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Bird analysis update!



You wouldn't have thought it would happen before my dissertation, would you? ;-) Anyway, I've added a few taxa and a few characters, and do hereby proclaim the following:

- I still have far too few characters -- 65, for 51 taxa.
- That is, for 50 taxa. Excluding the extremely fragmentary *Alexornis* helps... though not as much as I had hoped. The strict consensus is still near-perfect grass.
- The 50 % majority-rule consensus has a clade of (*Caudipteryx* (Scansoriopterygidae (*Microraptor*, *Archaeopteryx*, "basal Troodontidae", *Rahonavis*, *Shenzhouraptor*, *Jixiangornis*))). I thought the addition of *J.* would destroy this clade, which had occasionally cropped up earlier. I was very wrong.
- The sistergroup of this, which contains all unquestioned birds, likes to have *Sapeornis* at the base, followed by *Omnivoropteryx*.
- The following clades appear within Enantiornithes in the 50 % majority-rule consensus tree:


--+--*Soroavisaurus*
 `--+--*Avisaurus*
    `--*Vescornis*

--+--*Gobipteryx*
 `--+--*Liaoningornis*
    `--*Longirostravis*

and the following appears outside Ornithothoraces, often with *Yandangornis* and *Confuciusornis*:

--+--*Hulsanpes*
 `--+--*Lectavis*
    `--*Yungavolucris*

*L.* and *Y.* even appear in most or all attempts at a strict consensus (I forgot -- but it's all in the log file).

- *Jibeinia* sometimes occurs outside Ornithothoraces, sometimes it's the sister of *Otogornis* within Enantiornithes (...which doesn't exist in any strict consensus).
- *Protopteryx*, *Longipteryx*, *Eocathayornis* and, while I am at it, *Eoenantiornis* stay in Enantiornithes. I've seen them forming a Hennig comb within it, though (in this order). I'll try constraining them outside...
- *Iberomesornis* likes being the basalmost enantiornith, followed by *Noguerornis* (and later by the above).
- I wondered why (except for the toothless premaxilla) *Yandangornis* liked to cluster with *Confuciusornis*. It turned out that PAUP* said *Y.* reevolved its long tail ("more than 10 free caudal vertebrae"). I stopped that by making the character irreversible. Resolution of both consensus trees _decreased_!!! In addition, *Sapeornis* was said to have evolved its short tail (7 free caudals) independently of that of Pygostylia. The attraction of *Y.* to *Confuciusornis* is impressive. I conclude by begging that someone PLEASE translate the description of *Yandangornis* and/or publish decent pictures of it. It's clear that I need more characters, but at present I couldn't code any for *Y.*.
- Adding two easily codable characters from Julia Clarke's thesis finally stopped *Ichthyornis* clustering with Hesperornithes and made it switch to Neornithes (*Anas*). In the majority-rule consensus. Not in the strict consensus.


If anyone wants details, I'll go through the log file and send them tomorrow. (I can also send the Nexus file, of course.) Over here it's a quarter past 11 pm, and I'm tired, and my brother needs to rise early tomorrow... I'll also try excluding *Yandangornis* and some others, though especially in the case of *Y.* this is in principle a bad idea, because it's the only long-tailed bird that doesn't look like *Rahonavis* all over the skeleton. -- And I'll try reweighting. That always does interesting things.