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Beipiaosaurus and Feather Homology

Notice arrived in my mail today of a new paper (in press), of a new specimen of 
*Beipiaosaurus inexpectatus* involving a nearly complete skeleton anterior to 
the pelvis, including a complete skull, forelimbs, and vertebrae, all in 
articulation. This is not the big news. The material involves what were already 
noteworthy preserved "feather" homologs, filamentous material "dubiously" 
associated in a clearly defining halo around the body. Instead of forming a 
fuzzy rim, the filaments are thick and project clearly from the edge of the 
bone outward, and are reminiscent of nothing other than the "bristles" of the 
*Psittacosaurus* specimen described by Mayr et al.


Xu x., Zheng X.-t. & You H.-l. (in press) A new feather type in a nonavian
  theropod and the early evolution of feathers. _Proceedings of the
  National Academy of Sciences (Philadelphia)_. doi: 10.1073/pnas.0810055106


  "All described feathers in nonavian theropods are composite structures
   formed by multiple filaments. They closely resemble relatively advanced
   stages predicted by developmental models of the origin of feathers, but
   not the earliest stage. Here, we report a feather type in two specimens
   of the basal therizinosaur *Beipiaosaurus*, in which each individual
   feather is represented by a single broad filament. This morphotype is
   congruent with the stage I morphology predicted by developmental
   models, and all major predicted morphotypes have now been documented in
   the fossil record. This congruence between the full range of
   paleontological and developmental data strongly supports the hypothesis
   that feathers evolved and initially diversified in nonavian theropods
   before the origin of birds and the evolution of flight."

  I would like to hear what Theagarten Lingham-Soliar's opinion on this 
material is.


Jaime A. Headden

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)