Two papers were published early last year that described colour in fossil feathers. One in Nature, and one in Science. These studies were based on a brilliant deduction by Jacob Vinther, who realised that colour structures seen in modern feathers may be preserved in fossils. This work was later applied to a newly described fossil penguin, with curious results. The colour structures identified by Vinther are associated with trace elements, which can also be used to reconstruct colour patterning in fossil feathers. Roy Wogelius and colleagues recently mapped the surface of a Late Cretaceous bird fossil, using x-ray fluorescence, allowing them to reconstruct provide even more insight into fossil colour patterns. The Royal Society of Chemistry have provided an excellent summary of the article.
Wogelius RA, Manning PL, Barden HE, Edwards NP, Webb SM, Sellers WI, Taylor KG, Larson PL, Dodson P, You H, Da-qing L and Bergmann U. 2011. Trace Metals as Biomarkers for Eumelanin Pigment in the Fossil Record. Science DOI: 10.1126/science.1205748
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