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Re: Platecarpus tympaniticus - how to analyze a nomen dubium
-pops out of the shadows-
Ive been casually watching this thread...
Given that Ceratops montanus is one of very few, MT Judith River
Formation dinosaurs that have brow horns, I would imagine there would
be less discussion if there was a parietal to go along with the horn
1. What are or were the nomenclature rules for naming Ceratops and
Ceratopsia for Marsh, 1890? What are the differences in the ICZN
naming rules, then as compared to now, even with the over zealous
cladists running around? :) Wouldnt Ceratopsia still maintain priority
with the new rules because it was published first?
2. How would Sereno's 1986 Cerapoda fit into this.
3. As almost all ceratopsian dinosaurs have some sort of "ceratops"
in there name and being distinctly "horned" dinosaurs over any other
current species, whose names and family go back 110 years. Are one of
the few well known and recognized family groups to the general
public, how or and or why would this affect the naming and
nomenclature or clade rankings, if any or even why bring it up?
4. Even though "ranks (phylum, class, order, etc) have no intrinsic
value" then why bother with looking at the family names and
cladisitical analysis along with the phylogenetic code? As we know it
basically shows how everything is generally related over time, pending
on your selected characters and analysis.
On Tue, Sep 21, 2010 at 7:46 PM, Tim Williams <email@example.com> wrote:
> Anthony Docimo <firstname.lastname@example.org> wrote:
>> > *Ceratops*: has anyone even looked at the material in
>> > the last couple of decades?
>> Wait....if nobody's looked at the material, what has this
>> discussion been running on? (theory and ideals?)
> Don't panic Anthony. Penkalski and Dodson (1999) provide a fairly detailed
> description of the _Ceratops montanus_ type material. So does Ryan (2007).
> Both studies regard the _Ceratops montanus_ material as non-diagnostic at
> the genus or species level, and therefore the name _Ceratops montanus_ is a
> nomen dubium.
> I'm not actually endorsing the view that _Ceratops montanus_ is a nomen
> dubium (though I suspect it is). My argument is that given the meager
> remains, _Ceratops montanus_ is a poor choice to name a family after. Both
> the ICZN Code and PhyloCode agree that the family Ceratopsidae must include
> _Ceratops montanus_. Thus, Ceratopsidae must be defined such that it
> includes _Ceratops montanus_ as a specifier. But because _Ceratops montanus_
> is unlikely to contribute anything meaningful to a phylogenetic analysis,
> _Ceratops montanus_ is unlikely to be used to anchor any clade (including
> Ceratopsidae). Ergo, _Ceratops_ should NOT give its name to any family-level
> clades (e.g., Ceratopsidae, Ceratopsinae, Ceratopsoidea).
>> Except none of us are precognitive - we don't know
>> that better species will be found. (we hope they will,
>> but its not a guarantee)
> Mike Taylor answered this better than I ever could, but it's worth
> emphasizing the point that suprageneric taxa should not be erected for a
> single genus. This used to be common practice, but it's totally unnecessary,
> and frequently unhelpful.
>> okay, let's say that, twenty years from now, I discover a
>> dinosaur that is as related to other Archosaurs as the
>> Pangolins are to other Mammalia.
> This assumes that ranks (phylum, class, order, etc) have some intrinsic
> quantitative value. But they don't, and never have.
> Consider this: All those many bird "orders" (Struthioniformes, Falconiforme
> vialae. The Avialae is in turn a clade within the Maniraptora, which is a
> clade within the Theropoda, which is a clade within the Saurischia. Yet,
> Linnaean taxonomy lists Saurischia as an "order". Take-home message:
> Linnaean ranks are a world of pain.