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Re: New Jeholornis specimen



>  And good sternal information just as I'm coding that area. 
> I'm on character 180-the length/width ratio of the sternum. 
 
I fear this, and most other sternal characters, is so strongly related to 
ossification, and therefore ontogenetic and/or individual variation, that 
I've thrown the presence and shape of the lateral processes out of my 
little analysis which was once based on the matrix in chapter 11 of 
Mesozoic Birds (now 40 taxa, 50 characters, and growing). *Eoalulavis* 
looks a lot more ordinary now. :-) 
 
> > While *Shenzhouraptor* is said to have premaxillary teeth, right? 
> 
> No, Shenzhouraptor is said to lack visible dentition. 
 
False memory on my part. Great, this means that at present there's no 
evidence that *Jeholornis* is not a junior subjective synonym of 
*Shenzhouraptor*. :-) 
 
> Impossible to tell the condition in Jeholornis from the scapula in  
> lateral view, and the coracoid in anterior/ventral view. 
 
:-( 
 
> I also cannot determine  
> the condition in Otogornis, 
 
>From the photo and drawing in Mesozoic Birds it's not possible... I think 
it's somewhere in the archives that Kurochkin found it to have the 
euornithine condition. But so far I haven't been able to find similarities 
between it and *Ambiortus* (though I don't have a good pic of the latter 
either, let alone a description...); e. g. *A.* has a procoracoid process, 
*O.* does not... 
 
> Protopteryx has a flat articulation for the 
> coracoid on the scapula, so is intermediate between the enantiornithine 
> (and apparently basal) condition and the ornithuromorph one. 
 
Really? OK, a step matrix... 
While I am at it, I found out that it doesn't say anywhere what that of 
*Longipteryx* looks like. 
 
> > While I am at it, what should I choose as an outgroup for an analysis 
> > of the above problem, without having to make a 500-character 
> > coelurosaur analysis out of it? 
 
I should have mentioned what the ingroup is... Archie, *Rahonavis*, 
*Shenzhouraptor/Jeholornis*, *Hulsanpes*, *Yandangornis* (neither of the 
latter two is redundant) and Avebrevicauda (without most Ornithurae, 
*Nanantius*, and probably I'll have to throw *Alexornis* out because I 
can't find information about it; it appears to be very incomplete anyway). 
 
> Why not make a Denonychosauria outgroup by independently coding several  
> deinonychosaurs, then making PAUP treat them as a forcibly monophyletic  
> outgroup? 
 
Because they might be part of the ingroup in reality. After all, a few 
analyses (OK... one that I can think of, plus an outdated one of yours) 
have found Archie closer to dromies (with or without troodontids) than to 
birds, and my untested opinion goes in the same direction... analogously, 
it could be dangerous to take enigmosaurs or alvarezsaurs as the outgroup. 

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