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Re: Thoughts on the biggest morphological bird analysis
If we hold Livezey and Zusi's analysis to the same standards as huge
molecular analyses in regards to support (say 95% bootstrap liklihood)
That's too strict. Bootstrap is well known to produce too low support
values, just like how Bayesian posterior probabilities are generally too
high (they always tend to be 100 % even for rather obvious cases of
long-branch attraction -- Zhang et al. 2005 Systematic Biology).
That's another case of convergence, I bet. Adding *Palaeotis* and
*Diogenornis* should be interesting.
Isn't that Anatoidea?
It goes without saying that the ICZN mandates the deletion of the hyphen.
Not that I care... well, instead of "avoiding the controversy", Livezey and
Zusi set themselves at odds with both the ICZN and the PhyloCode...
What this says to me is that the relationships of major neoavian taxa may
forever beyond morphological resolution if only recent taxa are included.
You could well be right.
In Asher et al. (2003), two of the best supported clades are bats plus
flying lemurs, and pangolins plus anteaters.
I hope that's pangolins plus Xenarthra as a whole!
(e.g. Paton and Baker, 2006; 12902 characters)
Is that the mitochondrial genome?
I have to agree with David regarding Livezey and Zusi's fear of missing
data. There's no reason Dinornithiformes and Aepyornthiformes should be
excluded when we have complete skeletons.
Actually... as described on pages 9 and 10...
"Two subfossil taxa -- Aepyornithiformes and Dinornithiformes -- for which
character states were only marginally recovered, were excluded for the
primary global search, and provisionally placed by means of two different
protocols. This measure was taken because simple analysis of these
imperfectly known, broadly similar, large ratites led to an apparently
artefactual couplet -- 'long-branch' distortions exacerbated by missing data
(Wiens, 2005) -- as sister-group of other ratites exclusive of Apterygidae.
First, each was analysed in the absence of the other in a global,
unconstrained analysis. Second, each was separately placed by means of
heuristic searches in which the primary tree was used as a backbone
constraint. The Dinornithiformes were scored as two families (Dinornithidae
and Emeidae) as approximated by Cracraft (1976a, b) and Worthy and Holdaway
(2002) during character analyses, but analysed as a single, merged taxon in
light of their virtually identical scores. Accordingly, the 'trimmed-merged'
data matrix provided in digital form by Livezey & Zusi (2006) comprised 150
ingroup taxa and 35 outgroups."
But they kept *Rahonavis* in? And accepted at face value the sister-group
relationship of ostrich and rhea, two other "broadly similar, large
Fossils are the morphologist's only hope
at combating such detailed convergence.
We know how Mayr will spend the rest of this year... :-)