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Re: Multiple losses of flight in ratites?



> What may be an interesting extension of this is the possible
> lines of evidence leading to the differential pectoral and
> brachial anatomies of the various lineages.

As far as brachia are retained, yes ;-)

Might be worthwhile to do a morph analysis of that part of the skeleton, 
including skull sans beak and the upper vertebrate column (if there is anything 
of value in the latter). Include fossil paleognaths & basal Neornithes incertae 
sedis, Ichthyonis, cracid, Vegavis make a nice outgroup here (+ time 
constraints)

The leg and pelvic skeleton probably give the strongest bogus signal. It could 
be strong enough to "clade" ostriches + rheas, tinamous + lithornithids,  moa + 
elephantbirds. Instead of legs and pelvis characters, it would probably be more 
interesting to use e.g. more head charactesr, to see what hapens to emus, moa, 
cassowaries.

Kiwis will be a problem - too uniquely autapomorphic; they are hard to get to 
ally with anything (as they must have been, else where are the indications 
paleognaths evolved in NZ?). It might be tried if leaving them out makes the 
topology more robust.

What might also be tried here is: which possible clades are *rejected* by the 
most analyses or with the highest certainty (lowest support)? Because as far as 
the last 2 decades or so show, about every cladistic analysis of paleognaths 
yields one or more "clades" which make all alarm bells ring. Again, kiwis are 
very much unlike any other paleognath. But it might resolve the tinamou thing.

Otherwise, I have not read the paper yet but the excerpts look promising. It's 
certainly not "mainstream" whatever that is here, but they seem to make a good 
case and I cannot out of hand contradict it. Far from it indeed - if the 
fossils fit, this proposal seems as good as any and better than many.

It does not rule out a dispersal that was essentially vicariant by foot. None 
of the known flying paleognaths looks in any way like a long-distance migrant 
or something that could comfortably cross oceans even by accident. So even if 
they could have flown, it is not unlikely that walking was actually faster for 
Gondwanan dispersal.

Regards,

Eike

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