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Re: vultures and musophagids
<<<Anyway, in regards to Ron's statement that most workers think that
vulturids are derived ciconiids is not really true. Yes, Sibley and Alquist
have presented much molecular evidence and it is generally accepted that
vulturids are storks, but not everyone is willing to say so. Cracraft has
been rather cautious on this in his papers (unlike his grouping of owl in
falconiforms; other than vulturids in his phylogeny). Griffiths has
presented three syringeal characters (taken from a select group of birds)
that support a vulturid-falconiform clade (one of the characters is found in
an owl however). The debate is still open.>>>
<<From what I know about avian phylogeny, the question is whether New World
and Old World vultures are in fact related to one another in the first
place. Some authors exclude the latter from all other falconiforms and do
group them with the storks (there's a scavenging, vulture-like stork, the
marabou).>>
I should have made this a little more clear. Griffiths (1994; also included
is a refutation of S&A's DNA-DNA hybridization data, which is interesting)
argues that vulturids (the New World vultures), if they are nested in
Falconiformes, are the most basal members of the group because they lack
certain syringeal characters found in falconids and accipitrids (including
ospreys and secretary-birds, which do not differ greatly from classical
accipitrids in syringeal anatomy) and that Old World vultures are nested
with Acciptridae, which is really the old phylogeny. Griffiths evaluated
the studies of Rea and Ligon that supported the vulturid-stork clade and
found them to be based on plesiomorphic characters or ill-defined ones. I
don't yet buy it, but I think that the whole vulturid-falconiform-stork
thing is still an open question.
<<Then there's a suggestion that the maverick members of the Falconiformes
and Strigiformes, hawks (?) and barn owls respectively, share some
similarities, which might point to a divergence of Falconiformes from a
Strigiformes + Caprimulgiformes clade.>>
This is mainly Joel Cracraft's tree, which has been reproduced dozens of
times. However, Cracraft does not consider strigiforms to be nested close
to caprimulgiforms (why? Because "caprimulgiforms are leading toward a
swift design" (!)) and nests owls at the base of the falconiform tree a step
above vulturids. *Nobody* accepts this.
Matt Troutman
m_troutman@hotmail.com
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