin Padian wrote:

> 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?

Given the importance of this issue, I hope that everyone on the CPN will weigh in at some point.

> Or, at least, let’s set an
> “election day” on which to terminate comments and take votes.  (Please,
> not “Super Tuesday” …)
> 

It's too early to be setting a date for a vote.  We haven't yet even seen the external comments that David M. received and will send as soon as he has internet again.  This is not a simple decision and it is a very important one.  I think we should permit discussion until such time that everyone agrees that they have said all they want to.  After the external comments are received, if there is another lull in the discussion, I suggest that the CPN chairman ask the members to speak up if they are not yet ready to vote, and give members a few days to do so in case people are away from email.



> 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.  

We don't define genera, families etc. because we all agree that they are simply ranks.  In contrast, some of us (and many biologists outside our small group) view species as more than a rank.  Given the disagreement, I maintain that it is appropriate to provide a glossary definition of the word "species" that is sufficiently broad that it encompasses the range of views, so that users of the code will understand what we mean by "species" where the word appears.  Of course, this is a non-issue if we vote to remove the word entirely from the code, but I very strongly oppose that for the practical reasons I have explained in previous messages.

> 
> 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.
> 

The code already does this.  Note 11.1.1. When a species is cited as a specifier, the implicit specifier is the type of that species name (if a type has been designated) under the appropriate rank-based code. 


> 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.  

I don't think the issue is whether species are comparable to clades in this philosophical sense.  Rather, it is simply that people who use species names want to know whether particular species (whatever they may think a species is) are part of a particular clade.  

> 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."
> 

But what about the needs of biologists who DO consider species to be more than a rank?  Is the PhyloCode a special-purpose tool intended only to serve the needs of the minority of systematists who don't deal with the names of species?  If so, it certainly isn't going to catch on broadly.


> 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.
> 

It is not rank-based thinking if one considers species to be more than a rank, which some of us involved with this project do.  See my Point 1 above.

> 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.  

See my Point 2 above.

> 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?
> 

See my Point 1 above.

Phil