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Re: Viva Neornithine Birds!

--- David Marjanovic <david.marjanovic@gmx.at>

> >>That is yet another question. Molecular dating
> argues against the idea 
> >>that
> >>*Polarornis* and *Neogaeornis* were loons --
> >
> > Does it?  Ericson et al. (2004) seems to at first
> glance, until you 
> > realize
> > they only included Tertiary taxa to calibrate
> their divergence dates.  If
> > you ignore the Cretaceous neornithine fossils, of
> course the divergence
> > dates will come out as too late to incorporate
> them.
> No, no, I'm talking about van Tuinen & Hedges
> (2004): when *Polarornis* and 
> *Neogaeornis* are assumed to be either crown gaviids
> or stem gaviiforms and 
> as such used to calibrate molecular dating, the
> results are patently absurd.
> http://dml.cmnh.org/2004Dec/msg00048.html (scroll
> down to "Calibration with 
> Cretaceous loons"). 

FWIW, the Waimanu paper *strongly* indicates that
something like that should have existed then and
there, and that it was not loons, but very likely

And basalmost loons still seem to make good candidates
for C/P survival. Though they would probably be more
like a neoavian version of _Gansus_.


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