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AW: The cladogram from the supp. inf. of the *Anchiornis* paper




--- David Marjanovic <david.marjanovic@gmx.at> schrieb am So, 11.10.2009:

> Avialae
>  |--+--*Epidendrosaurus*
>  |  `--*Epidexipteryx*
>  `--+--+--*Archaeopteryx*
>     |  `--*Wellnhoferia*

As expected. Not helpful though.

>     `--+--*Jeholornis*
>        `--+--*Sapeornis*
>           `--+--*Confuciusornis*
>              `

"Nice comb" too...

I'd advise anyone interested in the topology here to include at least 3 
Enantiornithes and another taxon of Confuciusornithidae that is not adult _C. 
sanctus_. (As per "_Wellnhoferia_")

> antirrhopus* and *Troodon formosus*". Aves is defined right
> below as "the least inclusive clade including
> *Archaeopteryx* and Neornithes".

Including Archie in *anything* is asking for trouble. Not before we know waht's 
with Guimarota, and not before we know more about theropod diversity on the W 
shore of the Turgai Sea from shortly before Archie to 20 Ma later. (Even if no 
theropods are found - *anything* about the ecosystem there will help).

> I still don't believe in *Wellnhoferia*. :-)

The current bones paper and a few allometry friends of it have strangled it in 
its sleep. This is just its ghost walking.

> *Epidendrosaurus* probably includes *Scansoriopteryx*, and
> *Jeholornis* *Shenzhouraptor*.
> 
> I wonder how much this topology can be trusted, because
> among the autapomorphies of Avialae that *Anchiornis* lacks
> is "reversed hallux". Ehem.

Ehem indeed. Did they code it as reversed in Archie? If so, oh boy...

(It should be thrown out. Rather, use 4-5 characters of the hallux' 
articulation with the metatarsus (if you can find as many. But 2 should be 
possible, and even 2 ought to be better).)

It's nice to include _Shenzhouraptor_, but you need more of this sort of 
fossils. 2 Sapeornithidae too (they barely could have, but data availability 
has much improved since they did the study).


> Dromaeosauridae
>  |--+--*Rahonavis*
>  |  `--+--*Unenlagia*
>  |     `--*Buitreraptor*


> But at least *Rahonavis* is here to stay, 4 to 6 nodes away
> from *Anchiornis*, *Archaeopteryx* and *Jeholornis*.

Which is highly satisfying. But it also has a very long ghost lineage. 
Altogether the situation is clearer here though: it seems that the original 
unenlagiine was one of those maniraptoran lineages that were "almost-birds", 
and became less volant (not that it ever *needs* to have been able to lift off 
except accidentially in a gale - and I would rather tend to "no, never" ATM) in 
the main lineage and more volant (though only to about Archie level) in the 
lineage apparently endemic on the splinter off SE Africa.

So... where are the (southern) African unenlagiine almost-birds? Did they 
evolve towards or away from flight? (I'd presume the latter; islands seem to 
help in becoming volant).

What is known about unenlagiine habitat in South America? Was there grassland 
already? How dense were the woods, if any, approximately, in internal density 
and as proportion of the landscape?


Regards,

Eike