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Re: New Zealand's Giant Eagle Showed Rapid Size Gain

On 12/1/05 7:33 am, "a23813@ualg.pt" <a23813@ualg.pt> wrote:

> Quoting Tim Williams <twilliams_alpha@hotmail.com>:
>> Christopher Taylor wrote:
>> _Aptornis_ is deeply weird for other reasons.  Like many large
>> island-dwelling birds, the adzebill has proven difficult to pin down
>> phylogenetically.  Livezey (1998) put it in the Gruiformes, close to the
>> kagu (_Rhynochetos_) [...]
> It may be more a case of convergence but I couldn't help notice the outward
> similarity between the weka* and the illustrations of the Adzebill**.
> I think it would be more reasonable to assume that _Aptornis_ would be a giant
> rail related to _Gallirallus_ but then again this is just some educated
> guessing based on my knowledge.
> Just my two cents,
> Renato Santos

Actually, Houde et al. (1997) did find _Aptornis_ to be the sister group to
Rallidae, with _Psophia_ sister to both, in an analysis of mtDNA.
_Rhynochetos_ and _Eurypyga_ were a much more distant clade.
    However, both Houde et al.'s and Livezey's analyses may have suffered
from missing data, probably due to the difficulties of extracting ancient
DNA in the former, and the extreme apomorphy of _Aptornis_ in the latter
(both arguments also applicable to _Rhynochetos_ - DNA was probably
extracted from a museum specimen, and _Rhynochetos_ is, like _Aptornis_, a
large, flightless bird, so convergence is a distinct possibility). Looking
at the skull, I don't think at a glance that _Aptornis_ does look much like
_Gallirallus_, but nor does it look much like anything else (except that,
having recently rewatched 'The Dark Crystal', I'm struck by a remarkable
resemblance to a Skeksi :-) ).
    Offhand, when _Aptornis otidiformis_ was first described by Owen in
1844, he actually regarded it as a moa (_Dinornis otidiformis_). The
spelling _Apterornis_ has appeared in some places - it was actually used by
Owen in a paper that appeared in print in 1848 a whole nine days (:-P)
before the paper in which he called it _Aptornis_ (the name he invariably
used subsequently). As it was used almost exclusively since until fairly
recent attempts to reinstate _Apterornis_, the ICZN declared _Aptornis_ the
official conserved spelling in 1997. To cap it all off, Worthy & Holdaway
(2002) recently found that a paper by Mantell (Mantell the describer of
_Iguanodon_, that is) which referred to _Aptornis_ by name actually appeared
in print two months and eleven days before the _Apterornis_ paper. So
_Aptornis_ is the correct spelling, but perhaps with Mantell, not Owen, as
the author.
    Confused yet? ;-)


        Christopher Taylor