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Sinosauropteryx feather paper (free pdf)
From: Ben Creisler
bscreisler@yahoo.com
A new paper--the pdf is free for now.
Theagarten Lingham-Soliar ("2011")
The evolution of the feather: Sinosauropteryx, life, death and preservation of
an alleged feathered dinosaur.
Journal of Ornithology (advance online publication)
DOI: 10.1007/s10336-011-0787-x
http://www.springerlink.com/content/0383285508u76214/
free pdf: http://www.springerlink.com/content/0383285508u76214/fulltext.pdf
Among the spectacular dinosaur fossils reported from the Jehol Group of
northeastern China is the most celebrated, Sinosauropteryx, which continues to
excite interest in questions concerning feather origins--most recently with
alleged identifications of melanosomes and colour in its integumental
structures, which proved unfounded. The crucial significance of Sinosauropteryx
is undoubtedly the focus on its basal theropod status and potentially pivotal
position in informing models of the early evolutionary origin of modern
feathers. On the basis of new evidence in Sinosauropteryx NIGP 127587 and GMV
2124, it is shown here that the alleged protofeathers were not free filaments
but part of a composite tissue. It is shown that the tail terminates in a
unique, smoothly edged, spatula-shaped structure. The dinosaurs died in the
vicinity of a lake. For the first time, the taphonomy of Sinosauropteryx is
investigated on the basis of aboveground decomposition
experiments on living animals so as to get a better understanding of
conditions preceding the death of the animal, its death, decomposition and
finally preservation of soft tissue as manifested in the fossil. The signs
point strongly to invertebrate colonization of the carcass of Sinosauropteryx
rather than vertebrate predation or scavenging, with moderate decay associated
with the purge fluids while major decay was forestalled by burial, at most a
few days after death. Lastly, a theory that the opisthotonic posture of fossils
such as Sinosauropteryx NIGP 127587 occurred perimortem as a consequence of
neural spasms provides the basis for a forensic reconstruction of the stages
leading to the dinosaur’s death and the final preserved position of the
external, dorsally preserved soft tissue, which proves to be more consistent
with a uniform crest than individual, free protofeathers.