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Re: A plea to theropod workers- Code the Taxa in Your Analyses



 I've often complained about workers leaving out conflicting
 characters (e.g. Sereno, 1999)

This is so pervasive that Sereno himself gave a talk on it here two months ago and evidently has a paper on it in the works.

 recently I've noticed a more insidious problem.  Somebody will
 include a character and plenty of taxa, but then only code the
 character for a few of those taxa.

Wow. I haven't seen that in Paleozoic tetrapod phylogeny, where the other two problems are common!

 It just breeds complacency and a false impression of consensus,
 leaving us unlikely to ever find unexpected relation!
 ships fro t
 papers which are guilty of this problem are the Smith et al. (2007)
 Cryolophosaurus analysis, the Xu et al. (2009) Limusaurus analysis
 and the Choiniere et al. (2010) Haplocheirus analysis.

Got chopped.

 I'll repeat a point that needs to be made depressingly often- the
 function of cladistic analysis (and science in general) is to
 question, not to confirm.  It does no good to only feed PAUP the data
 which supports your idea.  You might as well not even waste the time,
 and just list the characters instead.

...which is what was done a lot in the 1980s and early 1990s: people presented a tree (a stick-figure tree, so it looked like a cladogram and was often even called one!) and a list of autapomorphies for each node, but there was no matrix and thus no information on how the listed characters were distributed further away from the nodes in question and very little information on which characters contradicted the presented tree. It's pretty frustrating to read such papers (such as Andrew Milner 1988 and 1993 on tetrapod phylogeny and lissamphibian origins or Benton 1985 on diapsid phylogeny).