Some further "obscure taxonomic quibbles".
>In the taxonomic hierarchy, subspecies is a higher level than variety,
>however these two categories have NOT been used consistently by
>botanists. For practical purposes you can usually consider var. to be
>synonomous to ssp. although the two should not be used
>interchangeably. Both descriptors refer to morphological variation
>usually involving several charactors and having a geographical basis.
There is no standard definition of subsp., var., and f., but still they
should *not* be considered synonymous. At least these ranks are different
in inclusivity: subspp. may include several vars. or ff., vars. may include
several ff., but not the other way round.
In order to fill these cathegories with some meaning, one (the one I am
folowing) concept is to base subspecific distinction on geographic
disjunction (as John L. has pointed out already), i.e. subspp. are taxa "on
the way to" allopatric speciation (allopatric taxa). Vars. are sympatric
taxa in this concept differring in ecological respects (preference for
alkaline vs. acid soil, highland vs. lowland populations, different
pollinators, etc.).
However, it is still a matter of +/- subjective decision which differences
should be *sufficient* for distinction as subspp. and vars..
>The category form is used to describe variation which does not have a
>geographical basis, and which is usually sporadic in a population.(...)
>>However, the use of
>form is often discouraged, except for extremely unusual variants, or forms
>which occur in economically important plant groups. As Barry has pointed
>out, variation can be described in other ways than formal designation of
>forms.
Yes. I also think ff. are not significant in terms of taxonomic distinction
(which should IMHO reflect solely results or trends of speciation, i.e.
taxa being species or parts thereof which might have the potential to
become species eventually).
>(I am not sure about the creation of autonyms when forms are designated).
It is (formally) the same as with subspp. and vars..
The argument among splitters, lumpers, infraspecialists &al. is fed by the
delicate nature of the problem considered, i.e. the (human=futile &
subjective) attempt to draw clear cut borderlines in a more or less
continuous spectrum. Quite naturally, nomenclature can only be as stable as
the objects named. Some species are not exceedingly stable. It is these
which frequently abound with rejected, recombined, and revised synonyms. No
rules or methods can change this situation. It is rather the task of the
scientist to collect the existing opinions of his/her colleagues, to add
own knowledge and results, and to decide ("H.sapiens"...) which concept to
follow. It cannot be the goal of taxonomy (or science in general) to
generate a conclusive world formula, but rather to propose and modify
theories which eventually converge with reality by ongoing discussion.
Kind regards
Jan