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Re: Hypselospinus (Iguanodontia) from Early Cretaceous of Britain revised

Mickey Mortimer wrote:

< A term meaning "a taxon that cannot be referred to a valid species
because it cannot be distinguished from two or more species" is a
useful concept to have, so I think it's worth fighting for instead of
tossing it aside.>

That is a useful concept! But unfortunately it's not actually how the
term has been applied. So far, that term hasn't been defended by the
definition in print _at all_, which means getting people to look at an
effective philosophical argument for proper use of the term is going
to be hard. It's also not now "95%" of papers use it. They approximate
it by having a similar effect, but not function; throw a wrench and
the effect would differ, or they'd ad hoc it to make them conform. The
usage becomes about result, and not proper definition.

On Wed, Dec 3, 2014 at 2:58 AM, Mickey Mortimer
<mickey_mortimer111@msn.com> wrote:
> 95% of papers use nomen dubium the correct way, it's just exceptions like 
> Norman or that Rapator paper from a few years ago that get it wrong.  A term 
> meaning "a taxon that cannot be referred to a valid species because it cannot 
> be distinguished from two or more species" is a useful concept to have, so I 
> think it's worth fighting for instead of tossing it aside.  As for rank-based 
> nomenclature, I really wonder why Norman thought that could possibly be 
> useful to include.  It's like the workers who keep using paraphyletic taxa.  
> Why?  You're not going to be viewed positively by the future.  The taxonomic 
> zeitgeist is leaving you in the dust.
> Mickey Mortimer
> ----------------------------------------
>> Date: Wed, 3 Dec 2014 02:18:25 -0800
>> From: jaimeheadden@gmail.com
>> To: mickey_mortimer111@msn.com
>> CC: dinosaur@usc.edu
>> Subject: Re: Hypselospinus (Iguanodontia) from Early Cretaceous of Britain 
>> revised
>> The misuse of "nomen dubium" is systemic in paleontology. It's not
>> used consistently, as though multiple ideas are warring for rightness.
>> Some erroneously try to cite the ICZN for validation; others use it to
>> mean a non-diagnostic name-bearing type; yet others use it (more
>> prevalently) for a name you wish to sink into others. I covered this
>> more here: 
>> http://qilong.wordpress.com/2010/05/25/what-if-anything-is-a-nomen-dubium/
>> It doesn't matter what you work on. You'll tend to misuse the term if
>> you feel "right" and the other "wrong." Tossing the term aside as a
>> mere form of art will be preferable, as it is art stacked on art, a
>> frame to a picture without any supportive or protective component.
>> Imagine walking in a museum and while traveling through the galleries
>> you hear, "Oh, look how pretty this frame is, this must be an
>> important painting!" It is no less true of taxonomy, and the term of
>> art, "nomen dubium" runs afoul of the same errors that continue use of
>> rank-based nomenclature, or ranks themselves. It is particularly
>> notable that Norman misuses both.
>> On Wed, Dec 3, 2014 at 2:02 AM, Mickey Mortimer
>> <mickey_mortimer111@msn.com> wrote:
>>> Norman's nomenclature leaves much to be desired. He misuses 'nomen dubium' 
>>> as a term for junior synonyms, doesn't get the point of phylogenetic 
>>> nomenclature, and redefines most ornithopod clades in terrible ways that 
>>> are unnecessary and/or only function in his phylogeny. Hadrosauromorpha's a 
>>> good idea though. See my blog post at 
>>> http://theropoddatabase.blogspot.com/2014/12/normans-nomenclatures-notoriously.html
>>>  for the details.
>>> Mickey Mortimer
>>> ----------------------------------------
>>>> Date: Mon, 1 Dec 2014 09:01:15 -0800
>>>> From: bcreisler@gmail.com
>>>> To: dinosaur@usc.edu
>>>> Subject: Hypselospinus (Iguanodontia) from Early Cretaceous of Britain 
>>>> revised
>>>> Ben Creisler
>>>> bcreislerf@gmail.com
>>>> A new online paper:
>>>> David B. Norman FLS (2014)
>>>> On the history, osteology, and systematic position of the Wealden
>>>> (Hastings group) dinosaur Hypselospinus fittoni (Iguanodontia:
>>>> Styracosterna).
>>>> Zoological Journal of the Linnean Society (advance online publication)
>>>> DOI: 10.1111/zoj.12193
>>>> http://onlinelibrary.wiley.com/doi/10.1111/zoj.12193/abstract
>>>> The history of discovery and interpretation of several dinosaurs
>>>> collected from quarries near the town of Hastings during the latter
>>>> half of the 19th century is more complicated than it should be. Samuel
>>>> Husbands Beckles and Charles Dawson collected several large ornithopod
>>>> skeletons from this area, but just a few bones from these skeletons
>>>> were subsequently described and interpreted (principally) by Richard
>>>> Owen and Richard Lydekker. All these specimens merited recognition
>>>> because they had the potential to contribute to an on-going debate
>>>> about the anatomical structure and relationships of the iconic Wealden
>>>> dinosaur Iguanodon. Unfortunately, no detailed description of these
>>>> important skeletons was published in later years. Furthermore,
>>>> previously known associations of bones and even provenance
>>>> information, linked to the specimens that were gradually acquired by
>>>> the Natural History Museum, are unclear. Confusion may have arisen
>>>> because Richard Lydekker used the private collector Charles Dawson as
>>>> a voluntary curatorial assistant. This account documents the past work
>>>> on the osteology of material that can be attributed to Hypselospinus
>>>> fittoni. Nearly all such material is described here for the first
>>>> time, and every effort has been made to re-establish associations
>>>> between bones as well as provenance information. A skeletal
>>>> reconstruction of Hypselospinus is attempted on the basis of the
>>>> hypodigm. Most of the on-going confusion concerning the affinity of
>>>> this material with either Hy. fittoni or its sympatric contemporary
>>>> Barilium dawsoni has been resolved. Hypselospinus fittoni (Lydekker,
>>>> 1889) is rediagnosed on the basis of this new and relatively
>>>> comprehensive anatomical description, and this animal is compared with
>>>> known contemporary and closely related taxa. Some recently published
>>>> accounts claiming to be revisions of the taxonomy of Wealden
>>>> ‘iguanodonts’, including material belonging to the hypodigm of Hy.
>>>> fittoni, have failed to adhere to basic taxonomic principles and have
>>>> caused more confusion than was strictly necessary. The systematic
>>>> position of Hypselospinus is reassessed cladistically. The cladistic
>>>> analysis forms the basis for a revised hierarchical classification of
>>>> derived ornithopods. The consensus topology generated by the
>>>> systematic analysis has been used to explore the phylogenetic history
>>>> of these dinosaurs and create an internally consistent classificatory
>>>> hierarchy (phylogenetic definitions and Linnaean diagnoses are given
>>>> for critical positions in the topology). This analysis suggests that
>>>> there is a fundamental split amongst the more derived (clypeodontan)
>>>> ornithopod ornithischians into the clades Hypsilophodontia and
>>>> Iguanodontia. There is evidence for anatomical parallelism and
>>>> convergence (homoplasy) particularly between large-bodied
>>>> representatives of both clades. Hypselospinus is one of the earliest
>>>> known styracosternan iguanodontians and displays anatomical
>>>> characteristics that presage the evolution of the extraordinarily
>>>> abundant and diverse hadrosaurs of the latest Cretaceous
>>>> (Campanian−Maastrichtian). These observations cast fresh light on the
>>>> phylogeny, classification, diversity, and biology of derived
>>>> ornithopods. There is little doubt that Hy. fittoni could have been
>>>> understood far better more than a century ago. That this statement is
>>>> undoubtedly true is reflected in the century of doubt and confusion
>>>> that has surrounded this taxon and its original incarnation as
>>>> Iguanodon fittoni.
>> --
>> Jaime A. Headden
>> The Bite Stuff: http://qilong.wordpress.com/
>> "Innocent, unbiased observation is a myth" - P. B. Medawar (1969)

Jaime A. Headden
The Bite Stuff: http://qilong.wordpress.com/

"Innocent, unbiased observation is a myth" - P. B. Medawar (1969)