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RE: a rose by any other name(was fish & dogs)



> From: philidor11 [mailto:philidor11@snet.net]
>
> <In the phylogenetic taxonomic system, the statement of ancestry is the
> algorithm used.>
>
> Definitional difference?  I'm using algorithm to mean a formalized process
> of decision-making unrelated to any specific example, as in a computer
> program.  Hence, the statement of ancestry is the result of the
> application
> of the algorithm.

By "algorithm" I meant "based on a formulaic statement in decision making."

So, we have an operational definition: Taxon Q = Taxon X, Taxon Y, and all
descendants of their most recent common ancestor.

We can then take Taxon A, and evaluate it.  If the data support it fitting
the description above, then Taxon A is a member of Taxon Q.  If the data do
not support this position, then Taxon A is not a member of Taxon !.

> Has no one, including you, ever tested to see what a new animal
> with a mouth
> full of stabbers, choppers, and grinders would do to your work?

If, by this, do you mean have I ever put a therapsid in my theropod matrix,
then the answer is "no".  You are welcome to do so.  I strongly suspect that
it will fall at the base of the tree, and be trying to get past the
outgroup...

However, we were talking before about taxonomic systems (methods of naming)
rather than phylogenetic reconstruction (methods of recovering the shape of
the tree of life).  These are different tasks, and if you choose to discuss
the latter (that is, phylogenetic reconstruction), then I would strongly
recommend changing the subject line!

Your remaining comments addressed questions of phylogenetic reconstruction
and character choice and expertise: matters that have been discussed on this
list a lot over the years.  If you do want to keep going with it, then
reply.

                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