taxon promotion agreement

Ken Kinman kinman at HOTMAIL.COM
Mon Sep 27 14:01:54 CDT 1999

     I totally agree with you that the notion of taxa being promoted up the
ranking system gives an excellent perspective on evolutionary history.
However in our example, why raise sapiens to superspecies status and rename
earth mankind as Homo terrestris (or whatever).   Although sapiens doesn't
go extinct, it has disappear "as a species" in your classification.   Isn't
it more informative to retain the name H. sapiens for earth mankind (which
remains unchanged), and group both species of mankind in a sapiens species
group.  With your sister species approach, you can't tell if the mars
species evolved from the earth species or vice versa.  If budding is the
most common method of speciation, then a mother-daughter model is more
realistic, not to mention more useful and heuristic (this is point number
one in the final paragraph below).
     The Kinman System uses markers to document the "taxa being promoted up
the ranking system" (to use your phrasing).  For example, markers for
Metaphyta are placed at phylum level (after Chlorophyta), Class level (after
Charophycea), and ordinal level after Coleochaetales.  If someone thinks
they know the proper placement within Coleochaetales they could place a
marker at family level.
    I do not think we yet have enough data to know the proper placement that
far down the hierarchy (family level), so I code the {{Metaphyta}} marker as
sister group to Order Coleochaetales, thus showing that the family, genus,
and species of Metaphytan origins is still unknown.  The {{Metaphyta}}
markers higher in the hierarchy are coded paraphyletically, showing
Metaphyta as daughter group relative to Class Charophycea and Phylum
Chlorophyta.  This precisely shows Metaphyta being "promoted up the ranking
system" to Kingdom status.
     Cladists might complain that there would be too many markers.  However,
the number of ranks and names filling them (and the number of markers needed
as well) are minimized in the Kinman System by completely eliminating
intermediate categories  (subtaxa and supertaxa) by using a simple code (of
numbers and letters) showing proposed paraphyletic and cladistic
relationships.  Since this code is easily modified, new knowledge of
relationships is absorbed by this code, and the formal classification
remains very stable (unlike the hierarchical instability of cladistic
classifications, and rapid turnover of formal taxon names).  Subtaxa and
supertaxa can be formally recognized with the Kinman System if one really
wants to do so, but I find informal intermediate taxa and coding to be a
superior approach for a variety of reasons.
     So to summarize:  (1) Just because we don't know the exact species from
which higher level taxa evolved is no reason to reject the more realistic
and heuristic mother-daughter model;
and (2) on top of that, the price of strictly cladistic classification is
far too steep in terms of instability, reduced usefulness, and the lack of
anagenetic information.
                        -------Ken Kinman

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