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Re: Classification: A Definition
----- Original Message -----
From: "Botterweg, Rrp" <firstname.lastname@example.org>
Sent: Monday, May 14, 2007 10:47 AM
David Marjanovic wrote:
"It's not really an alternative. Phylogenetics and PN together make
classification completely superfluous; it just drops out of the equation;
neither it nor any alternative is needed. "How should I translate a tree
into a classification" turns out to be a wrong question, like Lowell &
Dingus's famous "why did Napoleon cross the Mississippi"."
Unless I misunderstand something here (and would love to be informed), I
tend to say that this goes a bit too far, at least as far as the lower
taxonomic levels are concerned (family and particularly below), for a very
practical reason: overview.
I still don't understand what you mean. The names will stay, only the ranks
will stop being mandatory. You will be allowed to actually use
Euhadrosauria, even though it has no rank and even though it is part of a
traditional family (Hadrosauridae) but includes two traditional subfamilies
(Hadrosaurinae and Lambeosaurinae). Instead of "subfamily Hadrosaurinae",
you will be allowed to just say "Hadrosaurinae". That's what I mean.
Since phylogenetics/cladistics show relative distances between
The term "distance" is used for branch lengths
it might become rather impractical when dealing with large numbers of taxa
(genera, species), one tends to loose overview (such as the large numbers
of Amphibian species I am contributing to at AmphibiaWeb and 'Amphibian
Species of the World', on-line version, at the AMNH), but I admit I am
approaching this from a database angle.
You know how to find a file on a computer: files are grouped in folders, and
folders again in folders. (That's even often called a "tree".) There are no
restrictions on how long such a chain of nested folders can be, the folders
don't have ranks (nobody would say that C:\WINDOWS\system32 is or is not
somehow at the same rank as C:\Program files\IrfanView), and there are no
rules that some folders may not directly contain files but only folders.
This is what applied phylogenetic nomenclature looks like, and I have
mentioned a few important differences to traditional classification.
Or have a look at how languages are recognized as belonging to clades the
names of which lack ranks. There have been a couple of attempts to introduce
ranks there, but they have all been so unsuccessful that Wikipedia doesn't
even mention them. Compare, for example, the infoboxes of
http://en.wikipedia.org/wiki/Bambara_language on the one hand to that of
http://en.wikipedia.org/wiki/Mountain_zebra on the other. Which method do
you consider more useful? Which contains more information?