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Re: The Holy of Holies... Dinosauria II



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