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Re: Thoughts on the biggest morphological bird analysis



David Marjanovic wrote:

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).

Very true. I've seen molecular phylogenetic analyses produce 100% posterior probabilities for alternate topologies using different genes from the same taxa.


That's another case of convergence, I bet. Adding *Palaeotis* and *Diogenornis* should be interesting.

I'd like to see how an analysis deals with all those large flightless taxa - dromornithids, dinornithids, diatrymids, phorusrhacids, etc... How tempted is the analysis to pull all these taxa together based on shared traits that result from loss of flight and/or obligate terrestrial locomotion? I'm guessing the analysis won't be fooled.


|--Pygopodo-tubinares

It goes without saying that the ICZN mandates the deletion of the hyphen.

I'm not excusing this practice, but ornithology has a long history of hyphenated taxon names (e.g., Laro-Limicolae).


What this says to me is that the relationships of major neoavian taxa may be
forever beyond morphological resolution if only recent taxa are included.

You could well be right.

For sure. Imagine trying to reconstruct the phylogeny of nonavian dinosaurs based only on Maastrichtian taxa!


Fossils are the morphologist's only hope at combating such detailed convergence.

We know how Mayr will spend the rest of this year... :-)

The Messel birds could be very helpful, yes.

Cheers

Tim

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