Science 9 March 2012:
Vol. 335 no. 6073 pp. 1215-1219
DOI: 10.1126/science.1213780

Report

Reconstruction of Microraptor and the Evolution of Iridescent Plumage

1.     Quanguo Li¹,

2.     Ke-Qin Gao²,

3.     Qingjin Meng¹,

4.     Julia A. Clarke³,

5.     Matthew D. Shawkey^4,*,

6.     Liliana D’Alba⁴,

7.     Rui Pei⁵,

8.     Mick Ellison⁵,

9.     Mark A. Norell⁵,

10.  Jakob Vinther^3,6

To whom correspondence should be addressed. E-mail: shawkey@uakron.edu

Iridescent feather colors involved in displays of many extant birds are produced by nanoscale arrays of melanin-containing organelles (melanosomes). Data relevant to the evolution of these colors and the properties of melanosomes involved in their generation have been limited. A data set sampling variables of extant avian melanosomes reveals that those forming most iridescent arrays are distinctly narrow. Quantitative comparison of these data with melanosome imprints densely sampled from a previously unknown specimen of the Early Cretaceous feathered Microraptor predicts that its plumage was predominantly iridescent. The capacity for simple iridescent arrays is thus minimally inferred in paravian dinosaurs. This finding and estimation of Microraptor feathering consistent with an ornamental function for the tail suggest a centrality for signaling in early evolution of plumage and feather color.

       Received for publication 9 September 2011.

       Accepted for publication 9 February 2012.

       Acknowledgments: The research was funded by NSF EAR 0938199, Air Force Office of Scientific Research FA9550-09-1-0159, National Natural Science Foundation of China 40532008, Beijing Municipal Bureau of Human Resources, Beijing Academy of Science and Technology (BJAST) Innovation Team Fund, University of Texas at Austin, and the American Museum of Natural History. The Copenhagen Museum of Natural History (J. Fjeldsaa) and the Yale University Peabody Museum (R. O. Prum and K. Zyskowski) provided extant feather samples. The fossil specimen is accessioned to the Beijing Museum of Natural History (BMNHC).

       Data are presented in the supporting online material.

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