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