Re: SV: 55 million year old parrot found

[evelyn sobielski <koreke77@yahoo.de>]

> Riversleigh is early Miocene, isn't it? (It seems to
> oscillate in the 
> literature between Oligocene and Miocene.)

At least the Riversleigh cockatoo is early Miocene IIRC. The original 
description is doi:10.1111/j.1474-919X.1993.tb02804.x

> > too [few] cladistic studies with comprehensive
> sampling exist for reasons 
> > unknown
> 
> The reason is very simple: a morphological cladistic
> analysis of any kind of 
> decent size is at least a chapter of a PhD thesis.

Yes, but it's just as bad with molecular studies. Astuti has 2-3 nice ones 
(including the thesis), but apart from that it's just in-depth looks at 
particular clades, or very coarse general papers. The former is highly useful 
to me personally, but in the general scheme of things it's almost 
non-informative: the clades are usually Neotropical psittaciforms, which is 
about as far from base as one can get.

There is an _Agapornis_ or two (or something as similar to these as the 
Riversleigh fossil is to _Cacatua_) from Langebaanweg, a few Ma later than the 
cockatoo. This is highly valuable because it proves that the clade Mayr 
discusses was not only distinct ~20 mya, but that it had already radiated and 
dispersed. Its origin is in the general region of New Guinea as surely as this 
can be said in the absence of basal fossils. Oh, and the budgie is part of it 
too as it seems - it would thus have an interesting combination of 
plesiomorphic overall pattern and mildly apomorphic coloration among the crown 
Psittaciformes.

But the most interesting psittaciform probably still is the large species of 
Easter Island. A quadrate piece of a bird with a head size comparable to a 
kakapo. Nothing new on this since it was described nearly 15 years ago. 
Quaternary of course, but if anything even more tantalizing than _Mopsitta_. It 
might just about carry enough information to apply the results of the 
phylogenetic analyses to it, but I have not seen a photo of the wretched thing, 
and the description of the specimen was in a small-circulation journal. The 
Mascarenes taxa OTOH have recently been reviewed in Zootaxa and little 
questions remain.


Regards,

Eike 


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