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Re: Distributions of morphological characters and more

----- Original Message -----
From: "Michael Mortimer" <mickey_mortimer111@msn.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 premaxillary
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.