[Taxacom] More evidence turtles are diapsids

[J. Kirk Fitzhugh]

These aren't deductive consequences, thus not test evidence. New 
characters can't be deduced from a phylogenetic hypothesis, since the 
hypothesis only states vague causal conditions pertaining to the 
characters from which the hypothesis was inferred. What is in need of 
being tested are those causal claims in the hypothesis, thus we have to 
find evidence that those occurred. This has been a long-standing 
misunderstanding in cladistics for far too long, and has been maintained 
in recent years by some authors publishing papers (especially in 
/Cladistics/), where the basic rules of deduction are blatantly violated.

Kirk

mivie at montana.edu wrote:
> 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