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RE: tiny-armed theropods



Tim and I have had this battle enough times that we're familiar with each 
others' opinions and talking points, but I couldn't pass this up...

> Briefly.... if _Troodon formosus_ becomes a nomen dubium, the name
> will be limited to the holotype: a single tooth. So what's the big
> deal? I'm glad you asked. If you carry out a phylogenetic analysis
> to determine the affinities of Troodontidae, you'll need to put
> _Troodon_ (= a single tooth) into the analysis. But if _Troodon_ is
> an invalid genus (i.e., not a valid operational taxonomic unit, or
> OTU) this would be pointless. Nevertheless, you'd have to stick
> _Troodon_ in the analysis just for bookkeeping reasons, to determine
> what is captured by _Troodon > Passer_.

By that reasoning, we'd have to include Passer in the analysis too, which I 
don't think you'd agree with.  Just as we can use our extra-analysis knowledge 
to be fairly certain Passer is closer to e.g. Anser, Yanornis, Confuciusornis 
etc. than to dromaeosaurids, troodontids, oviraptorosaurs, etc., we can use it 
to be fairly certain Troodon is closest to Zanabazar, Talos, Saurornithoides 
and such.  There's no need to include every definition-related taxon in an 
analysis.  Just think of how few analyses include Enantiornis, Therizinosaurus, 
Megalosaurus, Spinosaurus, etc..

As I've said before on the DML, people just cherry pick from the ICZN and make 
up their own rules, such as those involving nomina dubia.  They see their own 
subjective ideas of stability as overruling the ICZN, and if the majority 
follows them, what can we do but go along with the arbitrary flow?

Mickey Mortimer