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Re: [...] Archaeopteryx 10



----- Original Message -----
From: "evelyn sobielski" <koreke77@yahoo.de>
Sent: Sunday, January 28, 2007 1:04 AM
Subject: RE: Livezey and Zusi's big bird morph analysis and Archaeopteryx 10

Mayr, Pohl, Hartman and Peters, 2007. The tenth
skeletal specimen of
Archaeopteryx. Zoological Journal of the Linnean
Society. 149 (1), 97 -- 116.

An interesting outcome of this study is the distinction of two species: *A. lithographica*, including the London (1), Maxberg (3), Haarlem (4), and Solnhofen (5) specimens, and *A. siemensii*, including the Berlin (2), Munich (7), and Thermopolis (10) specimens. *Wellnhoferia grandis* is sunk because, while distinct from *A. siemensii*, it cannot be told apart from *A. lithographica*, and *A. bavarica* is sunk because the supposed sternum is part of the coracoid, removing the main difference between it and *A. siemensii* -- various proportions differ between the Munich specimen and the Berlin specimen, but in these the Thermopolis specimen is intermediate. The very small Eichstätt specimen (6), the very incomplete 8th specimen, and the inaccessible 9th specimen are not assigned to a species. -- *A. lithographica* is larger, has much larger flexor tubercles on the toe claws, different limb proportions, a stouter metatarsus, and a constriction in the middle of the premaxillary tooth crowns; the other features previously considered diagnostic for *Wellnhoferia* could also be diagnostic for *A. lithographica*, but are not preserved in the other three specimens; the end of the tail is not preserved in the Solnhofen specimen, so its tail length, previously considered diagnostic, can only be estimated.


The first toe is said to point medially (apparently as in *Confuciusornis*) rather than cranially.

Bonus points for putting the dot on Elzanowski's z!

Does it contain a phylogenetic analysis with more taxa
than the preliminary study ("A well-preserved...
theropod features") - on both sides of Archie?

No, it doesn't contain any phylogenetic analysis at all. Apparently no new features were discovered since the original 2005 paper.


I'm most eagerly awaiting that. Their
placement of Confuciusornis in the Microraptor clade
is possibly as large a revolution

I think you weren't onlist yet when Mickey M showed the result was due to typos such as coding the tooth attachment of *Rahonavis* for which no head or neck is known... I'll dig up the links in a few hours. That's not to say such a result couldn't come out in the next analysis, but it does not in this one.


For another
thing, it would indicate Gauthier's, not Sereno's
definition of Aves is more meaningful;

Hardly. I do think, though, it's a good argument for me to finally publish my proposed definition!


and that
(gasp!) Archie might be excluded from the Aves
altogether at some future date...

Excluding Archie is not the same as including everything from *Sapeornis* to *Ichthyornis*. My definition makes the former possible (depending on the phylogeny) but avoids the latter (unless Kurochkin is right -- fat chance --; in that case "Saururae" would drop out).


"Bird", if the Mayr et al
study is worth anything, is a form taxon with no
phylogenetic merit if one includes the fossil record,

You're way too pessimistic :-)

The message from the preliminary analysis of Archie
#10 is that either Confuciusornis or Archie were Aves -
and in fact, maybe neither! -, but not both

I don't see anything that could pull *Confuciusornis* out of its position within Avebrevicauda.


We need more analyses

Here I agree.

PS: Is the character set and matrix for Livezey/Zusi
available separately?

Yes, as cited, for 25 $.