BASAL PASSERIFORMS

["Matthew Troutman" <m_troutman@hotmail.com>]

I hope that the text of this message doesn't appear as small as my messages 
seem to be lately.  It is all hotmail's fault I can assure you.

<<<Well, if you really want to be paleo-politically correct,  I suppose that 
birds may be dinosaurs.>>>

<<If you want to be *SCIENTIFIC*, then we must regard birds as dinosaurs.  
On the other hand, if all you are interested in is a chat room for 
"dino-groupies", then go ahead and exclude Aves.>>

Hey, the "birdy-groupies" are taking offense! :-)

<<(Hey, a pigeon or sparrow prior to the K-T boundary (which would be 
different from a "pre-KT", or Jurassic and earlier, taxon... sorry, more 
nits to pick...) would be a MAJOR discovery!!).>>

According to many (if not most) recent neornithine phylogenies of Mindell et 
al., Sibley and Ahlquist, Woodbury, and Ericson, Passeriformes ("oscines" 
and "suboscines") may fall out to be very basal neognath birds, diverging in 
the late K or earlier.

Sibley and Ahlquist (1990) had passeriforms as basal to a large group of 
birds including columbiforms (doves), gruiforms (cranes, rails, bustards, 
kagu, possibly mesites and button-quails), and ciconiiforms (S&A's 
"Ciconiiformes" is different from most other classifications; this one 
includes classical falconiforms, pelecaniforms, and others).

Mindell (most recently Mindell et al., 1997) caused a big commotion at an 
AOU meeting when he presented his phylogeny of birds with passeriforms as 
VERY basal within neognaths.

Woodbury (1998) published results from his comparisons of the dorsal horn of 
most avian orders that suggests that passeriforms and columbiforms, along 
with other groups of "crown" neognaths, fall basal to a larger group of 
neognaths.  Also interesting is the fact that many avian orders are 
indicated to be polyphyletic in this study.

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?

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.

<<Focus on Mesozoic birds?  Not exclusively (I like my theropods with stumpy 
two-fingered arms!),>>

Oh, then you go for kiwis and penguins, huh? :-)

Matt Troutman
m_troutman@hotmail.com


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