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Re: Whales, not whippos (Probably!!?)

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

Even if whales are not sister group to hippos in particular, their sister group could still be some subclade of artiodactyls. If they are sister group to *all* artiodactyls, that could be shown by simply recoding: 16 Cetiformes. Whether some mesonychiforms should be placed into Artiodactyliformes still remains to be seen.
Furthermore, it should be remembered that there are a large variety of whales (incl. dolphins and porpoises). Therefore, there could still be an outside chance that some of them are closer to hippos, while others are closer to some other group of artiodactyls (or mesonychiforms). The holophyly of Cetiformes is probable, but I don't take it for granted (at least not yet). Whippomorphs may be down, but not necessarily out (however much I personally dislike the name whippomorph). It should be kept in mind that a diphyletic Cetiformes could possibly explain some of the conflicts between the molecular and morphological data. Time will tell, but I suspect the debate is still far from over.
-------Ken Kinman
******************************************** 
From: "Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>
Reply-To: tholtz@geol.umd.edu
To: "dinosaur" <dinosaur@usc.edu>
Subject: Whales, not whippos, part II: Science
Date: Fri, 21 Sep 2001 09:06:58 -0400

Greetings,

As promised, the other new whale origin paper:
Gingerich, P.D., M. ul Haq, I.S. Zalmout, I.H. Khan & M.S. Malkani.  2001.
Origin of whales from early artiodactyls: hands and feet of Eocene
Protoectidae from Pakistan.  Science 293: 2239-2242.

Introduces the new genus & species _Artiocetius clavis_ and the new species
_Rodhocetus balochistanensis_. The skull of _Artiocetus_ is nearly complete
and is a thing of beauty! Postcrania of both taxa are well preserved. The
feet of _Rodhocetus_ look like an artiodactyl trying to be a sealion (which,
in a sense, is their interpretation of its ecology).

The net result seems to be that the fossil anatomy of basal whales pretty
much clinches their phylogenetic position: whales are closer to artiodactyls
than to any other living taxon AND are closer to artiodactyls than to the
majority of fossil mammals considered "mesonychids". Sure, more work needs
to be done, but it looks pretty strong.

Hope everyone is doing fine.  Take care,

              Thomas R. Holtz, Jr.
              Vertebrate Paleontologist
Department of Geology          Director, Earth, Life & Time Program
University of Maryland         College Park Scholars
              College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone: 301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661      Fax (CPS-ELT): 301-405-0796



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