Thomas Daniel B, Nascimbene Paul C, Dove Carla J, Grimaldi David A, James Helen F
1] Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA [2].
Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024-5192, USA.
Sci Rep. 2014 Jun 9;4:5226. doi: 10.1038/srep05226.
Plumage colours bestowed by carotenoid pigments can be important for visual communication and likely have a long evolutionary history within Aves. Discovering plumage carotenoids in fossil feathers could provide insight into the ecology of ancient birds and non-avian dinosaurs. With reference to a modern feather, we sought chemical evidence of carotenoids in six feathers preserved in amber (Miocene to mid-Cretaceous) and in a feather preserved as a compression fossil (Eocene). Evidence of melanin pigmentation and microstructure preservation was evaluated with scanning electron and light microscopies. We observed fine microstructural details including evidence for melanin pigmentation in the amber and compression fossils, but Raman spectral bands did not confirm the presence of carotenoids in them. Carotenoids may have been originally absent from these feathers or the pigments may have degraded during burial; the preservation of microstructure may suggest the former. Significantly, we show that carotenoid plumage pigments can be detected without sample destruction through an amber matrix using confocal Raman spectroscopy.
由类胡萝卜素色素赋予的羽毛颜色对于视觉交流可能很重要，并且在鸟类中可能有着悠久的进化历史。在化石羽毛中发现羽毛类胡萝卜素可以深入了解古代鸟类和非鸟类恐龙的生态。参照一根现代羽毛，我们在保存在琥珀中的六根羽毛（中新世至白垩纪中期）以及保存在压缩化石中的一根羽毛（始新世）中寻找类胡萝卜素的化学证据。通过扫描电子显微镜和光学显微镜评估了黑色素沉着和微观结构保存的证据。我们观察到了精细的微观结构细节，包括琥珀和压缩化石中黑色素沉着的证据，但拉曼光谱带并未证实其中存在类胡萝卜素。这些羽毛最初可能就不存在类胡萝卜素，或者这些色素在埋藏过程中可能已经降解；微观结构的保存可能表明是前者。重要的是，我们表明，可以使用共聚焦拉曼光谱通过琥珀基质在不破坏样品的情况下检测类胡萝卜素羽毛色素。
