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Re: Distributions of morphological characters and more
----- Original Message -----
From: "Michael Mortimer" <email@example.com>
Sent: Wednesday, August 17, 2005 7:51 PM
Additionally, I've the following character in my analysis:
Premaxillary tooth number: 0- four; 1- two; 2- three; 3- five; 4- six;
5- seven; 6- zero.
Should the sixth character state (zero premaxillary teeth) be
separated as "premaxillary teeth: 0-present; 1- absent" or is it fine
as a state within a character counting the number of premaxillary
I separate it in my coelurosaur analysis, and code taxa without
teeth as inapplicable for tooth number.
Fortunately TNT can cope with inapplicable characters...
That's only because I order the tooth number character, and toothlessness
seems to be able to evolve from both reducing tooth number (e.g.
oviraptorosaurs) and increasing it (e.g. ornithomimosaurs). So I don't
want to favor or punish either possibility.
But if you left it unordered, I don't see why you'd need the second
Why not make a stepmatrix. Order "two -- three -- four -- five -- six --
seven", and give the step from each of those to "zero" (or, alternatively,
just those from "two" and from "seven" to "zero" -- for example) a cost of
1. PAUP* has no problem with this, plus it spares you the problem of
inapplicability with which PAUP* can't cope.
I wouldn't completely unorder the character.