2000 years of stasis
Stuart G. Poss
Stuart.Poss at USM.EDU
Fri Feb 4 17:11:52 CST 2000
My apologies for the incomplete previous post.
Perhaps much of the difficulty arises from the fact that cladistics does not
have explicit methods for assessing intraspecfic variation. The
discontinuities that are defined are those perceived by the investigator and
are of a qualitative nature and often do not well reflect a measured assessment
of variation across "like" features through all or a comparable part of
different life history stages. There is a grey area between the process of
identification of character state and subsequent analysis that Henig did not
directly address, or at lest not at the level of detail that would be typically
expected say in the context of assessing variation in polyploid genes in an
analysis of molecular variation or in an analysis of the point homologies among
selected landmark points in an analysis of morphometric variation. Without the
ability to assess the significance of intraspecific variability, it can be
difficult to assess the significance of transformations among character states
for a given cladistic character.
Thomas DiBenedetto wrote:
But this seems to fly in the face of the fact that it has been cladists who
have been in the
> forefront of the "diagnose vs. define" debates, and very much on the side of
> "diagnoses"! How on earth can cladistics be seen as essentialistic?
> I am also puzzeled by the remark "...I am looking at morphological
> discontinuities in a limited part of the world, and putting morphologically
> similar things into groups within groups.
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