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RE: Sauropodz r kewl WAS silly ramble



Chiming in briefly. I'd reply instead to the comments of Anthony Docimo, but 
Mike's reply is here now, so I'll go with this. This is not intended to be a 
direct reply to Mike, but it does call out to something (or the manner) of what 
he wrote.

Mike Taylor wrote:

<Correct. For all *practical* purposes, Brachiosaurus is a terminal taxon. The 
moment you try to refer another species into that genus (e.g. "Brachiosaurus" 
brancai (Janensch 1914)) you are gambling your> name on a phylogenetic 
hypothesis, and begging to have it removed to a different genus (Paul 1988, 
Taylor 2009).>

  There is a persistent illusion involved in the nomenclature of ALL animals 
(not just dinosaurs) that are primarily investigated by paleontologists. This 
illusion does not necessarily exist in zoologists who investigate LIVING taxa, 
and is rather the reverse view. That is, that the "genus" is not only 
meaningful but often identical to that of the species. In this case, rather 
than the case of a tiered level of named taxa (generally beginning at the 
species), paleontologists generally anchor their nomenclature at the "genus" 
first, and specialize forms thereafter (naming new species, which is really 
what we end up arguing about when we talk about which "genus" *brancai* belongs 
to).

  While the case of zoologists tend to be largely conflated with the use of 
Linnaean terminology, they usually explain and describe taxa through the form 
of specialized or subsets of these taxa: the white rhino, the eastern grey 
squirrel, the reticulated python, etc. They equate some of these qualifiers 
with "species" names or groups of species, or subspecies, but these tend not to 
actually refer to general morphologies. As such, biologists tend to refer to 
taxa using the species name, so *C. simum,* *S. carolinensis* and *P. 
reticulatus*, respectively. Species names, especially species groups by species 
name referents, are more common in extant and Recent zoological studies and 
descriptions.

  Paleontologists, perhaps as an artefact of their perspective born from 
limited resources on variation and such, tend to look at broader categories of 
groups, and tend specialize from there when data is suggestive. This results in 
a heavy dose of referring to taxa through the less specific, or "genus," 
category. Thus, *Ceratotherium,* *Sciurus* and *Python* (respectively). This 
seems to influence the ability of paleontologists to willingly allow multiple 
species in a "genus," but there are other attitudes and perspectives that 
differentiate the results of this into the "lumper" and "splitter" mentalities.

  The real takeaway to this is that perennial and oft-ignored element of 
taxonomy, the nature and/or existence of the "genus" and "species." There is 
more of a trend to attempt to justify the actual existence of "genera" through 
active ignorance by paleontologists of species diversity in common with 
zoological taxonomy, which has resulted in no end to use debating the topic of 
the reliability or justification of species referral -- and especially erection 
of "genera" -- with or without phylogenetic analysis. This is no more apparent 
than the argument that "genera" can be coined or lumped with a single 
phylogenetic analysis, that species can be moved around by the same, or that 
any of this is realistically meaningful in the first place.

  All of it could actually be avoided by doing away with the premise that the 
"genus" exists. It doesn't. What form we name a biological grouping, and how we 
related these groups to one another, is a different matter entirely, and the 
use of "genera" (and even the differing ways we consider "species") obscures 
and muddles this argument. I fault everyone in this argument for continuing to 
use this confusing and frankly unscientfic framework to have this discussion.

Headden out ... and Cheers,

  Jaime A. Headden
  The Bite Stuff (site v2)
  http://qilong.wordpress.com/

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


"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
Backs)


----------------------------------------
> Date: Tue, 17 Apr 2012 09:36:34 +0100
> From: mike@indexdata.com
> To: keenir@hotmail.com
> CC: david.marjanovic@gmx.at; dinosaur@usc.edu
> Subject: Re: Sauropodz r kewl WAS silly ramble
>
> On 17 April 2012 09:13, Anthony Docimo <keenir@hotmail.com> wrote:
> >> Date: Tue, 17 Apr 2012 08:15:15 +0100
> >> From: mike@indexdata.com
> >> To: keenir@hotmail.com
> >> CC: david.marjanovic@gmx.at; dinosaur@usc.edu
> >> Subject: Re: Sauropodz r kewl WAS silly ramble
> >
> >
> >> >> > (Well, that or dinosaur paleontologists could stop putting every new
> >> >> > species in its own genus, already!)
> >> >>
> >> >> I think they should (at least for the most part) stop pretending to
> >> >> recognize species at all.
> >> >
> >> > but then wouldn't the Genus be the new LITUs?
> >>
> >> Yes. But with the crucial advantage that the name itself no longer
> >> depends on a phylogenetic hypothesis. When I name a new dinosaur as
> >> (say)_a species of Brachiosaurus, if it then turns out that
> >> Cedarosaurus weiskopfae clades closer to Brachiosaurus altithorax
> >> proper than to my new animal, then either I have to move mine to a new
> >> genus, or move the species weiskopfae into Brachiosaurus.
> >
> > Ah, okay; see, here is where my confusion may have arisen in this case:  
> > when I hear "let's get rid of the 'Species' rank"...what my mind interprets 
> > that as is "let there be nothing below Genus".
>
> Yes, exactly. Among dinosaurs, there really IS nothing below genus.
> (There are a few exceptions: a few dinosaur genera that contain
> multiple species. In pretty much every case, there are arguments
> about those referrals.)
>
> > ...which leads to, in your example, the question of "how do you move 
> > weiskopfae into Brachiosaurus, when there is nothing below Brachiosaurus?"
>
> >> Either way,
> >> an actual NAME changes, which is never good for any meaningful
> >> stability. Much better just to give each species its own genus name
> >> and let them shuffle around the tree as they will.
> >
> > Sounds like a paradise for splitters.  (or a paradise of what lumpers fear 
> > from splitters)
>
> So?
>
> Really. What *specifically* would be bad about this?
>
> Linnaeus invented the binomial convention while thinking about extant
> diversity. That differs hugely from Mesozoic diversity in two ways.
> First, there is appallingly more of it, so that coming up with a
> unique uninomial for each species is just impractical, whereas for all
> the rapid growth in named dinosaur genera, we're still only around the
> 1000 mark. Second, you can get multiple complete specimens of extant
> species, so you can make much firmer conclusions about phylogeny
> (which isn't to say that that neontologists don't make mistakes). But
> when you're dealing with 150-million-year-old species that are based
> on very partial, badly crushed and broken specimens (usually only
> one), then EVERY phylogenetic hypothesis is really a wild guess, and
> almost certain to be contradicted somewhere down the line. In that
> situation, it's crazy to tie terminal-taxon nomenclature to phylogeny.
>
> Put it this way: if Linnaean taxonomy didn't exist and we were
> inventing a nomenclatural system from scratch for Mesozoic dinosaurs,
> we would NEVER come up with the idea of binomials.
>
> > Though, if there are no species ranks, wouldn't that create even more 
> > arguments about if the new find is a Brachiosaurus? (before the elimination 
> > of Species, we might have said "the new find is a variant of Brachiosaurus 
> > altithorax")...I'm particularly fearing what the ceratopsian debates will 
> > become with no subdivisions below Torosaurus, Triceratops, etc.
>
> Why? What exactly do you fear? The arguments would be arguments
> about *science* rather than about taxonomy. That's a better use of
> all our time.
>
> -- Mike.