Genesis of the New Papers

[Tim Williams <twilliams_alpha@hotmail.com>]

Barrett, P.M., Upchurch, P., Zhou, X.-D., and Wang, X.-L. (2007).  The skull 
of _Yunnanosaurus huangi_ Young, 1942 (Dinosauria: Prosauropoda) from the 
Lower Lufeng Formation (Lower Jurassic) of Yunnan, China.  Zool. J. Linn. 
Soc. 150: 319-341.

Abstract: "The Lower Lufeng Formation (Lower Jurassic: 
?Hettangian??Sinemurian) of Yunnan Province, China, has yielded an important 
and diverse fauna of terrestrial vertebrates that is dominated by early 
sauropodomorph dinosaurs (prosauropods and basal sauropods).  Nevertheless, 
few of these animals have been studied in detail, undermining their 
potential significance in understanding sauropodomorph phylogeny, 
palaeobiology, and palaeoecology.  Here, we present a detailed 
re-description of the cranial osteology of _Yunnanosaurus huangi_ Young, 
1942 and propose an emended diagnosis for this taxon on the basis of 
numerous autapomorphic characters (including an expanded internarial bar, 
unusual midline cranial bosses, and the possession of elongate maxillary 
tooth crowns lacking marginal serrations).  Incorporation of these novel 
anatomical data into existing phylogenetic analyses of sauropodomorph 
interrelationships substantially affects the resolution, length, and 
topologies of the trees recovered.  Although the phylogenetic position of 
_Yunnanosaurus_ remains labile, these new analyses undermine previous 
suggestions that the former was the sister taxon of the southern African 
prosauropod _Massospondylus_.  Several features of the skull of 
_Yunnanosaurus_ (small external nares, cranial bosses, tooth crown 
morphology, and the lack of maxillary foramina) indicate that the 
palaeobiology of _Yunnanosaurus_ may have been rather different from that of 
other prosauropods and basal sauropods, although more detailed functional 
studies and better material are needed to confirm this suggestion."

_________________________________________________________________
Get a preview of Live Earth, the hottest event this summer - only on MSN 
http://liveearth.msn.com?source=msntaglineliveearthhm