Farewell to Species - reticulation
kinman at HOTMAIL.COM
Mon Feb 14 08:47:46 CST 2000
Curtis and Tom,
Unfortunately, packing all that information into "formal" ranks (and
new names to fill all those ranks), i.e. strictly cladistic classification,
eventually stretches the Linnaean System into uselessness and increasing
As this inevitability begins to manifest itself, cladists blame it on
the Linnaean System and begin to simply abandon ranks (which brings in a
whole new set of problems). Sort of like blaming the victim.
I concluded over 20 years ago that the only logical approach was to
keep the main Linnaean ranks, and to store cladistic (as well as eclectic)
information in an alpha-numeric code. Along with Kinman markers, I had a
system I have used ever since and find very useful.
With such a system now available, I cannot understand why cladists
would choose either of the two other options (abandoning phylogenetically
informative classifications in favor of cladograms, or running full speed
towards a cladistic cliff). In my opinion, strictly cladistic
"classification" will always fail in the long run, and in the process the
utility of cladistic "analysis" is being obscured.
That is why I ended my 1994 book stating my hopes that it would
"promote the positive attributes of cladistics at the same time it attempts
to eliminate the undesirable side effects of the unbridled use of this
valuable tool in classifications (and being a tool, cladistics should serve
us, not tie our hands)."
P.S. I am tempted to delve into the additional problems of regarding sister
groups as having objective reality (rather than just a useful Hennigian
methodogical assumption), but I guess that would open up a really messy can
>From: Curtis Clark So you are saying that the species rank is defined as
>being terminal: not a problem, I see your point, everything you say makes
>sense in that light. But the term species has another meaning (several,
>actually, if we get into
>BSC and such, but I'll focus on the one I like): the smallest group within
>which relationships are tokogenetic, but relationships with other species
>are phylogenetic. By this definition (or even by BSC), that first mammal
>was probably a species. It doesn't matter one whit how we rank it now, but
>when ancestral species are "still around" (in the tokogenetic continuity
>sense), it muddies the waters for them to become higher taxa when many of
>us are still (productively) using other species concepts.
>Ironically, all this is an additional argument for rankless classification,
>since we could have our species and diverge them, too.
>Curtis Clark http://www.csupomona.edu/~jcclark/
>Biological Sciences Department Voice: (909) 869-4062
>California State Polytechnic University
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