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Re: Yay! Cladobabble! :-)



----- Original Message -----
From: "Nick Gardner" <ratites637@hotmail.com>

> David, is there something in particular you are aiming for? In phylogenies
> that have been proposed by GSP (1988, 2002) and CMIIW, yourself, these
taxa
> were considered more derived than Archaeopteryx.  If this is the case,
then
> Archaeopteryx is not a member of Aves.

:-) Exactly. I'd rather risk that Archie is not a bird than that
*Tyrannosaurus* or *Therizinosaurus* are ones. But I could live with the
latter situation...

> Of course, GSP (1988) states:  "As
> for myself, since most theropods are usually excluded from Aves, I feel it
> is all right to exclude protobirds too, even a flying one like
> Archaeopteryx, and I prefer to restrict Aves to true birds, including the
> toothy ones.

To me, it appears that, starting from something like Archie, flight was
improved 2 or 3 times independently: in the lineage leading towards dromies
(such as *Microraptor* and maybe *Sinornithosaurus*, you know, flange on
phalanx II-1...), the lineage leading towards *Rahonavis* and
*Shenzhouraptor* (same flange, joint between scapula and coracoid...), and
in the lineage leading towards Avebrevicauda. And I feel only the latter
should be called birds = Aves.
        (Especially after reweighting, my analysis supports a clade of
(Archie, Scansoriopterygidae (basal Troodontidae (*Microraptor*
(*Rahonavis*, *Shenzhouraptor*)))) -- when *Hulsanpes* is excluded from the
analysis. Otherwise, Pygostylia + *Sapeornis* + *Yandangornis* is not the
sistergroup to all of the above, but only to *R.* + *S.*. I haven't tried
yet if *Jixiangornis* is capable of messing this up. If someone with more
time than I would like my NEXUS file... :-) And then of course my analysis
isn't a coelurosaur analysis. Therefore, maybe, troodontids are completely
out of place. I can't find that out. -- Oh, before I forget, most of the
codings for Scansoriopterygidae are 0. Which means that in any case I need
more characters.)

> Also, why do you include Scansoriopteryx heilmanni as a taxon that should
be
> excluded from Aves?

Because I feel that something like an aye-aye doesn't look like a bird. On
the other hand, it may well have been able to fly, so something that looks
like a bird with a ludicrously long 3rd finger still looks like a bird...
was just a suggestion. January 1, 200n is still far away... :-)

> I find PhyloCode to be interesting, however, I have a few problems.
> Currently, I would like to know why they want all proper taxa to be
> italicized, as opposed to only species, and I suppose the "arbitrary"
genus
> as well.

When you can't tell what a genus is, you might just as well italicize all
taxon names. They look more official this way, more distinguishable in a
text (capital letters aren't enough; as an extreme example, in German all
nouns are capitalized). So... why not? :-)