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Re: Padian et al. 1999 (Was: New PaleoBios paper - diplodocoid phylogenetic taxonomy)

2005/10/4, Thomas R. Holtz, Jr. <tholtz@geol.umd.edu>:

> > Roberto Takata
> > But that was only because the taxonomists tried to not to push aside
> > evolutionary issues - well actually it was in the order of the day
> > since Darwin times.
> >
> Ummm... No.

Well, I think so. If taxonomist abandon the ideal of reflect
evolutionary relationships in their classification systems, that is,
give any objective meaning to their groups, a stability could be
achieved - before evolutionary systematics, linnean taxonomy merely
put beings in categories by their (mainly) morphological resemblances,
there is no hypothesis to test - just in a way that there is no
hypothesis to test in a library book order, it is a result of a priori
set of rules that must be applied. It keeps things in order.

> There was still plenty of disagreement in the basic taxonomy of pretty much 
> any group

Based in a evolutionary frame of thoughts. We could classify our
clothes by their colour - ok, could be some disagreement about if a
shirt is blue or purple, but not if the bluish aspect is a derived
charecter or a plesiomorphic one shared by costume pieces. If we
decide to sort out in shirts, trousers, socks and so on, we just have
to do it, and never a shirt will be among socks.

> But a phylogenetic system of taxonomy (including, but not limited to, that in 
> the
> PhyloCode) begins to give a smaller set of rationales than existed before.

Surely, I've just point out that the costs for those rationales is to
give up ever-lasting stability - a cheap price anyway. (In that sense
that I disagree with the claim that this or those definition is more
stable than other.)


Roberto Takata