Re: How are columbiformes (doves and pigeons) related to psittaciformes?

["Mickey Mortimer" <Mickey_Mortimer111@msn.com>]

John Pourtless wrote-

> I would quite agree that assigning an isolated and rather fragmentary
lower
> jaw to crown orders is not particularly merited.  Problems are after all
> legion in using fragmentary material to identify Cretaceous or even
Tertiary
> birds, which has been noted before (e.g., Olson 1985a) and marvelously
> demonstrated by the example of *Limnofregata azygosternon* (Olson 1977b).

That's science for you.  If we waited until we were sure of something before
hypothesizing it, nothing would be known.  Regarding Limnofregata, you're
referring to its recent reidentification as a sulid (Gulas-Wroblewski,
2003), right?

> As for the whole issue of pigeon/dove relationships...I find the papers
> cited by several of you most interesting to be sure, but am still cautious
> on the matter and would agree with Sibley & Ahlquist (1990) in stating
only
> that Columbiformes have no close living relatives, and that sandgrouse are
> not closely related thereto.

Sounds like a cop-out to me.  Something has to be their closest living
relative, regardless of how quantitatively close it is.  Pteroclids
(sandgrouse) were found to be their sister group in both recent large scale
phylogenetic analyses of neornithine orders, which looks like pretty good
evidence to me.  Mayr and Clarke (2003) found the relationship supported by
seven synapomorphies-
- Os ectethmoidale, greatly expanded and more or less inflated, plate-like,
with dorsal margin largely fused
with os frontale.
- Vomers vestigial or absent.
-  Several thoracic vertebrae fused to a notarium.
- Humerus short and stocky with crista deltopectoralis strongly protruding
and triangular.
- Humerus, tuberculum dorsale greatly elongated proximodistally.
- Femur, crista trochanteris markedly projected cranially.
- Musculus flexor perforans et perforatus digiti III, vinculum.

Mickey Mortimer