"Cetiformes" and Dinosauriformes

["Ken Kinman" <kinman@hotmail.com>]

Nick and Zoe,
    Actually I should have put the name in quotation marks: "Cetiformes", 
since this name has never been proposed in the literature AFAIK.
    Even though I am more of a lumper than a splitter (in general), in this 
case, I felt that there was a definite possibility that whales could be 
polyphyletic (diphyletic).  Therefore in my 1994 book, I split them into 
three separate Orders: Archaeocetiformes (7 families), Odontocetiformes (17 
families), and Mysticetiformes (6 families).   I coded them as a clade, and 
if its holophyly can be clearly demonstrated, I would have no problem 
combining them into one Order "Cetiformes".  I don't see any reason to use 
the spelling "Cetaciformes" (which I assume is based on a plural form 
"cetacea" rather than the singular "cetus").  If there is a linguistic 
problem here, I would like to hear it (but if it is just a phylocode thing, 
I am not going to give it much weight).
     I coded Order Mesonychiformes as sister group to the whale clade, but 
recent evidence clearly shows that many (if not all) whales are closer to 
Order Artiodactyliformes.  Therefore, as I said, I plan to move 
Mesonychiformes up to show them as sister group to an artiodactyl-whale 
clade (cetartiodactyls) and still assume that whales are probably 
holophyletic.
    However, if whales do prove to be diphyletic, I will then move up any 
of the three whale Orders up next to Mesonychiformes if need be, and would 
of course abandon any contingency plans to formally recognize a 
"Cetiformes".  I don't think the non-holophyly possibility has been 
thoroughly tested by morphologists or the molecularists.
     This is exactly the same approach that I took with the dinosaurs, with 
Order Saurischiformes and Order Ornithischiformes coded as a "dinosaur" 
clade.  If and when I am satisfied that there is a set of significant 
dinosaur "synapomorphies", I will combine them into a single Order 
Dinosauriformes, which will probably closely match the content of the 
cladistically defined Dinosauriformes.   I prefer to "lump", but on the 
other hand I only formally recognize (with names) the most strongly 
supported clades.
    I am still studying some of the more "significant" dinosaur 
synapomorphies that have been suggested:  astragalar ascending process, 
cervical epipophyses, large deltopectoral crest, some form of partially open 
acetabulum, elongate vomers, and perhaps even the reduced posttemporal 
openings (although the latter has arisen independently in a lot of other 
groups).  Thus the latter one may end up off of my list (along with "three 
or more sacral vertebrae", twist thumb, and postfrontal absent).  The "three 
sacral vertebrae" thing was what really got me into dinosaur origins, and as 
far as I'm concerned, Galton has laid that one to rest.  You can call that 
"synapomorphy" anything you want (bad, insignificant, weak, rejected, or 
whatever), it's definitely off my list, and I am concentrating on those that 
seem to be potentially better (more significant, stronger, more worthwhile, 
etc.).  If that is "subjective" weighting, so be it.  That's the approach 
that I personally find most valuable (see Mayr and Ashlock's 1991 book for a 
discussion of discrimating between characters and what types should be given 
more weight).
              -------Ken Kinman
*******************************************
> From: NJPharris@aol.com
> To: <kinman@hotmail.com>, <dinosaur@usc.edu>
> Subject: Re: Whales, not whippos (Probably!!?)
> Date: Fri, 21 Sep 2001 14:57:40 EDT
>
> In a message dated Fri, 21 Sep 2001  1:44:04 PM Eastern Daylight Time, "Ken 
> Kinman" <kinman@hotmail.com> writes:
>
> >      This new information makes me even more determined to maintain a
> > separate Order Mesonychiformes, and (for the time being) coded as sister
> > group to a cetartiodactyl clade---- but with artiodactyls and whales 
> still
> > as separate orders from one another and the latter as exgroup of the 
> former:
> >
> >    14  Mesonychiformes
> >    15  Artiodactyliformes
> >    _a_ Cetiformes
>
> Shouldn't this last one be "Cetaciformes"?
>
> --Nick P.


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