Re: The Holy of Holies... Dinosauria II

["Jonathan R. Wagner" <jonathan.r.wagner@mail.utexas.edu>]

Any taxonomic nomeclature involves ambiguity: when I give a species name, 
am I referring only to the type, or to the type and a collection of 
referred specimens? Am I including all of the referred specimens? What 
about population-level varation? Systematics has not done a very good job 
of addressing this issue. For example, molecular systematists often 
recognize much less inclsive species than morphological systematists 
(unsurprising, considering the resolution of their data). So, while they 
are often recognizing traditional subspecies as species, they have to deal 
with literature that often makes sweeping statements about the morphology, 
physiology, and life-history of the original species, without knowing if 
ANY of the relevant data were gathered from the populations with which they 
are concerned.

Remember, our goal is communication, even with people who use a different 
set of taxonomic rules. By going using generic epithets to refer to 
species, we actually EXPAND this problem: in traditional (Linnean) 
nomenclature, ambiguity actually increases at higher taxonomic ranks. In 
discussing the choice of names to convert for species under the PhyloCode, 
we have already touched on some of these problems (e.g., is this genus 
really monotypic?). By adopting a generic epithet without a species name, 
you would remove a piece of information that actually INCREASES precision 
of information retrieval from the literature. For example, cautious 
taxonomists have often referred specimens to Genus sp. (which, of course, 
is problematic for monotypic genera), but which adds a layer of hedging 
that you propose to eliminate. Without knowing your particular set of 
conventions, the person to whom you are speaking can only unequivocally 
consider one specimen to belong to the group you are discussing whether you 
use a species name (the type of the species) or a genus name (the type of 
the type species). By using a genus name, you greatly expand the list of 
possible specimens you are including, and therefore the ambiguity of your 
statements.

I don't meant to be patronizing, but I can't help but suspect that your 
interest in abandoning species epithets comes from a dino-centric 
perspective. Dino workers love to coin new genera. In some other areas of 
paleontology, and generally in neontology, monospecific genera are the 
exception. But take, say, Romer's Osteology of the Reptiles. I find this 
work nearly useless for systematics, because Romer generalizes at the genus 
level. I can't be certain that species but the type actually agrees with 
his descriptions (and I fear that sometimes the type doesn't as well). Had 
he given species names, and/ or discussed the context in which he used 
genus names, this ambiguity would have diminished remarkably, and his work 
would be much mroe useful today.

Wagner


Using just a higher taxon name adds

At 11:41 AM 10/15/04, you wrote:
> Quoting "Jonathan R. Wagner" <jonathan.r.wagner@mail.utexas.edu>:
>
> > >The third possibility is a two genus solution a la Wright and Lull, with
> > >Edmontosaurus regalis and Anatosaurus annectens and Anatosaurus copei
> > >(assuming the phylogeny is indeed regalis + (annectens + copei)).
> >
> > Or, for those of us who hate genera, nested clades: Edmontosaurus including
> > regalis and Anatosaurus, Anatosaurus including annectens and copei.
> > Personally, I think this is a little much, but that's because I hate 
> genera.
>
> Or just call them Edmontosaurus, Anatosaurus, and Anatotitan.  Screw the 
> species
> names.
>
> Nick Pharris
> Ph.D. Candidate
> Department of Linguistics
> University of Michigan