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Re: BASAL PASSERIFORMS



>Ericson (at the Ostrom Symposium) was rumored to have have presented data 
>that supports a basal position of passeriforms among neognaths.  Was it a 
>sister-group relationship with galliforms, Ron?

Actually, as I recall this idea was only alluded to, not supported with
evidence (though it may have shown up in some of the projected cladograms -
not being equipped with the Palomar Telescope at the time, I was unable to
check all the details!)  All my notes say on the point (and it was
Ericson's talk) is that mtDNA evidence suggests that Passeriformes may be
the most basal neornithine lineage (an idea I find astonishing) and that
skeletal work with Ichthyornis groups Passeriformes and Galliformes as the
sister group to tinamous [!!!].  I would certainly like to see what
skeletal evidence Ericson was talking about....  I guess I'll have to wait
for the proceedings (unless this stuff is out somewhere else?).

>Given that we do know some neornithine groups from the late K, if 
>passeriforms are as basal as the above analyses (which I am not quite ready 
>to accept; passeriforms share many characters with piciforms and/or 
>bucerotiforms (Upupiformes)) then their fossil record would extend back at 
>least that far.

The fossil record of Passerines, in fact, does not even get back to the
K-T; they appear very late in the Northern Hemisphere (and may have
replaced an earlier no-passerine perching "guild" there containing birds
like the primobucconids), though there is an apparent Eocene(?) Southern
Hemisphere suboscine described by, if memory serves, Walter Boles of the
Australian Museum.  Sibley suggested that the Acanthisittids of New Zealand
may be the sister group of all other living Passeriformes; if (and I say
if!) they were on New Zealand when it broke away from West Antarctica
(which was pre-Eocene, right?) then Passerines may indeed be an older group
than fossils would indicate.
--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court                 
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@home.com