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RE: Sinosauropteryx tail "scales"

I have now received the TLS paper on *Sinosauropteryx prima* preservation. I 
did not realize that the other paper I mentioned was freely available online, 
and greatly appreciate being sent it nonetheless!


  Jaime A. Headden
  The Bite Stuff (site v2)

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

"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 

> Date: Thu, 14 Mar 2013 12:07:38 -0700
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Sinosauropteryx tail "scales"
> From: Ben Creisler
> bcreisler@gmail.com
> Checking the DML archives, it appears this paper did not get mentioned
> when it appeared in pre-publication form (my bad, I guess). It's
> officially published now.
> Theagarten Lingham-Soliar (2013)
> The evolution of the feather: scales on the tail of Sinosauropteryx
> and an interpretation of the dinosaur’s opisthotonic posture.
> Journal of Ornithology 154 (2): 455-463
> DOI: 10.1007/s10336-012-0910-7
> http://link.springer.com/article/10.1007/s10336-012-0910-7
> The epidermis and dermis are exposed in the tail region of the
> theropod dinosaur Sinosauropteryx. The specimen under study, like many
> others of the genus and other air-breathing vertebrates discovered in
> the Jehol biota, shows strong opisthotonus (i.e., recurvature of the
> spine) that includes the neck and tail. Here, recurvature of the tail
> upwards is considered to have aided the separation of the dermal and
> epidermal elements of the skin. Addressing a somewhat controversial
> question, the sequence of events in which this apparently occurred
> also suggests that the development of opisthotonus may have occurred
> post mortem rather than perimortem in this specimen. Crucially,
> epidermal structures considered to be scales are preserved overlying
> the posterior part of the tail and alongside it. They are
> approximately 2.0–2.5 mm in diameter and have distinctive papillae
> radiating around a central point, comparable to scales in some modern
> day lizards. Some of these scales overlie thick structural fibres
> external to the body outline, extending posteriorly at steep angles to
> the body's long axis, considered by many workers to be protofeathers.
> Intervening between the epidermal scales and the deeper structural
> fibres are preserved traces of a dermal fibre meshwork with two layers
> of oppositely oriented fibres.