natural units in biogeography

[John Grehan]

Peter Hovenkamp's assertion that  "Natural classification" has no meaning
in biogeography represents a fundamental difference between our respective
views.

I agree that evolution of biogeographic histories is not the same thing
as evolution of organisms, but I do not see that more than one context
may be applied to evolution. Biota's have a history and a system of units
and classification that reflects that history is, to my understanding,
a natural classification. The units and classification tell us something about
the evolution of the real world.

>One alternative is, simply, not to expect biogeographic units to be
>non-arbitrary. Arbitrary units may be very useful in a variety of contexts
>- just as arbitrary classifications of biological objects are very useful
>in many situations (root vegetables vs. leaf vegetables, fruits vs. nuts,
>etc.).

As mentioned in another posting, usefulness or utility is an arbitrary and
artificial concept. In biology someone might find it useful to construct a
classification
in which bats and birds were grouped together. However useful, such a
grouping would have little to do with origin and history (the natural
character).

>Another is to accept my proposal not to use areas,

I would agree with this since my position is that all area units are
artificial.

but instead concentrate
>on their boundaries,

If the areas are artificats so to are their boundaries. Interestingly the
areas
of Wallace are biogeographic boundaries in panbiogeography.

John Grehan