[Taxacom] More evidence turtles are diapsids

[mivie at montana.edu]

Hypothesis: Examination of new characters will reveal potential
synapomorphies supporting the clade Turtles+Diapsids
Null Hypothesis: No such characters will be discovered.




> There is no 'test' of competing hypotheses here. Adding more effects to
> be explained by way of phylogeny simply means new hypotheses are
> inferred, replacing the old. No test has occurred, as no valid test
> implications stemming from the causal conditions stipulated by the
> hypothesis have been predicted.
>
> Kirk
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> J. Kirk Fitzhugh, Ph.D.
> Curator of Polychaetes
> Invertebrate Zoology Section
> Research & Collections Branch
> Natural History Museum of Los Angeles County
> 900 Exposition Blvd
> Los Angeles CA 90007
> Phone: 213-763-3233
> FAX: 213-746-2999
> e-mail: kfitzhug at nhm.org
> http://www.nhm.org/site/research-collections/polychaetous-annelids
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
> mivie at montana.edu wrote:
>> This turtle study is an excellent example of how the
>> molecular-morphological issue SHOULD work.  There is an established
>> morphology-based system, challenged by new data from molecules, setting
>> up
>> a test of competing hypotheses.  The test then causes new character
>> systems to be found and evaluated, leading to progress in the
>> whole-evidence understanding of the group.
>>
>> Why this is so seldom done in the great apes is a mystery.  The recent
>> Discovery special on Ardi was a perfect example of nonsense
>> pseudoscience
>> being presented to the  public about great ape origins.  In the program,
>> they kept saying they expected a human ancestor that was chimp-like,
>> showing a phylogram with chimps and humans having a most recent common
>> ancestor. Then, when they found something non-chimp like, they just drew
>> the same phylogram LONGER!  They never dealt with the idea of refutable
>> hypotheses, nor that fact that the common ancestor of humans and chimps
>> (at whatever level it existed) would not be expected to look like
>> either.
>> No wonder so much of the public has a misunderstanding of evolution if
>> we
>> teach them about it with such sensational and misleading stuff!
>>
>> Makes me understand more why this drivel drives John G over the edge.
>>
>> Mike Ivie
>>
>>
>>
>>
>>> Dear All,
>>>       A recent paper provides more evidence that turtles are well
>>> within
>>> the diapsid clade of reptiles (and therefore not true anapsids).  The
>>> citation and abstract are given below.
>>>      Note that they use the clade name "Pantestudines" in the title,
>>> which I believe should actually be spelled "Pan-Testudines".  If we are
>>> going to have to put up with all these new PhyloCode clade names, the
>>> "Pan-" names should be hyphenated to clearly distinguish them as such
>>> (and I believe that PhyloCode is going to mandate this).
>>>       --------Ken Kinman
>>> ------------------------------------------------------------
>>> An Archosaur-Like Laterosphenoid in Early Turtles (Reptilia:
>>> Pantestudines); by Bhullar and Bever, 2009.   Breviora, 518:1-11.
>>>
>>> Abstract
>>> Turtles are placed with increasing consistency by molecular
>>> phylogenetic
>>> studies within Diapsida as sister to Archosauria, but published gross
>>> morphology-based phylogenetic analyses do not recover this position.
>>> Here, we present a previously unrecognized unique morphological
>>> character offering support for this hypothesis: the presence in stem
>>> turtles of a laterosphenoid ossification identical to that in
>>> Archosauriformes. The laterosphenoid is a tripartite chondrocranial
>>> ossification, consisting of an ossified pila antotica, pila metoptica,
>>> and taenia medialis + planum supraseptale. It forms the anterior border
>>> of the exit for the trigeminal nerve (V) and partially encloses the
>>> exits for cranial nerves III, IV, and II. This ossification is unique
>>> to
>>> turtles and Archosauriformes within Vertebrata. It has been mistakenly
>>> dismissed as anatomically dissimilar in these two groups in the past,
>>> so
>>> we provide a complete description and detailed analysis of
>>> correspondence between turtles and Archosauriformes in each of its
>>> embryologically distinct components. A preliminary phylogenetic
>>> analysis
>>> suggests other potential synapomorphies of turtles and archosaurs,
>>> including a row or rows of mid-dorsal dermal ossifications.
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>>
>>> Taxacom Mailing List
>>> Taxacom at mailman.nhm.ku.edu
>>> http://mailman.nhm.ku.edu/mailman/listinfo/taxacom
>>>
>>> The Taxacom archive going back to 1992 may be searched with either of
>>> these methods:
>>>
>>> (1) http://taxacom.markmail.org
>>>
>>> Or (2) a Google search specified as:
>>> site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>>>
>>>
>>>
>>
>>
>> _______________________________________________
>>
>> Taxacom Mailing List
>> Taxacom at mailman.nhm.ku.edu
>> http://mailman.nhm.ku.edu/mailman/listinfo/taxacom
>>
>> The Taxacom archive going back to 1992 may be searched with either of
>> these methods:
>>
>> (1) http://taxacom.markmail.org
>>
>> Or (2) a Google search specified as:
>> site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>>
>>
>
> _______________________________________________
>
> Taxacom Mailing List
> Taxacom at mailman.nhm.ku.edu
> http://mailman.nhm.ku.edu/mailman/listinfo/taxacom
>
> The Taxacom archive going back to 1992 may be searched with either of
> these methods:
>
> (1) http://taxacom.markmail.org
>
> Or (2) a Google search specified as:
> site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>
>