naa a22 4500 510808808 CHVBK 20180411083431.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1007/s12542-013-0173-5 doi (NATIONALLICENCE)springer-10.1007/s12542-013-0173-5 Exceptional three-dimensional preservation and coloration of an originally iridescent fossil feather from the Middle Eocene Messel Oil Shale [Elektronische Daten] [Natasha Vitek, Jakob Vinther, James Schiffbauer, Derek Briggs, Richard Prum] A feather from the Eocene Messel Formation, Germany, has been demonstrated to have been originally structurally colored by densely packed sheets of melanosomes similar to modern iridescent feathers exhibiting thin-film diffraction. The fossil itself currently exhibits a silvery sheen, but the mechanism for generating this optical effect was not fully understood. Here we use scanning electron microscopy, electron probe microanalysis, and dual-beam focused ion beam scanning electron microscopy to investigate the source of the silvery sheen that occurs in the apical feather barbules. Focused ion beam scanning electron microscopy provides a powerful tool for studying three-dimensionality of nanostructures in fossils. Use of the method reveals that the flattened apical barbules are preserved almost perfectly, including smooth structural melanosome sheets on the obverse surface of the fossil feather that are identical to those that cause iridescence in modern bird feathers. Most of each apical barbule is preserved beneath a thin layer of sediment. The silvery sheen is generated by incoherent light diffraction between this sediment layer and melanosomes and, although related to the original iridescence of the feather, is not a feature of the feather itself. The reddish and greenish hues frequently exhibited by fossil feathers from the Messel Formation appear to be due to precipitates on the surface of individual melanosomes. Springer-Verlag Berlin Heidelberg, 2013 Exceptional preservation nationallicence Color nationallicence Melanin nationallicence Iridescence nationallicence Fossil bird nationallicence Außergewöhnliche Erhaltung nationallicence Farberhaltung nationallicence Melanin nationallicence Iridisieren nationallicence Fossile Vögel nationallicence Vitek Natasha Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut Vinther Jakob Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut Schiffbauer James Department of Geological Sciences, University of Missouri, 65211, Columbia, MO, USA aut Briggs Derek Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut Prum Richard Peabody Museum of Natural History, Yale University, 170 Whitney Avenue, 06511, New Haven, CT, USA aut Paläontologische Zeitschrift Springer Berlin Heidelberg 87/4(2013-12-01), 493-503 0031-0220 87:4<493 2013 87 12542 https://doi.org/10.1007/s12542-013-0173-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12542-013-0173-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vitek Natasha Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut NATIONALLICENCE 700 1- Vinther Jakob Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut NATIONALLICENCE 700 1- Schiffbauer James Department of Geological Sciences, University of Missouri, 65211, Columbia, MO, USA aut NATIONALLICENCE 700 1- Briggs Derek Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, 06520, New Haven, CT, USA aut NATIONALLICENCE 700 1- Prum Richard Peabody Museum of Natural History, Yale University, 170 Whitney Avenue, 06511, New Haven, CT, USA aut NATIONALLICENCE 773 0- Paläontologische Zeitschrift Springer Berlin Heidelberg 87/4(2013-12-01), 493-503 0031-0220 87:4<493 2013 87 12542 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer