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Re: Cetartiodactyla (was Re: Cladistic taxonomy (was Dietary factors))



Watch out, I'm griping again.

Ken Kinman (kinman@hotmail.com) wrote:

<That sounds very interesting.  I recognize a separate Order 
Mesonychiformes, so no matter how it and artiodactyls and
cetaceans are interrelated, I will be able to reflect it in my
classifications without having to change the contents of any of
these three orders.>

  Except that Mesonychia itself has been suggested to be
paraphyletic, in the same analyses that suggested they were not
ancestral to whales, and one other (sorry, I don't have the
paper, but I can dig up the cite....). Making up a
"Mesonychiformes" is irrelevant.

<Therefore retaining the traditional Artiodactyliformes (without
cetaceans) gives me more flexibility.  Whether it is
paraphyletic (gave rise to cetaceans) or holophyletic, I still
have the same stable groups (Orders) and can reflect all these
controversial interrelationships with an easily modified coding
sequence.>

  I'm afraid that there is nothing "traditional" about
Artiodactyliformes. It didn't exist in the traditionalist era we
consider "traditional" and is quite new. First semantic hurdle.
Next one... Artiodactyla will be monophyeletic even if Cetacea
is the sister group, as it does not rely on whales in its
compsosition. Phylogenetics suggest that whales are the sister
group to artiodactyls, not artiodactyls themselves. So questions
on monophyly, holophyly, or paraphyly are irrelevant unless you
want to support your statements with explicit information.

=====
Jaime A. Headden

  Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
  Where the Wind Comes Sweeping Down the Pampas!!!!

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