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Re: Philosophies for Character Ordering



----- Original Message -----
From: "Jaime A. Headden" <qilongia@yahoo.com>
Sent: Friday, May 21, 2004 8:27 PM

>   Say that two characters afford that two taxa are more similar to one
> another than any other relationship. A third character they share is known
> among more taxa. This third character is assumed to be a synapomorphy of
> the clade even if known in other taxa, because it diagnoses an ingroup,
> especially if the produced relationship has a sister taxon that lacks this
> condition.

Not "especially". _Only_ if the sistergroup and 2 or more successive
outgroups lack that condition can it be an unambiguous autapomorphy of the
clade in question.

> By this corollary, this third character should not be treated
> as if it were assumed to belong to any particular suite of transformation,
> in which case its broad usage becomes limited. It would then argue that
> that taxon also had the previous condition, and gives a character to a
> taxon for which it does not possess.

It argues that that taxon _had went through_ having the previous condition,
not that it still possesses it.

> In fact, the utility of multistates
> in this case is incredibly reduced unless the states are unordered,

?