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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.