generic oversplitting (heart of the problem)

Thomas DiBenedetto tdibenedetto at OCEANCONSERVANCY.ORG
Wed Jul 18 11:50:10 CDT 2001

-----Original Message-----
From: Ken Kinman [mailto:kinman at HOTMAIL.COM]
An Ashlockian approach, coupled with my simple convention for exgroups, is
almost certainly where we are going to end up eventually, so why put it off
and go through even more turmoil?

I have never found the argument, that one's own particular point of view is
certain to win out in the end, to be very compelling (even when I find
myself resorting to it). I see no reason whatsoever to think that this will
be the case in this particular instance. The reason is rather simple. The
cladist's disdain for paraphyly is fundamental to the cladistic point of
view. This perspective is based on the goal of structuring our scientific
classification in such a manner that it mirrors what we accept as the
historical pattern of taxic divergence. It accepts that the historical
process has yielded higher groups that divide to form lower groups, forming
a contiuous inter-nested hierarchy. The notion of taking (e.g.) one group of
the descendants of the ancestral reptile, and removing it from the natural
group formed by the all of the divergences of that ancestral reptile and its
descendants, is an absurdity within the cladistic perspective. It runs
directly counter to the fundamental goal of cladistics, which is to classify
in accordance with the historical pattern of lineage divergences.
I think that by now you should recognize that there is no compromise
available for this dispute. Either one accepts the principle that the
classifcation mirror the historical divergence pattern, or one doesn't. Your
appeal to a "reasonable compromise" rings hollow for it is in fact nothing
but an appeal for your own perspective. Eclectic classifications do not rule
out holophyletic groups, so your perpsective offers the virtues of tolerance
and inclusiveness. In fact though, it simply asks cladists to abandon their
fundamental principle and goal. That is not going to happen.
I suggest that any further argument on this point be focussed on the very
simple question that is truly at issue. Should the scientific classification
be aligned with our conclusions regarding how lineages have diverged, or
should our classification be only partly reflective of that pattern,
modified by other criterea as well. That has always been the real issue
between cladists and "darwinians". Paraphyly is a deriviative issue in this
dispute. Paraphyletic groups are an absurdity in the first perspective, and
they are probably a necessary feature of the second. It is a distraction to
argue about them when the real issue is even more fundamental.

Tom DiBenedetto

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