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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.
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).