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Re: Classification: A Definition
> On Wed, May 16, 2007 at 12:21:59PM +0100, Mike Taylor scripsit:
> > Botterweg, Ronald (R.B.) writes:
> [snip -- this is Mike, not Ronald]
> > And that is why I cordially disagree with David Marjanovic's claim
> > that PN makes taxonomy obsolete. We'll always need alpha taxonomy.
> I don't see what we get from families or orders that we can't get from
> clade names;
No, no, _alpha_ taxonomy, the naming of species and genera. Those we
will never get rid of. Above that level I am broadly in agreement
that the ranks do more harm than good -- which should not particularly
suprising given that most of what little there is of my publishing
record is on rank-free phylogenetic nomenclature.
> "Maniraptora" the clade is a perfectly good chapter heading, index
> entry, and term of reference, even if it's "Maniraptora <cited
> definer> <date>" rather than "Family Maniraptora", isn't it?
Yes. No-one to disagree with here, move along.
> > > For example, besides the two mentioned amphibia websites, large
> > > standard works (just a few that I happen to know and use) such as
> > > Wilson & Reeder Mammal Species of the World and Walker's Mammals of
> > > the World, would become very impractical, loosing overview without
> > > classification in orders, families, etc.
> > A courageous approach would be to do away with chapters completely,
> > and just order the entries according to a pre-order depth-first
> > traversal of the hypothesised phylogeny. But here I am using the word
> > "courageous" in the Sir Humphrey Appleby sense :-)
> Oh, piff -- I may not know much about dinosaurs, relatively speaking,
> but I know lots about structuring information. You can perfectly well
> pick a phylogentic hypothesis, pick the resulting representative tree,
> pick a sibling-level slice through the children of that tree some number
> of levels down from the root, and use those clade names as your chapter
> headings if you want to. It's actually *easier* from an information
> design point of view to structure a book that way than by arbitrary
> buckets labelled families.
The buckets would still be arbitrary, dependent to a ludicrously
unstable degree on the taxon selection. Throw another basal sauropod
in there and Neosauropoda is suddenly eleven nodes down from the root
instead of ten, and the hypothetical chapter-headings scheme in which
we use the level-ten nodes suddenly leaves with no Neosauropoda
chapter but with an unexciting
Node-uniting-Lourinhasaurus-with-Neosauroda chapter. Picking an
arbitrary level is also a horrible way to go -- which is why
_Dinosauria_ 2nd ed. does what everyone sane would have expected it
to do, and uses chapter headings based on the "well-known" clades.
... but as soon as you've nominated some clades as more well-known
than others, you've done taxonomy. We may as well admit it to
ourselves. It's certainly true that PN requires us to do much _less_
taxonomy than previously, but it doesn't eliminate it.
> > I truly don't know. It certainly is awfully hard to resist them
> > tempatation to write things like "... and so representatives of at
> > least four sauropod families are known from the Wealden". And
> > changing that to "at least four clades" only makes things worse.
> "Representatives of the sauropod clades <clade name> <cited
> definer> <date>, .... are known from the Wealden" strikes me as
> much more useful. Even the angiosperm worker knows what they've
> got and where to look up the definitions.
That works. It gets cumbersome pretty quickly, though.
/o ) \/ Mike Taylor <email@example.com> http://www.miketaylor.org.uk
)_v__/\ "I never comment on referees and I'm not going to break the habit
of a lifetime for that prat" -- Ron Atkinson, after WBA's UEFA
Cup defeat to Red Star Belgrade.