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Re: "Ratite" polyphyly and paleognathous dromornithids
The authors find the tinamou position to be highly
> alignment-sensitive: sequences aligned according to a guide tree with
> a rhea-tinamou clade always resulted in a rhea-tinamou clade on the
> final tree. An emu-tinamou clade exclusive of rheas is less dependent
> on the guide tree topology and somewhat better supported, but the
> difference is not large and support measures are weak for both
How did they get those guide trees? (I'll have access to the paper in a
bit over a week.) I ask because ModelTest used to derive its guide tree
by neighbor-joining (and the Jukes/Cantor model), while yours truly &
Laurin (2007, Syst. Biol.) noticed that changing it to using the most
parsimonious guide tree yields different results... and, at least in the
example we used, the most parsimonious guide tree is much less horribly
implausible than the one found by neighbor-joining!
However, "ratite" monophyly is still supported by morphological
> Worthy TH, Scofield RP 2012 Twenty-first century advances in
> knowledge of the biology of moa (Aves: Dinornithiformes): a new
> morphological analysis and moa diagnoses revised. New Zealand J Zool
> 39(2): 87-153
> [...] Our phylogenetic analysis, based on 179 characters scored for
> 23 ingroup palaeognath taxa and three galloanseres as outgroups,
> resulted in several strongly supported relationships. Firstly, the
> Eocene palaeognath _Lithornis_ was either sister to remaining
> palaeognaths or had a weak affinity towards tinamous.
I know it's much easier said than done, but it would certainly be good
to add more lithornithids (their monophyly hasn't been tested!) and all
supposed Paleogene ratites (*Palaeotis*, *Eleutherornis*,
*Remiornis*...). The number of characters, and its ratio to the number
of taxa, is impressive.
Finally, a new paper on Australian fossil anhimids suggests that
> dromornithids are in fact paleognaths and Richard Owen was right
> after all. This contradicts many recent phylogenies that place
> dromornithids either in the stem group of Anseriformes (Murray &
> Vickers-Rich 2004) or the stem lineage of Galloanserae (Mayr 2011).
> Elżanowski A, Boles WE 2012 Australia's oldest Anseriform fossil: a
> quadrate from the Early Eocene Tingamarra Fauna. Palaeontol 55(4):
> A partial quadrate (essentially the otic part) [...] The quadrate
> morphology supports palaeognathous rather than recently claimed
> anhimid relationships of the Dromornithidae and identifies
> _Sylviornis_ as an anseriform rather than a galliform.
So... they used characters from the quadrate alone and ignored the
entire rest of the skeleton? ...Why would anyone do that?