RE: Distributions of morphological characters and more

[Michael Mortimer <mickey_mortimer111@msn.com>]

Nick Gardner wrote-

> 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
> teeth?

I separate it in my coelurosaur analysis, and code taxa without premaxillary 
teeth as inapplicable for tooth number.  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 
character.

> Also, the supratemporal and infratemporal "bars" referred to
> separately by Sereno and You, what exactly are they? Is the
> supratemporal "bar" the postorbital-squamosal contact separating the
> laterotemporal fenestra and the supratemporal fenestra, and the
> infratemporal "bar" the jugal-quadratojugal contact that forms the
> ventral margin of the laterotemporal fenestra?

Yes.

> Additionally, You uses palatal characters describing "choanae" in his
> cladistic analysis, regretably, I've not been able to find out what
> these are. Can someone please point me to a figure or paper that
> adequately describes what part of the palate these are?

Choanae are internal nostrils.  Generally formed by the maxillae, vomer and 
palatines on the ventral surface of the snout.  Figure 22.3 in The 
Dinosauria: 2nd Ed. has a good view of them.

Mickey Mortimer