Re: Thoughts on the biggest morphological bird analysis

[Tim Williams <twilliams_alpha@hotmail.com>]

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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