NEORNITHINE PHYLOGENY vs pterosaurs

[darren.naish@port.ac.uk]

On the neornithine phylogeny that appears on the tree of life  
pages, David Peters wrote...

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According to the web page author: "Ordinal phylogenies 
based on morphological characters have many polytomies 
deep within them because few derived morphological 
characters have been recognized that unite particular avian 
orders in sister group relationships."

The cladogram of the neornithes appeared to be one giant 
polytomy. If someone has information other than the above 
and it has appeared on the list, forgive me, my "blinders" 
were on. Please send updates on or off-line.
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The cladogram David's talking about is at..
http://tolweb.org/tree?group=Neornithes&contgroup=Aves

The cladogram on that site is mostly based on Cracraft 
(1988) with some of the groupings following those 
suggested by Sibley & Ahlquist (1990) and Mindell et al. 
(1997). Some of the relationships shown there are unlikely: 
Galloanseres (galliforms + anseriforms) for example is 
almost certainly the sister-taxon to the other neognaths, and 
not to the palaeognaths as shown. The problem is that 
hardly any work has been done on the 'total phylogeny' of 
neornithines, mostly because few people have enough 
research time to devote the required resources to a project 
that big. However, a neornithine supertree is under way and 
preliminary results have been published since that website 
was put on-line. See.. 

Livezey, B. C. & Zusi, R. L. 2001. Higher-order 
phylogenetics of modern Aves based on comparative 
anatomy. _Netherlands Journal of Zoology_ 51, 179-205.

I understand Mayr et al. have also just published their long-
awaited 'Monophyletic groups within "higher land birds" - 
comparison of morphological and molecular data' in 
_Journal of Zoological Systematics and Evolutionary 
Research_. I haven't seen this yet.

A large number of recent papers in the ornithological 
literature have also added complexity to the branching 
pattern in the neornithine cladogram. A 'consensus' 
cladogram incorporating the results of all these newer 
studies would certainly be bushier than the rather skeletal 
tree shown on the site: e.g., Mayr (2003a) showed that 
strigiforms, apodiforms, caprimulgiforms s.l. and 
trogoniforms probably all form a clade as do coliiforms, 
coraciiforms s.s., alcediniforms and upupiforms; Mayr 
(2003b) showed that ciconiiforms s.s., procellariforms and 
pelecaniforms form a clade. 

Search the DML archives if you want more info on these 
studies.

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So, are the passerines basal to other forms? And would their 
loss create a visible gap? Apparently, at this time, no one 
can say.
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Suggestions that passerines might be basal neognaths have 
been refuted and are apparently artefacts resulting from 
long-branch attraction. Most workers and most studies 
strongly indicate that passerines are members of the 'higher 
landbird' assemblage and thus close to coraciiforms s.l., 
piciforms s.l., cuculiforms and so on. They are indeed 
highly derived neornithines and thus one of the last groups 
to appear. 

-- 
Darren Naish
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL

email: darren.naish@port.ac.uk
tel: 023 92846045